02254nas a2200217 4500008004100000245009400041210006900135260001200204300000600216490000700222520158800229653002601817653002401843653001901867653002401886653001801910100002301928700002101951700002201972856004201994 2025 eng d00aRethinking the lake history of Taylor Valley, Antarctica during the Ross Sea I glaciation0 aRethinking the lake history of Taylor Valley Antarctica during t c01/2025 a90 v153 a

The Ross Sea I glaciation, marked by the northward advance of the Ross Ice Sheet (RIS) in the Ross Sea, east Antarctica, corresponds with the last major expansion of the West Antarctic Ice Sheet during the last glacial period. During its advance, the RIS was grounded along the southern Victoria Land coast, completely blocking the mouths of several of the McMurdo Dry Valleys (MDVs). Several authors have proposed that very large paleolakes, proglacial to the RIS, existed in many of the MDVs. Studies of these large paleolakes have been key in the interpretation of the regional landscape, climate, hydrology, and glacier and ice sheet movements. By far the most studied of these large paleolakes is Glacial Lake Washburn (GLW) in Taylor Valley. Here, we present a comprehensive review of literature related to GLW, focusing on the waters supplying the paleolake, signatures of the paleolake itself, and signatures of past glacial movements that controlled the spatial extent of GLW. We find that while a valley-wide proglacial lake likely did exist in Taylor Valley during the early stages of the Ross Sea I glaciation, during later stages two isolated lakes occupied the eastern and western sections of the valley, confined by an expansion of local alpine glaciers. Lake levels above ~140 m asl were confined to western Taylor Valley, and major lake level changes were likely driven by RIS movements, with climate variables playing a more minor role. These results may have major implications for our understanding of the MDVs and the RIS during the Ross Sea I glaciation.

10aGlacial Lake Washburn10aMcMurdo Dry Valleys10aRoss Ice Sheet10aRoss Sea glaciation10aTaylor Valley1 aStone, Michael, S.1 aDoran, Peter, T.1 aMyers, Krista, F. uhttps://www.mdpi.com/2076-3263/15/1/902587nas a2200313 4500008004100000022001400041245012700055210006900182260001200251300001100263520145800274653001701732653001401749653000801763653001901771653001501790100002301805700001801828700001501846700002401861700002501885700003301910700002901943700001701972700002201989700002102011700002102032856022002053 2024 eng d a0954-102000aMcMurdo Dry Valley lake edge ‘moats’: The ecological intersection between terrestrial and aquatic polar desert habitat0 aMcMurdo Dry Valley lake edge moats The ecological intersection b c04/2024 a1 - 173 a

Aquatic ecosystems - lakes, ponds and streams - are hotspots of biodiversity in the cold and arid environment of Continental Antarctica. Environmental change is expected to increasingly alter Antarctic aquatic ecosystems and modify the physical characteristics and interactions within the habitats that they support. Here, we describe physical and biological features of the peripheral ‘moat’ of a closed-basin Antarctic lake. These moats mediate connectivity amongst streams, lake and soils. We highlight the cyclical moat transition from a frozen winter state to an active open-water summer system, through refreeze as winter returns. Summer melting begins at the lakebed, initially creating an ice-constrained lens of liquid water in November, which swiftly progresses upwards, creating open water in December. Conversely, freezing progresses slowly from the water surface downwards, with water at 1 m bottom depth remaining liquid until May. Moats support productive, diverse benthic communities that are taxonomically distinct from those under the adjacent permanent lake ice. We show how ion ratios suggest that summer exchange occurs amongst moats, streams, soils and sub-ice lake water, perhaps facilitated by within-moat density-driven convection. Moats occupy a small but dynamic area of lake habitat, are disproportionately affected by recent lake-level rises and may thus be particularly vulnerable to hydrological change.

10aconnectivity10aecosystem10aice10amicrobial mats10atransition1 aStone, Michael, S.1 aDevlin, Shawn1 aHawes, Ian1 aWelch, Kathleen, A.1 aGooseff, Michael, N.1 aTakacs-Vesbach, Cristina, D.1 aMorgan-Kiss, Rachael, M.1 aAdams, Byron1 aBarrett, John, E.1 aPriscu, John, C.1 aDoran, Peter, T. uhttps://www.cambridge.org/core/journals/antarctic-science/article/mcmurdo-dry-valley-lake-edge-moats-the-ecological-intersection-between-terrestrial-and-aquatic-polar-desert-habitats/31D94DD51E651603482A3AE6E8A52A5701966nas a2200253 4500008004100000022001400041245010100055210006900156260001200225490000700237520119400244653001701438653001301455653002401468653000901492653000901501653002101510100002301531700002401554700002201578700002001600700002101620856007101641 2024 eng d a1523-043000aMeasuring and modelling functional moat area in perennially ice-covered Lake Fryxell, Antarctica0 aMeasuring and modelling functional moat area in perennially icec c10/20240 v563 a

The perennially ice-covered lakes of the McMurdo Dry Valleys (MDVs), Antarctica, are an important reservoir of liquid water in an arid and largely frozen environment. During the austral summer, the margins of these ice covers melt, forming a “moat” of liquid water and thin ice, allowing exchange between lake waters and the atmosphere to occur and serving as an interface between lake, soil, and stream ecosystems. The size of these moats varies from year to year. Here, we have established the first published record of moat area changes at MDVs’ Lake Fryxell through time using manual traces of the moat as observed via satellite imagery. We have also tested a semi-automated approach for measuring moat area and found that it consistently underestimated the manual record, which we suspect may be due to the lower spatial resolution of images used in this versus the manual approach. Finally, we developed a predictive model based on readily available climate data, allowing moat area to be predicted beyond the limits of the satellite-based records. We found that functional moat area varies annually, potentially influencing ecosystem processes in the moats.

10aLake Fryxell10alake ice10aMcMurdo Dry Valleys10amoat10aNDWI10apredictive model1 aStone, Michael, S.1 aSalvatore, Mark, R.1 aDugan, Hilary, A.1 aMyers, Madeline1 aDoran, Peter, T. uhttps://www.tandfonline.com/doi/full/10.1080/15230430.2024.240662602505nas a2200325 4500008004100000022001400041245012700055210006900182260001200251300001800263490000800281520146500289653001701754653003701771653002401808653002401832100002701856700002101883700002301904700002201927700002201949700002501971700002001996700002202016700002202038700002202060700002202082700001402104856006102118 2023 eng d a2169-900300aCauses and characteristics of electrical resistivity variability in shallow (<4 m) soils in Taylor Valley, East Antarctica0 aCauses and characteristics of electrical resistivity variability c02/2023 ae2022JF0066960 v1283 a

Airborne electromagnetic surveys collected in December 2011 and November 2018 and three soil sampling transects were used to analyze the spatial heterogeneity of shallow (<4 m) soil properties in lower Taylor Valley (TV), East Antarctica. Soil resistivities from 2011 to 2018 ranged from ∼33 Ωm to ∼3,500 Ωm with 200 Ωm assigned as an upper boundary for brine-saturated sediments. Elevations below ∼50 m above sea level (masl) typically exhibit the lowest resistivities with resistivity increasing at high elevations on steeper slopes. Soil water content was empirically estimated from electrical resistivities using Archie's Law and range from ∼<1% to ∼68% by volume. An increase in silt- and clay-sized particles at low elevations increases soil porosity but decreases hydraulic conductivity, promoting greater residence times of soil water at low elevations near Lake Fryxell. Soil resistivity variability between 2011 and 2018 shows soils at different stages of soil freeze-thaw cycles, which are caused predominantly by solar warming of soils as opposed to air temperature. This study furthers the understanding of the hydrogeologic structure of the shallow subsurface in TV and identifies locations of soils that are potentially prone to greater rates of thaw and resulting ecosystem homogenization of soil properties from projected increases in hydrological connectivity across the region over the coming decades.

10aactive layer10aairborne electromagnetic surveys10aMcMurdo Dry Valleys10apermafrost dynamics1 aGutterman, William, S.1 aDoran, Peter, T.1 aVirginia, Ross, A.1 aBarrett, John, E.1 aMyers, Krista, F.1 aTulaczyk, Slawek, M.1 aFoley, Neil, T.1 aMikucki, Jill, A.1 aDugan, Hilary, A.1 aGrombacher, Denys1 aBording, Thue, S.1 aAuken, E. uhttps://onlinelibrary.wiley.com/doi/10.1029/2022JF00669600724nas a2200229 4500008004100000022001400041245005500055210005100110260001200161300000800173490000700181653001200188653001200200653001600212653001600228653001200244100002100256700002200277700002700299700002000326856014800346 2023 eng d a0954-102000aExtreme cold (-69.1°C) in the McMurdo Dry Valleys0 aExtreme cold 691°C in the McMurdo Dry Valleys c03/2023 a1-40 v3010aclimate10aextreme10ameteorology10atemperature10aweather1 aDoran, Peter, T.1 aMyers, Krista, F.1 aMcKay, Christopher, P.1 aBromwich, David uhttps://www.cambridge.org/core/journals/antarctic-science/article/extreme-cold-691c-in-the-mcmurdo-dry-valleys/3516874750E5EF96365A26E8D49CA4EC01629nas a2200217 4500008004100000022001400041245007400055210006900129260001200198300001200210490000600222520097000228100002101198700002201219700002401241700001901265700002101284700002101305700001701326856006801343 2022 eng d a2378-224200aBarotropic seiches in a perennially ice-covered lake, East Antarctica0 aBarotropic seiches in a perennially icecovered lake East Antarct c02/2022 a26 - 330 v73 a

Water movement in ice-covered lakes is known to be driven by wind, sediment heat flux, solar radiation, saline density flows, and advective stream discharge. In large ice-covered lakes, wind-induced oscillations have been found to play a major role in horizontal flows. Here, we report recurrent, wind-driven, barotropic seiches in a small lake with a thick (4 m) permanent ice-cover. Between 2010 and 2016, we recorded 10.5- to 13-min oscillations of the hydrostatic water level in Lake Hoare, McMurdo Dry Valleys, East Antarctica, using pressure transducers moored to the lake bottom and suspended from the ice cover. Theoretical calculations showed a barotropic seiche should have a period of 12.6 min. Barotropic seiches were most frequent during high wind events (> 5 m s-1) in winter months (February–November). The period increased during summer months (December–January) when fast ice thinned and melted along the shoreline.

1 aCastendyk, Devin1 aDugan, Hilary, A.1 aGallagher, Hugh, A.1 aPujara, Nimish1 aDoran, Peter, T.1 aPriscu, John, C.1 aLyons, Berry uhttps://aslopubs.onlinelibrary.wiley.com/doi/10.1002/lol2.1022602219nas a2200349 4500008004100000022001400041245012300055210006900178260001200247520113200259653000901391653001901400653001601419653001201435653000901447653001301456100002001469700002501489700001601514700002501530700002101555700001701576700002501593700002501618700002101643700002501664700002601689700002201715700002301737700001801760856009101778 2022 eng d a0006-356800aCross-site comparisons of dryland ecosystem response to climate change in the US Long-Term Ecological Research Network0 aCrosssite comparisons of dryland ecosystem response to climate c c08/20223 a

Long-term observations and experiments in diverse drylands reveal how ecosystems and services are responding to climate change. To develop generalities about climate change impacts at dryland sites, we compared broadscale patterns in climate and synthesized primary production responses among the eight terrestrial, nonforested sites of the United States Long-Term Ecological Research (US LTER) Network located in temperate (Southwest and Midwest) and polar (Arctic and Antarctic) regions. All sites experienced warming in recent decades, whereas drought varied regionally with multidecadal phases. Multiple years of wet or dry conditions had larger effects than single years on primary production. Droughts, floods, and wildfires altered resource availability and restructured plant communities, with greater impacts on primary production than warming alone. During severe regional droughts, air pollution from wildfire and dust events peaked. Studies at US LTER drylands over more than 40 years demonstrate reciprocal links and feedbacks among dryland ecosystems, climate-driven disturbance events, and climate change.

10aANPP10aclimate change10aDisturbance10adrought10aLTER10awildfire1 aHudson, Amy, R.1 aPeters, Debra, P. C.1 aBlair, J.M.1 aChilders, Daniel, L.1 aDoran, Peter, T.1 aGeil, Kerrie1 aGooseff, Michael, N.1 aGross, Katherine, L.1 aHaddad, Nick, M.1 aPastore, Melissa, A.1 aRudgers, Jennifer, A.1 aSala, Osvaldo, E.1 aSeabloom, Eric, W.1 aShaver, Gaius uhttps://academic.oup.com/bioscience/advance-article/doi/10.1093/biosci/biab134/665484001961nas a2200217 4500008004100000245010100041210006900142260001200211300001200223490000700235520124400242653003001486653001101516653002401527653001501551653002101566100002001587700002101607700002201628856009301650 2022 eng d00aValley-floor snowfall in Taylor Valley, Antarctica, from 1995 to 2017: Spring, summer and autumn0 aValleyfloor snowfall in Taylor Valley Antarctica from 1995 to 20 c08/2022 a325-3350 v343 a

We present an analysis of the 20 year snowfall dataset in Taylor Valley and the results of a new snow cover monitoring study. Snowfall has been measured at four sites in Taylor Valley from 1995 to 2017. We focus on valley-floor snowfall when wind does not exceed 5 m s-1, and we exclude winter from our analysis due to poor data quality. Snowfall averaged 11 mm water equivalent (w.e.) from 1995 to 2017 across all stations and ranged from 1 to 58 mm w.e. Standard deviations ranged from 3 to 17 mm w.e., highlighting the strong interannual variability of snowfall in Taylor Valley. During spring and autumn there is a spatial gradient in snowfall such that the coast received twice as much snowfall as more central and inland stations. We identified a changepoint in 2007 from increasing snowfall (3 mm w.e. yr-1) to decreasing snowfall (1 mm w.e. yr-1), which coincides with a shift from decreasing temperature to no detectable temperature trend. Daily camera imagery from 2007 to 2017 augments the snowfall measurements. The camera imagery revealed a near tripling of the average number of days with snow cover from 37 days between 2006 and 2012 to 106 days with snow cover between 2012 and 2017.

10aautomated weather station10acamera10aMcMurdo Dry Valleys10asnow cover10asnow persistence1 aMyers, Madeline1 aDoran, Peter, T.1 aMyers, Krista, F. uhttps://www.cambridge.org/core/product/identifier/S0954102022000256/type/journal_article02981nas a2200253 4500008004100000022001400041245011200055210006900167260001200236300001400248490000700262520216600269653002102435653002602456653002602482100002802508700002202536700002202558700002102580700002202601700001802623700001502641856007102656 2021 eng d a1523-043000aThe magnitude and climate sensitivity of isotopic fractionation from ablation of Antarctic Dry Valley lakes0 amagnitude and climate sensitivity of isotopic fractionation from c12/2021 a352 - 3710 v533 a

There has been extensive research on the effects of evaporation on the isotopic ratio of lacustrine and marine water bodies; however, there are limited data on how ablation or sublimation from lake or sea ice influences the isotopic ratio of the residual water body. This is a challenging problem because there remains uncertainty on the magnitude of fractionation during sublimation and because ablation can involve mixed-phase processes associated with simultaneous sublimation, melting, evaporation, and refreezing. This uncertainty limits the ability to draw quantitative inferences on changing hydrological budgets from stable isotope records in arctic, Antarctic, and alpine lakes. Here, we use in situ measurements of the isotopic ratio of water vapor along with the gradient diffusion method to constrain the isotopic ratio of the ablating ice from two lakes in the McMurdo Dry Valleys, Antarctica. We find that during austral summer, the isotopic fractionation of ablation was insignificant during periods of boundary layer instability that are typical during midday when latent heat is highest. This implies that the loss of mass during these periods did not yield any isotopic enrichment to the residual lake mass. However, fractionation increased after midday when the boundary layer stabilized and the latent heat flux was small. This diurnal pattern was mirrored on synoptic timescales, when following warm and stable conditions latent heat flux was low and dominated by higher fractionation for a few days. We hypothesize that the shifting from negligible to large isotopic fractionation reflects the development and subsequent exhaustion of liquid water on the surface. The results illustrate the complex and nonlinear controls on isotopic fractionation from icy lakes, which implies that the isotopic enrichment from ablation could vary significantly over timescales relevant for changing lake volumes. Future work using water isotope fluxes for longer periods of time and over additional perennial and seasonal ice-covered lake systems is critical for developing models of the isotopic mass balance of arctic and Antarctic lake systems.

10aDry Valley lakes10aisotope fractionation10astable water isotopes1 aBellagamba, Anthony, W.1 aBerkelhammer, Max1 aWinslow, Luke, A.1 aDoran, Peter, T.1 aMyers, Krista, F.1 aDevlin, Shawn1 aHawes, Ian uhttps://www.tandfonline.com/doi/full/10.1080/15230430.2021.200189902224nas a2200229 4500008004100000245016400041210006900205260001200274300000800286490000700294520144700301100002401748700002301772700002201795700001501817700002101832700002201853700002201875700003201897700002101929856004401950 2021 eng d00aMetabolic capacity of the Antarctic cyanobacterium Phormidium pseudopriestleyi that sustains oxygenic photosynthesis in the presence of hydrogen sulfide0 aMetabolic capacity of the Antarctic cyanobacterium IPhormidium p c03/2021 a4260 v123 a

Sulfide inhibits oxygenic photosynthesis by blocking electron transfer between H2O and the oxygen-evolving complex in the D1 protein of Photosystem II. The ability of cyanobacteria to counter this effect has implications for understanding the productivity of benthic microbial mats in sulfidic environments throughout Earth history. In Lake Fryxell, Antarctica, the benthic, filamentous cyanobacterium Phormidium pseudopriestleyi creates a 1–2 mm thick layer of 50 µmol L−1 O2 in otherwise sulfidic water, demonstrating that it sustains oxygenic photosynthesis in the presence of sulfide. A metagenome-assembled genome of P. pseudopriestleyi indicates a genetic capacity for oxygenic photosynthesis, including multiple copies of psbA (encoding the D1 protein of Photosystem II), and anoxygenic photosynthesis with a copy of sqr (encoding the sulfide quinone reductase protein that oxidizes sulfide). The genomic content of P. pseudopriestleyi is consistent with sulfide tolerance mechanisms including increasing psbA expression or directly oxidizing sulfide with sulfide quinone reductase. However, the ability of the organism to reduce Photosystem I via sulfide quinone reductase while Photosystem II is sulfide-inhibited, thereby performing anoxygenic photosynthesis in the presence of sulfide, has yet to be demonstrated. 

1 aLumian, Jessica, E.1 aJungblut, Anne, D.1 aDillon, Megan, L.1 aHawes, Ian1 aDoran, Peter, T.1 aMackey, Tyler, J.1 aDick, Gregory, J.1 aGrettenberger, Christen, L.1 aSumner, Dawn, Y. uhttps://www.mdpi.com/2073-4425/12/3/42602152nas a2200253 4500008004100000245012600041210006900167260001200236300001600248490000700264520133900271100002201610700002101632700002501653700002001678700002201698700001701720700002201737700002201759700001901781700002201800700002301822856005301845 2021 eng d00aThermal legacy of a large paleolake in Taylor Valley, East Antarctica, as evidenced by an airborne electromagnetic survey0 aThermal legacy of a large paleolake in Taylor Valley East Antarc c08/2021 a3577 - 35930 v153 a

Previous studies of the lakes of the McMurdo Dry Valleys have attempted to constrain lake level history, and results suggest the lakes have undergone hundreds of meters of lake level change within the last 20 000 years. Past studies have utilized the interpretation of geologic deposits, lake chemistry, and ice sheet history to deduce lake level history; however a substantial amount of disagreement remains between the findings, indicating a need for further investigation using new techniques. This study utilizes a regional airborne resistivity survey to provide novel insight into the paleohydrology of the region. Mean resistivity maps revealed an extensive brine beneath the Lake Fryxell basin, which is interpreted as a legacy groundwater signal from higher lake levels in the past. Resistivity data suggest that active permafrost formation has been ongoing since the onset of lake drainage and that as recently as 1500–4000 years BP, lake levels were over 60 m higher than present. This coincides with a warmer-than-modern paleoclimate throughout the Holocene inferred by the nearby Taylor Dome ice core record. Our results indicate Mid to Late Holocene lake level high stands, which runs counter to previous research finding a colder and drier era with little hydrologic activity throughout the last 5000 years.

1 aMyers, Krista, F.1 aDoran, Peter, T.1 aTulaczyk, Slawek, M.1 aFoley, Neil, T.1 aBording, Thue, S.1 aAuken, Esben1 aDugan, Hilary, A.1 aMikucki, Jill, A.1 aFoged, Nikolaj1 aGrombacher, Denys1 aVirginia, Ross, A. uhttps://tc.copernicus.org/articles/15/3577/2021/02753nas a2200325 4500008004100000022001400041245011500055210007300170260001200243300001800255490000800273520178400281653001002065653001402075653001602089653000802105653001002113653001002123653001402133653001102147100002802158700002102186700003302207700002202240700002202262700002402284700002902308700002102337856006902358 2021 eng d a2169-895300aYear‐round and long‐term phytoplankton dynamics in Lake Bonney, a permanently ice‐covered Antarctic lake0 aYear‐round and long‐term phytoplankton dynamics in Lake Bonney a c04/2021 ae2020JG0059250 v1263 a

Lake Bonney (McMurdo Dry Valleys, east Antarctica) represents a year‐round refugium for life adapted to permanent extreme conditions. Despite intensive research since the 1960s, due to the logistical constraints posed by 4‐months of 24‐h darkness, knowledge of how the resident photosynthetic microorganisms respond to the polar winter is limited. In addition, the lake level has risen by more than 3 m since 2004: impacts of rapid lake level rise on phytoplankton community structure is also poorly understood. From 2004 to 2015 an in situ submersible spectrofluorometer (bbe FluoroProbe) was deployed in Lake Bonney during the austral summer to quantify the vertical structure of four functional algal groups (green algae, mixed algae, and cryptophytes, cyanobacteria). During the 2013–2014 field season the Fluoroprobe was mounted on autonomous cable‐crawling profilers deployed in both the east and west lobes of Lake Bonney, obtaining the first daily phytoplankton profiles through the polar night. Our findings showed that phytoplankton communities were differentially impacted by physical and chemical factors over long‐term versus seasonal time scales. Following a summer of rapid lake level rise (2010–2011), an increase in depth integrated chlorophyll a (chl‐a) occurred in Lake Bonney caused by stimulation of photoautotrophic green algae. Conversely, peaks in chl‐a during the polar night were associated with an increase in mixotrophic haptophytes and cryptophytes. Collectively our data reveal that phytoplankton groups possessing variable trophic abilities are differentially competitive during seasonal and long‐term time scales owing to periods of higher nutrients (photoautotrophs) versus light/energy limitation (mixotrophs).

10aalgae10aAntarctic10afluorometry10aice10alakes10alight10aprofiling10awinter1 aPatriarche, Jeffrey, D.1 aPriscu, John, C.1 aTakacs-Vesbach, Cristina, D.1 aWinslow, Luke, A.1 aMyers, Krista, F.1 aBuelow, Heather, N.1 aMorgan-Kiss, Rachael, M.1 aDoran, Peter, T. uhttps://agupubs.onlinelibrary.wiley.com/doi/10.1029/2020JG00592502314nas a2200265 4500008004100000245012500041210006900166260001200235490000700247520147000254653001501724653001101739653001701750653001801767653001101785653004001796100002201836700001501858700002301873700002201896700002401918700002101942700002101963856006401984 2020 eng d00aEnergetic and environmental constraints on the community structure of benthic microbial mats in Lake Fryxell, Antarctica0 aEnergetic and environmental constraints on the community structu c02/20200 v963 a

Ecological communities are regulated by the flow of energy through environments. Energy flow is typically limited by access to photosynthetically active radiation (PAR) and oxygen concentration (O2). The microbial mats growing on the bottom of Lake Fryxell, Antarctica, have well-defined environmental gradients in PAR and (O2). We analyzed the metagenomes of layers from these microbial mats to test the extent to which access to oxygen and light controls community structure. We found variation in the diversity and relative abundances of Archaea, Bacteria and Eukaryotes across three (O2) and PAR conditions: high (O2) and maximum PAR, variable (O2) with lower maximum PAR, and low (O2) and maximum PAR. We found distinct communities structured by the optimization of energy use on a millimeter-scale across these conditions. In mat layers where (O2) was saturated, PAR structured the community. In contrast, (O2) positively correlated with diversity and affected the distribution of dominant populations across the three habitats, suggesting that meter-scale diversity is structured by energy availability. Microbial communities changed across covarying gradients of PAR and (O2). The comprehensive metagenomic analysis suggests that the benthic microbial communities in Lake Fryxell are structured by energy flow across both meter- and millimeter-scales.

10aAntarctica10aenergy10aLake Fryxell10amicrobial mat10aOxygen10aPhotosynthetically Active Radiation1 aDillon, Megan, L.1 aHawes, Ian1 aJungblut, Anne, D.1 aMackey, Tyler, J.1 aEisen, Jonathan, A.1 aDoran, Peter, T.1 aSumner, Dawn, Y. uhttps://academic.oup.com/femsec/article/96/2/fiz207/569719602205nas a2200205 4500008004100000245012400041210006900165260001200234300001300246490000700259520150700266100002201773700001501795700002301810700002201833700002401855700002101879700002101900856007801921 2020 eng d00aEnvironmental control on the distribution of metabolic strategies of benthic microbial mats in Lake Fryxell, Antarctica0 aEnvironmental control on the distribution of metabolic strategie c04/2020 ae02310530 v153 a

Ecological theories posit that heterogeneity in environmental conditions greatly affects community structure and function. However, the degree to which ecological theory developed using plant- and animal-dominated systems applies to microbiomes is unclear. Investigating the metabolic strategies found in microbiomes are particularly informative for testing the universality of ecological theories because microorganisms have far wider metabolic capacity than plants and animals. We used metagenomic analyses to explore the relationships between the energy and physicochemical gradients in Lake Fryxell and the metabolic capacity of its benthic microbiome. Statistical analysis of the relative abundance of metabolic marker genes and gene family diversity shows that oxygenic photosynthesis, carbon fixation, and flavin-based electron bifurcation differentiate mats growing in different environmental conditions. The pattern of gene family diversity points to the likely importance of temporal environmental heterogeneity in addition to resource gradients. Overall, we found that the environmental heterogeneity of photosynthetically active radiation (PAR) and oxygen concentration ([O2]) in Lake Fryxell provide the framework by which metabolic diversity and composition of the community is structured, in accordance with its phylogenetic structure. The organization of the resulting microbial ecosystems are consistent with the maximum power principle and the species sorting model.

1 aDillon, Megan, L.1 aHawes, Ian1 aJungblut, Anne, D.1 aMackey, Tyler, J.1 aEisen, Jonathan, A.1 aDoran, Peter, T.1 aSumner, Dawn, Y. uhttps://journals.plos.org/plosone/article?id=10.1371/journal.pone.023105302119nas a2200217 4500008004100000245007600041210006900117260001200186520131800198653001101516653003001527653002801557653002201585653002401607653001201631653001801643100002401661700002101685700002001706856017501726 2020 eng d00aGIS tool to predict photosynthetically active radiation in a Dry Valley0 aGIS tool to predict photosynthetically active radiation in a Dry c04/20203 a

Understanding primary productivity is a core research area of the National Science Foundation's Long-Term Ecological Research Network. This study presents the development of the GIS-based Topographic Solar Photosynthetically Active Radiation (T-sPAR) toolbox for Taylor Valley. It maps surface photosynthetically active radiation using four meteorological stations with ~20 years of data. T-sPAR estimates were validated with ground-truth data collected at Taylor Valley's major lakes during the 2014–15 and 2015–16 field seasons. The average daily error ranges from 0.13 mol photons m-2 day-1 (0.6%) at Lake Fryxell to 3.8 mol photons m-2 day-1 (5.8%) at Lake Hoare. We attribute error to variability in terrain and sun position. Finally, a user interface was developed in order to estimate total daily surface photosynthetically active radiation for any location and date within the basin. T-sPAR improves upon existing toolboxes and models by allowing for the inclusion of a statistical treatment of light attenuation due to cloud cover. The T-sPAR toolbox could be used to inform biological sampling sites based on radiation distribution, which could collectively improve estimates of net primary productivity, in some cases by up to 25%.

10aArcMap10aautomated weather station10adigital elevation model10aice-covered lakes10aMcMurdo Dry Valleys10aR model10aTaylor Valley1 aAcosta, Dimitri, R.1 aDoran, Peter, T.1 aMyers, Madeline uhttps://www.cambridge.org/core/journals/antarctic-science/article/gis-tool-to-predict-photosynthetically-active-radiation-in-a-dry-valley/BD0BE4FF6A8F3DAAF32D69879728707803158nas a2200181 4500008004100000245011200041210006900153260001200222300001200234490000700246520256300253100002402816700002502840700002002865700002102885700002202906856004802928 2020 eng d00aThe seasonal evolution of albedo across glaciers and the surrounding landscape of Taylor Valley, Antarctica0 aseasonal evolution of albedo across glaciers and the surrounding c03/2020 a769-7880 v143 a

The McMurdo Dry Valleys (MDVs) of Antarctica are a polar desert ecosystem consisting of alpine glaciers, ice-covered lakes, streams, and expanses of vegetation-free rocky soil. Because average summer temperatures are close to 0 ∘C, the MDV ecosystem in general, and glacier melt dynamics in particular, are both closely linked to the energy balance. A slight increase in incoming radiation or change in albedo can have large effects on the timing and volume of meltwater. However, the seasonal evolution or spatial variability of albedo in the valleys has yet to fully characterized. In this study, we aim to understand the drivers of landscape albedo change within and across seasons. To do so, a box with a camera, GPS, and shortwave radiometer was hung from a helicopter that flew transects four to five times a season along Taylor Valley. Measurements were repeated over three seasons. These data were coupled with incoming radiation measured at six meteorological stations distributed along the valley to calculate the distribution of albedo across individual glaciers, lakes, and soil surfaces. We hypothesized that albedo would decrease throughout the austral summer with ablation of snow patches and increasing sediment exposure on the glacier and lake surfaces. However, small snow events (<6 mm water equivalent) coupled with ice whitening caused spatial and temporal variability of albedo across the entire landscape. Glaciers frequently followed a pattern of increasing albedo with increasing elevation, as well as increasing albedo moving from east to west laterally across the ablation zone. We suggest that spatial patterns of albedo are a function of landscape morphology trapping snow and sediment, longitudinal gradients in snowfall magnitude, and wind-driven snow redistribution from east to west along the valley. We also compare our albedo measurements to the MODIS albedo product and found that overall the data have reasonable agreement. The mismatch in spatial scale between these two datasets results in variability, which is reduced after a snow event due to albedo following valley-scale gradients of snowfall magnitude. These findings highlight the importance of understanding the spatial and temporal variability in albedo and the close coupling of climate and landscape response. This new understanding of landscape albedo can constrain landscape energy budgets, better predict meltwater generation on from MDV glaciers, and how these ecosystems will respond to changing climate at the landscape scale.

1 aBergstrom, Anna, J.1 aGooseff, Michael, N.1 aMyers, Madeline1 aDoran, Peter, T.1 aCross, Julian, M. uhttps://www.the-cryosphere.net/14/769/2020/01789nas a2200205 4500008004100000245008500041210006900126260001200195520112400207653001601331653001801347653001001365653001501375653001601390100001901406700002101425700002201446700002101468856009401489 2020 eng d00aSubglacial brine flow and wind-induced internal waves in Lake Bonney, Antarctica0 aSubglacial brine flow and windinduced internal waves in Lake Bon c02/20203 a

Brine beneath Taylor Glacier has been proposed to enter the proglacial west lobe of Lake Bonney (WLB) as well as from Blood Falls, a surface discharge point at the Taylor Glacier terminus. The brine strongly influences the geochemistry of the water column of WLB. Year-round measurements from this study are the first to definitively identify brine intrusions from a subglacial entry point into WLB. Furthermore, we excluded input from Blood Falls by focusing on winter dynamics when the absence of an open water moat prevents surface brine entry. Due to the extremely high salinities below the chemocline in WLB, density stratification is dominated by salinity, and temperature can be used as a passive tracer. Cold brine intrusions enter WLB at the glacier face and intrude into the water column at the depth of neutral buoyancy, where they can be identified by anomalously cold temperatures at that depth. High-resolution measurements also reveal under-ice internal waves associated with katabatic wind events, a novel finding that challenges long-held assumptions about the stability of the WLB water column.

10aDry valleys10ahypersalinity10alakes10aproglacial10atemperature1 aLawrence, Jade1 aDoran, Peter, T.1 aWinslow, Luke, A.1 aPriscu, John, C. uhttps://www.cambridge.org/core/services/aop-cambridge-core/content/view/S095410202000003601525nas a2200145 4500008004100000245008300041210006900124260001200193490000800205520102800213100002201241700002101263700002101284856007401305 2019 eng d00aPrediction of ice-free conditions for a perennially ice-covered Antarctic lake0 aPrediction of icefree conditions for a perennially icecovered An c02/20190 v1243 a

Although perennially ice-covered Antarctic lakes have experienced variable ice thicknesses over the past several decades, future ice thickness trends and associated aquatic biological responses under projected global warming remain unknown. Heat stored in the water column in chemically stratified Antarctic lakes that have mid-depth temperature maxima, can significantly influence the ice thickness trends via upward heat flux to the ice/water interface. We modeled ice thickness of the west of lobe of Lake Bonney, Antarctica based on possible future climate scenarios utilizing a 1D thermodynamic model that accounts for surface radiative fluxes as well as the heat flux associated with the temperature evolution of the water column. Model results predict that the ice cover of Lake Bonney will shift from perennial to seasonal within one to four decades, a change that will drastically influence ecosystem processes within the lake.

1 aObryk, Maciek, K.1 aDoran, Peter, T.1 aPriscu, John, C. uhttps://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JF00475602017nas a2200133 4500008004100000245011800041210006900159260005700228490000900285520149000294100002001784700002101804856005801825 2019 eng d00aSpatiotemporal impact of snow on underwater photosynthetically active radiation in Taylor Valley, East Antarctica0 aSpatiotemporal impact of snow on underwater photosynthetically a aBaton Rouge, LAbLouisiana State Universityc08/20190 vM.S.3 a

The role of snow on underwater photosynthetically active radiation (UW PAR) in the McMurdo Dry Valleys (MDVs) has been understudied due to lack of a detailed snowfall record. Research has shown that a relationship between snow cover and UW PAR exists, but the extent has never been evaluated in great detail. Although annual snowfall values in the MDVs are low (3 to 50 mm water equivalent annually), trends of increasing snowfall on the continent under future warming conditions could lead to an increased role for snow in regulating UW PAR (and associated primary productivity). Here, I discuss evidence from the snowfall record, surface PAR, and UW PAR, of the influence of snowfall on UW PAR in the major lakes of Taylor Valley. This study aims to quantify the spatiotemporal impact of lake ice snow packs on UW PAR in Taylor Valley from field surveys, long-term UW PAR, and meteorological data. Lake Fryxell has the strongest seasonality to precipitation, which decreases inland. On average, Lake Fryxell also has the most days with snow cover on the lake ice. Lake Hoare is experiencing an increase in Fall snow persistence since the 2007 snow year. Snow less than 0.5 mm snow water equivalent (SWE) can suppress UW PAR by 40%. The calendar day that snow falls often determines whether phototrophs will switch from photosynthesis to respiration, which suggests the importance to seasonality in determining the impact of snow on photoautotrophs and lake-wide carbon budget.

1 aMyers, Madeline1 aDoran, Peter, T. uhttps://digitalcommons.lsu.edu/gradschool_theses/496501630nas a2200169 4500008004100000245008200041210006900123260001200192490000600204520109200210100002201302700002401324700002101348700001701369700001601386856005801402 2018 eng d00aDrivers of solar radiation variability in the McMurdo Dry Valleys, Antarctica0 aDrivers of solar radiation variability in the McMurdo Dry Valley c03/20180 v83 a

 

Annually averaged solar radiation in the McMurdo Dry Valleys, Antarctica has varied by over 20 W m−2 during the past three decades; however, the drivers of this variability are unknown. Because small differences in radiation are important to water availability and ecosystem functioning in polar deserts, determining the causes are important to predictions of future desert processes. We examine the potential drivers of solar variability and systematically eliminate all but stratospheric sulfur dioxide. We argue that increases in stratospheric sulfur dioxide increase stratospheric aerosol optical depth and decrease solar intensity. Because of the polar location of the McMurdo Dry Valleys (77–78°S) and relatively long solar ray path through the stratosphere, terrestrial solar intensity is sensitive to small differences in stratospheric transmissivity. Important sources of sulfur dioxide include natural (wildfires and volcanic eruptions) and anthropogenic emission.

 

1 aObryk, Maciek, K.1 aFountain, Andrew, G1 aDoran, Peter, T.1 aLyons, Berry1 aEastman, R. uhttp://www.nature.com/articles/s41598-018-23390-7.pdf02633nas a2200133 4500008004100000245016300041210006900204260005700273490000900330520205900339100002202398700002102420856005802441 2018 eng d00aGroundwater and thermal legacy of a large paleolake in Taylor Valley, East Antarctica as evidenced by airborne electromagnetic and sedimentological techniques0 aGroundwater and thermal legacy of a large paleolake in Taylor Va aBaton Rouge, LAbLouisiana State Universityc07/20180 vM.S.3 a

During the Last Glacial Maximum, grounded ice in the Ross Sea extended into the otherwise ice-free McMurdo Dry Valleys, creating a series of large ice dammed paleolakes. Grounded ice within the mouth of Taylor Valley allowed for lake levels to reach elevations not possible at modern day and formed what is known as Glacial Lake Washburn (GLW). GLW extended from the eastern portion of Taylor Valley roughly 20 km west to a level ~300 m higher than modern day Lake Fryxell. The formation and existence of GLW has been debated, though previous studies correlate the timing of GLW with early Holocene grounded ice. Evidence of GLW has largely been constrained to the interpretation of glacial deposits and fluvial features such as lacustrine deposits, strandlines, and preserved paleodeltas. GIS and remote sensing techniques paired with regional resistivity data provide new insight into the paleohydrology of the region.

To quantify the extent of GLW, paleodelta locations were mapped using high resolution LiDAR digital elevation models and satellite imagery. Delta topset elevations were correlated between three streams in Fryxell basin to determine paleolake levels. Additionally, mean resistivity maps generated from airborne electromagnetic survey data (SkyTEM) reveal an extensive groundwater system within Fryxell basin which is interpreted as a legacy groundwater signal from GLW. Resistivity data suggests that active permafrost formation has been ongoing since onset of lake drainage, and that lake levels were over 60 m higher than modern only 1,000 – 2,000 yr BP. This coincides with a warmer than modern paleoclimate inferred by ice core records, indicating a dynamic hydrological system that is highly sensitive to small changes in climate. As global temperatures increase, Lake Fryxell will continue to experience highly variable lake levels. Lakes and groundwater within the McMurdo Dry Valleys are critical to understanding impacts on the broader ecosystem which is largely driven by the availability of liquid water.

1 aMyers, Krista, F.1 aDoran, Peter, T. uhttps://digitalcommons.lsu.edu/gradschool_theses/477602508nas a2200181 4500008004100000245017000041210006900211260001200280300001600292490000700308520183400315100002302149700002102172700002202193700002302215700002102238856006702259 2018 eng d00aThe physical limnology of a permanently ice-covered and chemically stratified Antarctic lake using high resolution spatial data from an autonomous underwater vehicle0 aphysical limnology of a permanently icecovered and chemically st c05/2018 a1234 - 12520 v633 a

We used an Environmentally Non-Disturbing Under-ice Robotic ANtarctic Explorer to make measurements of conductivity and temperature in Lake Bonney, a chemically stratified, permanently ice-covered Antarctic lake that abuts Taylor Glacier, an outlet glacier from the Polar Plateau. The lake is divided into two lobes – East Lobe Bonney (ELB) and West Lobe Bonney (WLB), each with unique temperature and salinity profiles. Most of our data were collected in November 2009 from WLB to examine the influence of the Taylor Glacier on the structure of the water column. Temperatures adjacent to the glacier face between 20 m and 22 m were 38C colder than in the rest of WLB, due to latent heat transfer associated with melting of the submerged glacier face and inflow of cold brines that originate beneath the glacier. Melting of the glacier face into the salinity gradient below the chemocline generates a series of nearly horizontal intrusions into WLB that were previously documented in profiles measured with 3 cm vertical resolution in 1990–1991. WLB and ELB are connected by a narrow channel through which water can be exchanged over a shallow sill that controls the position of the chemocline in WLB. A complex exchange flow appears to exist through the narrows, driven by horizontal density gradients and melting at the glacier face. Superimposed on the exchange is a net west- to-east flow generated by the higher volume of meltwater inflows to WLB. Both of these processes can be expected to be enhanced in the future as more meltwater is produced. 

1 aSpigel, Robert, H.1 aPriscu, John, C.1 aObryk, Maciek, K.1 aStone, William, C.1 aDoran, Peter, T. uhttp://onlinelibrary.wiley.com/wol1/doi/10.1002/lno.10768/full00851nas a2200265 4500008004100000245009100041210006900132260001200201300001400213490000600227100002500233700002200258700001700280700002100297700002400318700001700342700002400359700002100383700002000404700003300424700003100457700002300488700002000511856005400531 2017 eng d00aDecadal ecosystem response to an anomalous melt season in a polar desert in Antarctica0 aDecadal ecosystem response to an anomalous melt season in a pola c09/2017 a1334-13380 v11 aGooseff, Michael, N.1 aBarrett, John, E.1 aAdams, Byron1 aDoran, Peter, T.1 aFountain, Andrew, G1 aLyons, Berry1 aMcKnight, Diane, M.1 aPriscu, John, C.1 aSokol, Eric, R.1 aTakacs-Vesbach, Cristina, D.1 aVandegehuchte, Martijn, L.1 aVirginia, Ross, A.1 aWall, Diana, H. uhttps://www.nature.com/articles/s41559-017-0253-002279nas a2200133 4500008004100000245013700041210006900178260004800247490000900295520174300304100001902047700002102066856005802087 2017 eng d00aEvidence of subglacial brine inflow and wind-induced mixing from high resolution temperature measurements in Lake Bonney, Antarctica0 aEvidence of subglacial brine inflow and windinduced mixing from  aBaton Rouge, LAbLouisiana State University0 vM.S.3 a

Hypersaline brine beneath Taylor Glacier enters proglacial West Lobe Lake Bonney (WLB) subglacially as well as from Blood Falls, a surface discharge point at the Taylor Glacier terminus. The brine strongly influences the water column of WLB. Because of the extremely high salinities below the chemocline in WLB, density is determined almost entirely by salinity and temperature can be used as a passive tracer. Cold brine intrusions enter WLB at the glacier face and intrude in to the water column at the depth of neutral buoyancy, where they can be identified by anomalously cold temperatures at that depth. This study is the first to definitively identify subglacial brine intrusions in WLB, since the absence of an open water moat in the winter prevents brine entry from the surface at Blood Falls. High resolution thermistors and CTDs deployed year-round beneath the perennial ice cover demonstrate that brine intrusions can influence the thermal stratification of the water column near the glacier terminus for the majority of the year, and that the effects diminish with distance from the glacier terminus. High volumes of brine inflow alter the density stratification of the water column at the depth of the intrusion and cause turbulent mixing near the glacier terminus. High resolution measurements also reveal internal water movements associated with katabatic wind events, a novel finding that challenges long held assumptions about the stability of the WLB water column. The long term records of Blood Falls flow and of temperature anomalies in WLB indicate that brine release from the subglacial system has been a persistent feature in the region for decades, with implications for the geochemistry and biology of WLB.

1 aLawrence, Jade1 aDoran, Peter, T. uhttps://digitalcommons.lsu.edu/gradschool_theses/434300637nas a2200157 4500008004100000245015300041210007000194260001200264300001200276490000700288100002200295700002100317700002100338700002700359856009300386 2017 eng d00aThe influence of föhn winds on Glacial Lake Washburn and palaeotemperatures in the McMurdo Dry Valleys, Antarctica, during the Last Glacial Maximum0 ainfluence of föhn winds on Glacial Lake Washburn and palaeotempe c10/2017 a457-4670 v291 aObryk, Maciek, K.1 aDoran, Peter, T.1 aWaddington, E.D.1 aMcKay, Christopher, P. uhttps://www.cambridge.org/core/product/identifier/S0954102017000062/type/journal_article02953nas a2200169 4500008004100000245010500041210006900146260001200215300001400227490000700241520241100248100001502659700002302674700002202697700002102719856004302740 2016 eng d00aGrowth dynamics of a laminated microbial mat in response to variable irradiance in an Antarctic lake0 aGrowth dynamics of a laminated microbial mat in response to vari c02/2016 a396 - 4100 v613 a
  1. Laminated microbial mats are important ecosystem components of perennially ice-covered Antarctic dry valley lakes. In order to understand better their response to changing environment, we made observations and carried out a manipulation experiment to determine their response to variations in irradiance in Lake Hoare (77°38′ S, 162°53′ E).
  2. Ice transparency was the most variable parameter that affected benthic light dose, both spatially and between years. Patterns of lamina accrual corresponded to irradiance history, with laminae that were initiated in high transmission years thicker than those from low transmission years.
  3. A shading experiment confirmed that accrual of lamina thickness, calcite precipitation and ash-free dry mass were determined by irradiance, but photosynthetic biomass and phototrophic species composition were less affected.
  4. Buried laminae decomposed only slowly over time, with potentially viable phototrophs many laminae down into the microbial mat. Decay rate increased only slightly with shading.
  5. We conclude that the microbial mats in Lake Hoare are characterised by remarkable stability, with slow accumulation rates and turnover of biomass over time. Photosynthetic biomass and species composition appeared to be stable across long time periods, with interannual variation in lamination pattern due to differential accumulation of extracellular polysaccharide and representing the visible expression of annual growth conditions.
1 aHawes, Ian1 aJungblut, Anne, D.1 aObryk, Maciek, K.1 aDoran, Peter, T. uhttp://doi.wiley.com/10.1111/fwb.1271500649nas a2200169 4500008004100000022001400041245017800055210006900233260001200302300001600314490000700330100002200337700002300359700002200382700002100404856005400425 2016 eng d a0016-803300aHigh-resolution ground-penetrating radar profiles of perennial lake ice in the McMurdo Dry Valleys, Antarctica: Horizon attributes, unconformities, and subbottom penetration0 aHighresolution groundpenetrating radar profiles of perennial lak c01/2016 aWA13 - WA200 v811 aDugan, Hilary, A.1 aArcone, Steven, A.1 aObryk, Maciek, K.1 aDoran, Peter, T. uhttp://library.seg.org/doi/10.1190/geo2015-0159.101797nas a2200253 4500008004100000022001400041245007900055210006900134260001200203300001400215490000700229520101000236100002401246700001601270700001701286700002101303700002001324700002501344700002201369700002101391700002801412700002301440856008001463 2016 eng d a0006-356800aThe Impact of a Large-Scale Climate Event on Antarctic Ecosystem Processes0 aImpact of a LargeScale Climate Event on Antarctic Ecosystem Proc c10/2016 a848 - 8630 v663 a

Extreme climate and weather events, such as a drought, hurricanes, or ice storms, can strongly imprint ecosystem processing and may alter ecosystem structure. Ecosystems in extreme environments are particularly vulnerable because of their adaptation to severe limitations in energy, water, or nutrients. The vulnerability can be expressed as a relatively long-lasting ecosystem response to a small or brief change in environmental conditions. Such an event occurred in Antarctica and affected two vastly different ecosystems: a marine-dominated coastal system and a terrestrial polar desert. Both sites experienced winds that warmed air temperatures above the 0°C threshold, resulting in extensive snow and ice melt and triggering a series of cascading effects through the ecosystems that are continuing to play out more than a decade later. This highlights the sensitivity of Antarctic ecosystems to warming events, which should occur more frequently in the future with global climate warming.

1 aFountain, Andrew, G1 aSaba, Grace1 aAdams, Byron1 aDoran, Peter, T.1 aFraser, William1 aGooseff, Michael, N.1 aObryk, Maciek, K.1 aPriscu, John, C.1 aStammerjohn, Sharon, E.1 aVirginia, Ross, A. uhttp://academic.oup.com/bioscience/article-pdf/66/10/848/7510601/biw110.pdf00761nas a2200241 4500008004100000022001400041245009900055210006900154260001200223300001400235490000700249100002300256700001500279700002200294700001800316700002100334700002100355700002400376700001900400700002700419700001800446856005500464 2016 eng d a0099-224000aMicrobial Mat Communities along an Oxygen Gradient in a Perennially Ice-Covered Antarctic Lake0 aMicrobial Mat Communities along an Oxygen Gradient in a Perennia c01/2016 a620 - 6300 v821 aJungblut, Anne, D.1 aHawes, Ian1 aMackey, Tyler, J.1 aKrusor, Megan1 aDoran, Peter, T.1 aSumner, Dawn, Y.1 aEisen, Jonathan, A.1 aHillman, Colin1 aGoroncy, Alexander, K.1 aStams, A., J. uhttp://aem.asm.org/lookup/doi/10.1128/AEM.02699-1502208nas a2200181 4500008004100000022001400041245010400055210006900159260001200228300001100240520160100251100002201852700002101874700001801895700002701913700002101940856006501961 2016 eng d a0022-143000aModeling the thickness of perennial ice covers on stratified lakes of the Taylor Valley, Antarctica0 aModeling the thickness of perennial ice covers on stratified lak c06/2016 a1 - 103 a
A 1-D ice cover model was developed to predict and constrain drivers of long-term ice thickness trends in chemically stratified lakes of Taylor Valley, Antarctica. The model is driven by surface radiative heat fluxes and heat fluxes from the underlying water column. The model successfully reproduced 16 a (between 1996 and 2012) of ice thickness changes for the west lobe of Lake Bonney (average ice thickness = 3.53 m) and Lake Fryxell (average ice thickness = 4.22 m). Long-term ice thickness trends require coupling with the thermal structure of the water column. The heat stored within the temperature maximum of lakes exceeding a liquid water column depth of 20 m can either impede or facilitate ice thickness change depending on the predominant climatic trend (cooling or warming). As such, shallow (<20 m deep water columns) perennially ice-covered lakes without deep temperature maxima are more sensitive indicators of climate change. The long-term ice thickness trends are a result of surface energy flux and heat flux from the deep temperature maximum in the water column, the latter of which results from absorbed solar radiation.

 

1 aObryk, Maciek, K.1 aDoran, Peter, T.1 aHicks, J., A.1 aMcKay, Christopher, P.1 aPriscu, John, C. uhttp://www.journals.cambridge.org/abstract_S002214301600069101330nas a2200193 4500008004100000245009800041210006900139260004000208490000900248520071900257653001500976653001400991653001501005653001701020653001901037100002101056700002101077856003801098 2016 eng d00aNoble Gas Radioisotope Constraints on Water Residence Time and Solvent Sources in Lake Bonney0 aNoble Gas Radioisotope Constraints on Water Residence Time and S aChicago, ILbUniversity of Illinois0 vM.S.3 a

A noble gas radionuclide analysis of perennially ice covered West Lake Bonney was performed in order to determine water residence time and ice cover timing. Bulk gas samples were collected at four depths in the lake. Krypton and argon gases were selectively isolated from the bulk gas and measurements of 81Kr, 85Kr and 39Ar were made. Radiokrypton and radioargon analyses yielded lower limit ages of 78 to 285 years, significantly younger than expected based on previous dating efforts. It was determined that these new data do not invalidate previous work, but instead offer new insight into the timing of the most recent episode of direct communication between the atmosphere and West Lake Bonney waters.

10aAntarctica10anoble gas10aradioargon10aradiokrypton10aresidence time1 aCronin, Kyle, D.1 aDoran, Peter, T. uhttp://hdl.handle.net/10027/2157000943nas a2200253 4500008004100000022001400041245008700055210006900142260001600211300001400227490000700241100002200248700002100270700002600291700002500317700001200342700002900354700002100383700002100404700002800425700002700453700002200480856018700502 2016 eng d a0006-356800aResponses of Antarctic Marine and Freshwater Ecosystems to Changing Ice Conditions0 aResponses of Antarctic Marine and Freshwater Ecosystems to Chang cJan-10-2016 a864 - 8790 v661 aObryk, Maciek, K.1 aDoran, Peter, T.1 aFriedlaender, Ari, S.1 aGooseff, Michael, N.1 aLi, Wei1 aMorgan-Kiss, Rachael, M.1 aPriscu, John, C.1 aSchofield, Oscar1 aStammerjohn, Sharon, E.1 aSteinberg, Deborah, K.1 aDucklow, Hugh, W. uhttps://academic.oup.com/bioscience/article-lookup/doi/10.1093/biosci/biw109https://academic.oup.com/bioscience/article/66/10/864/2415532/Responses-of-Antarctic-Marine-and-Freshwater04921nas a2200181 4500008004100000022001400041245008200055210006900137260001200206300001300218520434700231100002104578700001504599700002204614700002304636700002104659856005904680 2015 eng d a0091-761300aAntarctic microbial mats: A modern analog for Archean lacustrine oxygen oases0 aAntarctic microbial mats A modern analog for Archean lacustrine  c10/2015 aG36966.13 a

The evolution of oxygenic photosynthesis was the most important geochemical event in

Earth history, causing the Great Oxidation Event (GOE) ~2.4 b.y. ago. However, evidence is mixed as to whether O2 production occurred locally as much as 2.8 b.y. ago, creating O2 oases, or initiated just prior to the GOE. The biogeochemical dynamics of possible O2 oases have been poorly constrained due to the absence of modern analogs. However, cyanobacteria in microbial mats in a perennially anoxic region of Lake Fryxell, Antarctica, create a 1–2 mm O2-containing layer in the upper mat during summer, providing the first known modern analog for formation of benthic O2 oases. In Lake Fryxell, benthic cyanobacteria are present below the oxycline in the lake. Mat photosynthesis rates were slow due to low photon flux rate (1–2 μmol m-2 s-1) under thick ice cover, but photosynthetic O2 production was sufficient to sustain up to 50 μmol O2 L-1, sandwiched between anoxic overlying water and anoxic sedi- ments. We hypothesize that Archean cyanobacteria could have similarly created O2 oases in benthic mats prior to the GOE. Analogous mats may have been at least partly responsible for geological evidence of oxidative weathering prior to the GOE, and habitats such as Lake Fryxell provide natural laboratories where the impact of benthic O2 oases on biogeochemical signatures can be investigated. 

 

1 aSumner, Dawn, Y.1 aHawes, Ian1 aMackey, Tyler, J.1 aJungblut, Anne, D.1 aDoran, Peter, T. uhttp://geology.gsapubs.org/lookup/doi/10.1130/G36966.101657nas a2200229 4500008004100000245008700041210006900128260001600197300000900213490000600222520097300228100002201201700001401223700001601237700002301253700001701276700002201293700002101315700002201336700001401358856005501372 2015 eng d00aDeep groundwater and potential subsurface habitats beneath an Antarctic dry valley0 aDeep groundwater and potential subsurface habitats beneath an An cApr-04-2017 a68310 v63 aThe occurrence of groundwater in Antarctica, particularly in the ice-free regions and along the coastal margins is poorly understood. Here we use an airborne transient electromagnetic (AEM) sensor to produce extensive imagery of resistivity beneath Taylor Valley. Regional-scale zones of low subsurface resistivity were detected that are inconsistent with the high resistivity of glacier ice or dry permafrost in this region. We interpret these results as an indication that liquid, with sufficiently high solute content, exists at temperatures well below freezing and considered within the range suitable for microbial life. These inferred brines are widespread within permafrost and extend below glaciers and lakes. One system emanates from below Taylor Glacier into Lake Bonney and a second system connects the ocean with the eastern 18 km of the valley. A connection between these two basins was not detected to the depth limitation of the AEM survey (~350 m).1 aMikucki, Jill, A.1 aAuken, E.1 aTulaczyk, S1 aVirginia, Ross, A.1 aSchamper, C.1 aSørensen, K., I.1 aDoran, Peter, T.1 aDugan, Hilary, A.1 aFoley, N. uhttp://www.nature.com/doifinder/10.1038/ncomms783104908nas a2200193 4500008004100000022001300041245008800054210006900142260001600211300001200227490000700239520413400246100002304380700002204403700002004425700001804445700002104463856023004484 2015 eng d a0883292700aReconstructing the evolution of Lake Bonney, Antarctica using dissolved noble gases0 aReconstructing the evolution of Lake Bonney Antarctica using dis cJan-07-2015 a46 - 610 v583 a

Lake Bonney (LB), located in Taylor valley, Antarctica, is a perennially ice-covered lake with two lobes, West Lake Bonney (WLB) and East Lake Bonney (ELB), which are separated by a narrow ridge. Numerous studies have attempted to reconstruct the evolution of LB because of its sensitivity to climatic variations and the lack of reliable millennial-scale continental records of climate in this region of Antarctica. However, these studies are limited by the availability of accurate lacustrine chronologies. Here, we attempt to better constrain the chronology of LB and thus, the evolution of past regional climate by estimating water residence times based on He, Ne and Ar concentrations and isotopic ratios in both WLB and ELB.

3He and 4He excesses up to two and three orders of magnitude and 35–150 times the atmospheric values are observed for WLB and ELB samples, respectively. In comparison, while measured 40Ar/36Ar ratios are atmospheric (∼295.5) in ELB, WLB samples display 40Ar/36Ar ratios of up to ∼315 reflecting addition of radiogenic 40Ar. Both4He and 40Ar excesses clearly identify the addition of subglacial discharge (SGD) from underneath Taylor Glacier into WLB at depths of 25 m and 35 m. He isotopic ratios suggest that He excesses are predominantly crustal (>93%) in origin with small mantle contributions (<7%). These crustal 4He and 40Ar excesses are used together with basement rock production rates of these isotopes to derive first-order approximations of water residence times for both lobes. Numerous factors capable of affecting water residence times are evaluated and corrected 4He and 40Ar water ages are used to place further constrains into the reconstruction of both WLB and ELB history. Combined 4He and 40Ar ages in WLB suggest maximum water residence times of ∼250 kyrs BP. These results support the presence of remnant water from proglacial lakes that existed during Marine Isotope Stage 7 (160–240 kyrs) in WLB, in agreement with previous studies. In comparison, 4He ages in ELB are much younger (<27 kyrs BP) and display a complex evolutionary history that is very different from WLB. 4He ages also suggest that the ELB ice cover formed significantly earlier (∼1.5 kyrs BP) than previously reported. The timing of these hydrologic changes in ELB appears to correspond to regional and global climatic events that are recorded in both the Taylor Dome ice-core record as well as in other Dry Valley Lakes.

1 aWarrier, Rohit, B.1 aCastro, Clara, M.1 aHall, Chris, M.1 aKenig, Fabien1 aDoran, Peter, T. uhttp://linkinghub.elsevier.com/retrieve/pii/S088329271500044Xhttp://api.elsevier.com/content/article/PII:S088329271500044X?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S088329271500044X?httpAccept=text/plain02038nas a2200181 4500008004100000022001400041245011000055210006900165260001200234300000900246490001400255520146300269100001801732700001501750700002201765700002101787856004801808 2015 eng d a1365-207900aSediment transport dynamics on an ice-covered lake: The “floating” boulders of Lake Hoare, Antarctica0 aSediment transport dynamics on an icecovered lake The floating b c04/2015 a1-120 vfirstview3 a

Between 1995 and 2011 a global positioning system survey of 13 boulders and three ablation stakes (long stakes frozen in the ice) on the frozen surface of Lake Hoare was undertaken. Data interpretation illustrates complexities of post-depositional transport dynamics of boulders. Earlier studies on comparable datasets have suggested linear ‘conveyor’ type transport mechanisms for lake surface boulders. Yet explanations for non-linear boulder displacements or ‘walks’ and the mechanisms responsible for movements are inadequate. Two modes of boulder specific movement were observed. First, localized changes in the ice surface promote individual boulder movement (rolling). Second, ice rafting, which indicates the displacement of ‘plates’ of lake ice on which the boulder is located. Ablation stakes used as fixed survey control points support the hypothesis that ice cover moves as discrete plates rather than as a single homogenous mass. Factors that create the conditions to generate either of the two modes of movement may be related to location specific energy budgets. A relationship between average orientations and prevailing wind direction was also observed. The investigation describes the local-scale behaviour of surveyed boulders, and offers methodologies and interpretive frameworks for additional studies of modern and ancient sediment transportation dynamics in Antarctic lacustrine environments.

1 aAllen, P., P.1 aHewitt, R.1 aObryk, Maciek, K.1 aDoran, Peter, T. uhttp://dx.doi.org/10.1017/S095410201400055802177nas a2200217 4500008004100000022001300041245014200054210006900196260001600265300001100281490000700292520131900299100002201618700002201640700002401662700002101686700002101707700003301728700002101761856017701782 2014 eng d a0025332400aAutonomous Year-Round Sampling and Sensing to Explore the Physical and Biological Habitability of Permanently Ice-Covered Antarctic Lakes0 aAutonomous YearRound Sampling and Sensing to Explore the Physica cJan-09-2014 a8 - 170 v483 a

The lakes of the McMurdo Dry Valleys, Antarctica, are some of the only systems on our planet that are perennially ice-covered and support year-round metabolism. As such, these ecosystems can provide important information on conditions and life in polar regions on Earth and on other icy worlds in our solar system. Working in these extreme environments of the Dry Valleys poses many challenges, particularly with respect to data collection during dark winter months when logistical constraints make fieldwork difficult. In this paper, we describe the motivation, design, and challenges for this recently deployed instrumentation in Lake Bonney, a lake that has been the subject of summer research efforts for more than 40 years. The instrumentation deployed includes autonomous water, phytoplankton, and sediment samplers as well as cable-mounted profiling platforms with dissolved gas and fluorometry sensors. Data obtained from these instruments will allow us, for the first time, to define the habitability of this environment during the polar night. We include lessons learned during deployment and recommendations for effective instrument operation in these extreme conditions.

1 aWinslow, Luke, A.1 aDugan, Hilary, A.1 aBuelow, Heather, N.1 aCronin, Kyle, D.1 aPriscu, John, C.1 aTakacs-Vesbach, Cristina, D.1 aDoran, Peter, T. uhttp://openurl.ingenta.com/content/xref?genre=article&issn=0025-3324&volume=48&issue=5&spage=8http://www.ingentaconnect.com/content/mts/mtsj/2014/00000048/00000005/art0000202341nas a2200157 4500008004100000245017500041210006900216260001200285300001200297490000700309520168800316100001502004700001402019700002102033856012902054 2014 eng d00aEstimating photosynthetic activity in microbial mats in an ice-covered Antarctic lake using automated oxygen microelectode profiling and variable chlorophyll fluorescence0 aEstimating photosynthetic activity in microbial mats in an iceco c08/2014 a674-6880 v593 a An automated oxygen microprofiler measured a positive flux of oxygen from microbial mats in ice-covered Lake Hoare, Antarctica, from noon, at a photon flux of 20 µmol m−2 s−1, through to midnight (< 2 µmol photons m−2 s−1). Daily average oxygen flux was 200 µmol m−2 h−1; and, whereas it was maximal at noon, when a 10 mm broad concentration peak was observed 5 mm below the mat surface, flux correlated only weakly with irradiance. In contrast, relative electron transfer rate, estimated from variable chlorophyll fluorescence, suggested a linear relationship between photosystem activity and irradiance. This contradiction arose because of the conjunction of photosynthetic production of oxygen deep into these transparent, gelatinous mats (diel oxygen change was observed to 17 mm depth) and oxygen diffusion rates too slow to allow equilibration of oxygen concentration profiles with instantaneous production and consumption of oxygen. To confirm this, we developed a mathematical simulation of oxygen dynamics that included diffusion, photosynthesis, and respiration. The simulation further indicated that (1) net oxygen evolution is light limited is and confined to the upper few millimeters of the mat, (2) below 5–7 mm, respiration balanced photosynthesis, (3) below 17 mm, respiration and photosynthesis approached zero, even though organic carbon and dissolved oxygen were present, and (4) photosynthesis deep into the mat was dependent on high light transmission through the gelatinous matrix. These conclusions are consistent with current understanding of mat growth dynamics and point to approaches for long-term analysis of microbial mat productivity.1 aHawes, Ian1 aGiles, H.1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/estimating-photosynthetic-activity-microbial-mats-ice-covered-antarctic-lake-using-automated02215nas a2200205 4500008004100000245009200041210006900133260004000202490001000242520158200252653001501834653001001849653001301859653002401872653001601896653001601912100002201928700002101950856003801971 2014 eng d00aGeophysics, Water Balance, and History of Thick Perennial Ice Covers on Antarctic Lakes0 aGeophysics Water Balance and History of Thick Perennial Ice Cove aChicago, ILbUniversity of Illinois0 vPh.D.3 a

Antarctic lakes are studied as sentinels of future change, for paleolimnological records contained in the sediments, and as habitats for the simple food webs that can exist in inhospitable environments. Understanding how lakes are formed and are sustained in response to landscape and climate conditions is critical in addressing the aforementioned research themes. This thesis is governed by the overarching hypothesis that an understanding of hydrologic and sediment transport processes associated with lake ice formation and preservation can be used to reveal past climatic changes, and further our awareness of current changes in climate and water balance in the McMurdo Dry Valleys of Antarctica. The first chapter focuses on water loss from closed basin lakes in Taylor Valley, Antarctica, and presents updated estimates of sublimation and ablation rates from long-term empirical measurements. The second and third chapters address the formation of Lake Vida, Antarctica. The former investigates the accretion of a 27 m ice cover, and considers the origin of thick sediment layers in the ice cover, and the latter uses two geophysical methods to quantify the extent and volume of the brine network in the subsurface beneath the lake. The results presented herein advance the study of hydrogeology in continuous permafrost, provide additional evidence for fluctuating climate states in the McMurdo Dry Valleys throughout the mid to late Holocene, and provide a case study for the preservation of water in a cold, desert environment analogous to neighboring planets.

10aAntarctica10abrine10alake ice10aMcMurdo Dry Valleys10apolar lakes10asublimation1 aDugan, Hilary, A.1 aDoran, Peter, T. uhttp://hdl.handle.net/10027/1940702874nas a2200133 4500008004100000245008500041210006900126260004000195490001000235520241400245100002202659700002102681856003802702 2014 eng d00aHydrological and Biogeochemical Modeling of Taylor Valley Lakes, East Antarctica0 aHydrological and Biogeochemical Modeling of Taylor Valley Lakes  aChicago, ILbUniversity of Illinois0 vPh.D.3 a

Taylor Valley, McMurdo Dry Valleys, East Antarctica contains three perennially ice-covered lakes located in closed basins. The lakes respond to climatic changes on seasonal and decadal scales due to their existence on a very narrow climatic spectrum. The climate has to be sufficiently warm during the austral summer to induce glacial melt yet cold enough to maintain the ice covers year round. This thesis is focused on better understanding and constraining the sensitivity of past and present lakes to changes in climatic forcings. Melt water generation for large proglacial lakes, that existed during the Last Glacial Maximum, is attributed to strong westerly winds that increase surface air temperature above freezing, prolonging the melt season. The high frequency of westerly winds during the Last Glacial Maximum, based on the ice core record from Taylor Dome, is responsible for generation of enough glacial melt to sustain large proglacial lakes during this time period, suggesting that summer surface air temperatures were as warm as present day. Contemporary lakes are much smaller, however, the effect of strong westerly winds on modern lakes is equally profound. Strong winds are responsible for aeolian sediment deposition on the surface of the ice covers. The deposited sediment, on the other hand, absorbs more solar radiation and preferentially decreases the ice thickness around it. The localized ice thinning allows a greater amount of light penetration into the water column, which is negatively correlated with chlorophyll-a concentration. This negative correlation does not indicate changes in biomass; rather, it is a result of the short-term photo-adaptation of phytoplankton to the light intensity by increasing/decreasing light harvesting antenna size. The ice thicknesses in Taylor Valley lakes have been fluctuating since the first measurements were obtained. A one-dimensional physics-based ice thickness model was developed capable of reproducing 16 years of ice thickness trends for two different lakes. The model is based on surface radiative fluxes while considering heat fluxes from the water column. Deep lakes with well-developed temperature maximum can facilitate or hinder ice thickness growth/decay due to the heat flux from the underlying water column. This finding suggests that not all perennially ice-covered lakes can be used as a proxy for climatic changes.

1 aObryk, Maciek, K.1 aDoran, Peter, T. uhttp://hdl.handle.net/10027/1890903712nas a2200157 4500008004100000245021300041210006900254260001200323300001600335490000800351520308500359100002203444700002103466700002103487856004603508 2014 eng d00aThe permanent ice cover of Lake Bonney, Antarctica: The influence of thickness and sediment distribution on photosynthetically available radiation and chlorophyll-a distribution in the underlying water column0 apermanent ice cover of Lake Bonney Antarctica The influence of t c09/2014 a1879 - 18910 v1193 a

The thick permanent ice cover on the lakes of the McMurdo Dry Valleys, Antarctica, inhibits spatial lake sampling due to logistical constraints of penetrating the ice cover. To date most sampling of these lakes has been made at only a few sites with the assumption that there is a spatial homogeneity of the physical and biogeochemical properties of the ice cover and the water column at any given depth. To test this underlying assumption, an autonomous underwater vehicle (AUV) was deployed in Lake Bonney, Taylor Valley. Measurements were obtained over the course of 2 years in a 100 × 100 m horizontal sampling grid (at a 0.2 m vertical resolution). Additionally, the AUV measured the ice thickness (in water equivalent) and collected images looking up through the ice, which were used to quantify sediment distribution on the surface and within the ice. Satellite imagery was used to map sediment distribution on the surface of the ice. We present results of the spatial investigation of the sediment distribution on the ice cover and its effects on biological processes, with particular emphasis on photosynthetically active radiation (PAR). The surface sediment is a secondary controller of the ice cover thickness, which in turn controls the depth-integrated PAR in the water column. Our data revealed that depth-integrated PAR was negatively correlated with depth-integrated chlorophyll-a (r = 0.88, p < 0.001, n = 83), which appears to be related to short-term photoadaptation of phytoplanktonic communities to spatial and temporal variation in PAR within the water column.

1 aObryk, Maciek, K.1 aDoran, Peter, T.1 aPriscu, John, C. uhttp://doi.wiley.com/10.1002/2014JG00267200623nas a2200169 4500008004100000245009600041210006900137260001200206300001200218490000700230100002100237700001800258700002100276700002200297700001700319856011700336 2014 eng d00aRadiocarbon abundance and reservoir effects in lakes of the McMurdo Dry Valleys, Antarctica0 aRadiocarbon abundance and reservoir effects in lakes of the McMu c05/2014 a811-8260 v591 aDoran, Peter, T.1 aKenig, Fabien1 aKnoepfle, Lawson1 aMikucki, Jill, A.1 aLyons, Berry uhttps://mcm.lternet.edu/content/radiocarbon-abundance-and-reservoir-effects-lakes-mcmurdo-dry-valleys-antarctica07866nas a2200205 4500008004100000022001400041245011200055210006900167260001200236300001400248490000700262520715200269100001907421700001907440700001807459700002707477700001807504700002107522856011707543 2013 eng d a1380-616500aCarbon Sequestration and Release from Antarctic Lakes: Lake Vida and West Lake Bonney (McMurdo Dry Valleys)0 aCarbon Sequestration and Release from Antarctic Lakes Lake Vida  c03/2013 a135 - 1450 v193 a

Perennial ice covers on many Antarctic lakes have resulted in high lake inorganic carbon contents. The objective of this paper was to evaluate and compare the brine and CO2 chemistries of Lake Vida (Victoria Valley) and West Lake Bonney (Taylor Valley), two lakes of the McMurdo Dry Valleys (East Antarctica), and their potential consequences during global warming. An existing geochemical model (FREZCHEM-15) was used to convert measured molarity into molality needed for the FREZCHEM model, and this model added a new algorithm that converts measured DIC into carbonate alkalinity needed for the FREZCHEM model. While quite extensive geochemical information exists for ice-covered Taylor Valley lakes, such as West Lake Bonney, only limited information exists for the recently sampled brine of >25 m ice-thick Lake Vida. Lake Vida brine had a model-calculated pCO2 = 0.60 bars at the field pH (6.20); West Lake Bonney had a model-calculated pCO2 = 5.23 bars at the field pH (5.46). Despite the high degree of atmospheric CO2supersaturation in West Lake Bonney, it remains significantly undersaturated with the gas hydrate, CO2·6H2O, unless these gas hydrates are deep in the sediment layer or are metastable having formed under colder temperatures or greater pressures. Because of lower temperatures, Lake Vida could start forming CO2·6H2O at lower pCO2 values than West Lake Bonney; but both lakes are significantly undersaturated with the gas hydrate, CO2·6H2O. For both lakes, simulation of global warming from current subzero temperatures (−13.4 °C in Lake Vida and −4.7 °C in West Lake Bonney) to 10 °C has shown that a major loss of solution-phase carbon as CO2 gases and carbonate minerals occurred when the temperatures rose above 0 °C and perennial ice covers would disappear. How important these Antarctic CO2 sources will be for future global warming remains to be seen. But a recent paper has shown that methane increased in atmospheric concentration due to deglaciation about 10,000 years ago. So, CO2 release from ice lakes might contribute to atmospheric gases in the future.

1 aMarion, G., M.1 aMurray, A., E.1 aWagner, Bernd1 aFritsen, Christian, H.1 aKenig, Fabien1 aDoran, Peter, T. uhttp://link.springer.com/10.1007/s10498-012-9184-1http://link.springer.com/content/pdf/10.1007/s10498-012-9184-100502nas a2200133 4500008004100000245007800041210006900119260000900188300001400197490000700211100002600218700002100244856010300265 2013 eng d00aDistribution of Siliceous-Walled Algae in Taylor Valley, Antarctica Lakes0 aDistribution of SiliceousWalled Algae in Taylor Valley Antarctic c2013 a688 - 6990 v041 aWarnock, Jonathan, P.1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/distribution-siliceous-walled-algae-taylor-valley-antarctica-lakes00501nas a2200133 4500008004100000245007300041210006900114260001200183490000700195100002200202700002200224700002100246856010000267 2013 eng d00aLake ice ablation rates from permanently ice-covered Antarctic lakes0 aLake ice ablation rates from permanently icecovered Antarctic la c01/20130 v591 aDugan, Hilary, A.1 aObryk, Maciek, K.1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/lake-ice-ablation-rates-permanently-ice-covered-antarctic-lakes00572nas a2200145 4500008004100000245015400041210006900195260001200264300001400276490000700290100001900297700002100316700001800337856007100355 2013 eng d00aMicro-hole and multigrain quartz luminescence dating of Paleodeltas at Lake Fryxell, McMurdo Dry Valleys (Antarctica), and relevance for lake history0 aMicrohole and multigrain quartz luminescence dating of Paleodelt c12/2013 a119 - 1340 v181 aBerger, G., W.1 aDoran, Peter, T.1 aThomsen, K.J. uhttp://www.sciencedirect.com/science/article/pii/S187110141300042300619nas a2200193 4500008004100000245006400041210005800105260001100163300001100174490000700185100001700192700002400209700002900233700001700262700002400279700001600303700002100319856008500340 2012 eng d00aThe geochemistry of upland ponds, Taylor Valley, Antarctica0 ageochemistry of upland ponds Taylor Valley Antarctica c2/2012 a3 - 140 v241 aLyons, Berry1 aWelch, Kathleen, A.1 aGardner, Christopher, B.1 aJaros, Chris1 aMoorhead, Daryl, L.1 aKnoepfle, J1 aDoran, Peter, T. uhttp://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=848335101017nas a2200337 4500008004100000022001400041245007500055210006900130260001200199300001800211490000800229100001900237700001800256700002700274700002700301700002300328700002000351700001900371700002400390700002500414700001700439700001800456700002100474700002700495700002400522700001800546700001900564700001900583700002100602856005600623 2012 eng d a0027-842400aMicrobial life at -13  C in the brine of an ice-sealed Antarctic lake0 aMicrobial life at 13 C in the brine of an icesealed Antarctic la c12/2012 a20626 - 206310 v1091 aMurray, A., E.1 aKenig, Fabien1 aFritsen, Christian, H.1 aMcKay, Christopher, P.1 aCawley, Kaelin, M.1 aEdwards, R., L.1 aKuhn, Emanuele1 aMcKnight, Diane, M.1 aOstrom, Nathaniel, E1 aPeng, Vivian1 aPonce, Adrian1 aPriscu, John, C.1 aSamarkin, Vladimir, A.1 aTownsend, Ashley, T1 aWagh, Protima1 aYoung, Seth, A1 aYung, Pung, To1 aDoran, Peter, T. uhttp://www.pnas.org/cgi/doi/10.1073/pnas.120860710901724nam a2200385 4500008004100000020002200041245011900063210006900182260005100251300001400302490000900316520052100325100002500846700002200871700001900893700002500912700002700937700002000964700002300984700002101007700002101028700001801049700001901067700001901086700001901105700002201124700001401146700002001160700002101180700002101201700002001222700001901242700001901261856005801280 2012 eng d a978-3-642-33179-400aPoisson Reconstruction of Extreme Submersed Environments: The ENDURANCE Exploration of an Under-Ice Antarctic Lake0 aPoisson Reconstruction of Extreme Submersed Environments The END aBerlin, HeidelbergbSpringer Berlin Heidelberg a394 - 4030 v74313 a

We evaluate the use of Poisson reconstruction to generate a 3D bathymetric model of West Lake Bonney, Antarctica. The source sonar dataset has been collected by the ENDURANCE autonomous ve- hicle in the course of two Antarctic summer missions. The reconstruction workflow involved processing 200 million datapoints to generate a high resolution model of the lake bottom, Narrows region and underwater glacier face. A novel and flexible toolset has been developed to automate the processing of the Bonney data.

1 aFebretti, Alessandro1 aRichmond, Kristof1 aGulati, Shilpa1 aFlesher, Christopher1 aHogan, Bartholomew, P.1 aJohnson, Andrew1 aStone, William, C.1 aPriscu, John, C.1 aDoran, Peter, T.1 aBebis, George1 aBoyle, Richard1 aParvin, Bahram1 aKoracin, Darko1 aFowlkes, Charless1 aWang, Sen1 aChoi, Min-Hyung1 aMantler, Stephan1 aSchulze, Jürgen1 aAcevedo, Daniel1 aMueller, Klaus1 aPapka, Michael uhttp://www.springerlink.com/content/hg97w43588229087/00571nas a2200157 4500008004100000245011700041210006900158260001200227300001400239490000700253100002600260700002600286700002200312700002100334856005800355 2011 eng d00aA diatom record of environmental change in Fryxell Basin, Taylor Valley, Antarctica, late Pleistocene to present0 adiatom record of environmental change in Fryxell Basin Taylor Va c08/2011 a257 - 2720 v461 aKonfirst, Matthew, A.1 aSjunneskog, Charlotte1 aScherer, Reed, P.1 aDoran, Peter, T. uhttp://www.springerlink.com/content/y3483576u8220081/00566nas a2200133 4500008004100000245008000041210006900121260006700190300001200257490000800269100002100277700002500298856010900323 2011 eng d00aEnvironmental Protection and Stewardship of Subglacial Aquatic Environments0 aEnvironmental Protection and Stewardship of Subglacial Aquatic E aBaltimorebAmerican Geophysical Union, Washington, DCc03/2011 a149-1570 v1921 aDoran, Peter, T.1 aVincent, Warwick, F. uhttps://mcm.lternet.edu/content/environmental-protection-and-stewardship-subglacial-aquatic-environments00641nas a2200181 4500008004100000245011500041210006900156260001100225300001400236490000700250100001800257700002100275700002100296700001800317700001900335700002000354856008500374 2011 eng d00aThe Holocene environmental history of Lake Hoare, Taylor Valley, Antarctica, reconstructed from sediment cores0 aHolocene environmental history of Lake Hoare Taylor Valley Antar c6/2011 a307 - 3190 v231 aWagner, Bernd1 aOrtlepp, Sabrina1 aDoran, Peter, T.1 aKenig, Fabien1 aMelles, Martin1 aBurkemper, Andy uhttp://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=827537400581nas a2200169 4500008004100000245008600041210006900127260001200196300001400208490000600222100002500228700002400253700002100277700002400298700001700322856007200339 2011 eng d00aHydrological Connectivity of the Landscape of the McMurdo Dry Valleys, Antarctica0 aHydrological Connectivity of the Landscape of the McMurdo Dry Va c09/2011 a666 - 6810 v51 aGooseff, Michael, N.1 aMcKnight, Diane, M.1 aDoran, Peter, T.1 aFountain, Andrew, G1 aLyons, Berry uhttp://onlinelibrary.wiley.com/doi/10.1111/j.1749-8198.2011.00445.x00722nas a2200193 4500008004100000020001800041245008800059210006900147260004200216300001400258100002500272700002400297700001700321700001700338700002100355700001700376700002400393856011100417 2010 eng d a978052188919300aAntarctic McMurdo Dry Valley stream ecosystems as analog to fluvial systems on Mars0 aAntarctic McMurdo Dry Valley stream ecosystems as analog to fluv aCambridgebCambridge University Press a139 - 1591 aGooseff, Michael, N.1 aMcKnight, Diane, M.1 aCarr, M., H.1 aBaeseman, J.1 aDoran, Peter, T.1 aLyons, Berry1 aMcKnight, Diane, M. uhttps://mcm.lternet.edu/content/antarctic-mcmurdo-dry-valley-stream-ecosystems-analog-fluvial-systems-mars00861nas a2200253 4500008004100000245013000041210006900171260001200240300001400252490000800266100001300274700002600287700001500313700001400328700002200342700001500364700001500379700001500394700001400409700001600423700002100439700002100460856012600481 2010 eng d00aDesign and deployment of a four-degrees-of-freedom hovering autonomous underwater vehicle for sub-ice exploration and mapping0 aDesign and deployment of a fourdegreesoffreedom hovering autonom c11/2010 a341 - 3610 v2241 aStone, W1 aHogan, Bartholomew, P1 aFlesher, C1 aGulati, S1 aRichmond, Kristof1 aMurarka, A1 aKuhlman, G1 aIdharan, M1 aSiegel, V1 aPrice, R, M1 aDoran, Peter, T.1 aPriscu, John, C. uhttps://mcm.lternet.edu/content/design-and-deployment-four-degrees-freedom-hovering-autonomous-underwater-vehicle-sub-ice00571nas a2200145 4500008004100000245009100041210006900132260001500201300001200216100001700228700002400245700002100269700002400290856011100314 2010 eng d00aA dynamic physical model for soil temperature and water in Taylor Valley, Antarctica.0 adynamic physical model for soil temperature and water in Taylor  c05/13/2010 a419-4341 aHunt, H., W.1 aFountain, Andrew, G1 aDoran, Peter, T.1 aBasagic, Hassan, J. uhttps://mcm.lternet.edu/content/dynamic-physical-model-soil-temperature-and-water-taylor-valley-antarctica00763nam a2200241 4500008004100000020001800041245005800059210005800117260004300175300000800218490000600226653002200232100002100254700001700275700002400292700002400316700002500340700003300365700002200398700002000420700001800440856006300458 2010 eng d a978051171225800aLife in Antarctic Deserts and Other Cold Environments0 aLife in Antarctic Deserts and Other Cold Environments aCambridgebCambridge University Press. a3070 v510aPlanetary Science1 aDoran, Peter, T.1 aLyons, Berry1 aMcKnight, Diane, M.1 aMcKnight, Diane, M.1 aGooseff, Michael, N.1 aTakacs-Vesbach, Cristina, D.1 aMikucki, Jill, A.1 aTranter, Martyn1 aSun, Henry, J uhttp://ebooks.cambridge.org/ebook.jsf?bid=CBO978051171225800662nas a2200181 4500008004100000245013300041210006900174260001200243300001400255490000800269100002400277700002200301700002000323700002100343700001800364700002700382856007100409 2010 eng d00aNew insights into the origin and evolution of Lake Vida, McMurdo Dry Valleys, Antarctica — A noble gas study in ice and brines0 aNew insights into the origin and evolution of Lake Vida McMurdo  c01/2010 a112 - 1220 v2891 aMalone, Jessica, L.1 aCastro, Clara, M.1 aHall, Chris, M.1 aDoran, Peter, T.1 aKenig, Fabien1 aMcKay, Christopher, P. uhttp://www.sciencedirect.com/science/article/pii/S0012821X0900633500684nas a2200169 4500008004100000245012300041210006900164260001100233300001400244490000700258100002800265700002400293700002900317700002100346700001800367856012900385 2010 eng d00aOrigin and tentative identification of tri to pentaunsaturated ketones in sediments from Lake Fryxell, East Antarctica0 aOrigin and tentative identification of tri to pentaunsaturated k c4/2010 a386 - 3970 v411 aJaraula, Caroline, M.B.1 aBrassell, Simon, C.1 aMorgan-Kiss, Rachael, M.1 aDoran, Peter, T.1 aKenig, Fabien uhttps://mcm.lternet.edu/content/origin-and-tentative-identification-tri-pentaunsaturated-ketones-sediments-lake-fryxell-east00643nas a2200169 4500008004100000245011300041210006900154260001200223300001400235490000700249100001800256700002100274700001800295700002100313700001900334856012000353 2010 eng d00aPalaeoenvironmental implications derived from a piston core from east lobe Bonney, Taylor Valley, Antarctica0 aPalaeoenvironmental implications derived from a piston core from c10/2010 a522 - 5300 v221 aWagner, Bernd1 aOrtlepp, Sabrina1 aKenig, Fabien1 aDoran, Peter, T.1 aMelles, Martin uhttps://mcm.lternet.edu/content/palaeoenvironmental-implications-derived-piston-core-east-lobe-bonney-taylor-valley00649nas a2200169 4500008004100000020001800041245010800059210006900167260004200236300001400278100002200292700001700314700001500331700002200346700002100368856009000389 2010 eng d a978052188919300aSaline lakes and ponds in the McMurdo Dry Valleys: ecological analogs to martian paleolake environments0 aSaline lakes and ponds in the McMurdo Dry Valleys ecological ana aCambridgebCambridge University Press a160 - 1941 aMikucki, Jill, A.1 aLyons, Berry1 aHawes, Ian1 aLanoil, Brian, D.1 aDoran, Peter, T. uhttp://ebooks.cambridge.org/chapter.jsf?bid=CBO9780511712258&cid=CBO9780511712258A01300598nas a2200145 4500008004100000245012800041210006900169260001200238300001400250490000600264100001900270700002100289700001800310856012400328 2010 eng d00aSingle-grain and multigrain luminescence dating of on-ice and lake-bottom deposits at Lake Hoare, Taylor Valley, Antarctica0 aSinglegrain and multigrain luminescence dating of onice and lake c12/2010 a679 - 6900 v51 aBerger, G., W.1 aDoran, Peter, T.1 aThomsen, K.J. uhttps://mcm.lternet.edu/content/single-grain-and-multigrain-luminescence-dating-ice-and-lake-bottom-deposits-lake-hoare00839nas a2200217 4500008004100000020002200041245013600063210007100199260003300270300001400303100001400317700002200331700001500353700002600368700001500394700002200409700002100431700001300452700002100465856013500486 2010 eng d a978-1-4244-5038-100aToward autonomous scientific exploration of ice-covered lakes—Field experiments with the ENDURANCE AUV in an Antarctic Dry Valley0 aToward autonomous scientific exploration of icecovered lakes—Fie aAnchorage, AKbIEEEc05/2010 a308 - 3151 aGulati, S1 aRichmond, Kristof1 aFlesher, C1 aHogan, Bartholomew, P1 aMurarka, A1 aKuhlmann, Gregory1 aSridharan, Mohan1 aStone, W1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/toward-autonomous-scientific-exploration-ice-covered-lakes%E2%80%94field-experiments-endurance-auv00627nas a2200157 4500008004100000245011700041210006900158300001400227490000700241100001500248700001800263700002100281700002100302700002400323856012200347 2009 eng d00aComposition and Biodegradation of a Synthetic Oil Spilled on the Perennial Ice Cover of Lake Fryxell, Antarctica0 aComposition and Biodegradation of a Synthetic Oil Spilled on the a2708-27130 v431 aJaraula, C1 aKenig, Fabien1 aDoran, Peter, T.1 aPriscu, John, C.1 aWelch, Kathleen, A. uhttps://mcm.lternet.edu/content/composition-and-biodegradation-synthetic-oil-spilled-perennial-ice-cover-lake-fryxell00419nas a2200133 4500008004100000245005700041210005700098260000900155300000700164490000700171100002100178700002600199856006000225 2009 eng d00aExamining the Scientific Consensus on Climate Change0 aExamining the Scientific Consensus on Climate Change c2009 a220 v901 aDoran, Peter, T.1 aZimmerman, Maggie, K. uhttp://www.agu.org/pubs/crossref/2009/2009EO030002.shtm00641nas a2200157 4500008004100000245014100041210006900182300001200251490000800263100001600271700002100287700001800308700001700326700001700343856012300360 2009 eng d00aParticulate organic and dissolved inorganic carbon stable isotopic compositions in Taylor Valley lakes, Antarctica: the effect of legacy0 aParticulate organic and dissolved inorganic carbon stable isotop a139-1560 v6321 aKnoepfle, J1 aDoran, Peter, T.1 aKenig, Fabien1 aLyons, Berry1 aGalchenko, V uhttps://mcm.lternet.edu/content/particulate-organic-and-dissolved-inorganic-carbon-stable-isotopic-compositions-taylor00514nas a2200133 4500008004100000245008400041210006900125260000900194300000800203490000700211100002100218700002600239856011500265 2009 eng d00aReply to Comments on “Examining the Scientific Consensus on Climate Change”0 aReply to Comments on Examining the Scientific Consensus on Clima c2009 a2330 v901 aDoran, Peter, T.1 aZimmerman, Maggie, K. uhttps://mcm.lternet.edu/content/reply-comments-%E2%80%9Cexamining-scientific-consensus-climate-change%E2%80%9D00639nas a2200169 4500008004100000245009800041210006900139300001200208490000600220100002100226700002700247700001900274700001800293700002700311700001200338856011900350 2008 eng d00aEntry approach into pristine ice-sealed lakes - Lake Vida, East Antarctica, a model ecosystem0 aEntry approach into pristine icesealed lakes Lake Vida East Anta a542-5470 v61 aDoran, Peter, T.1 aFritsen, Christian, H.1 aMurray, A., E.1 aKenig, Fabien1 aMcKay, Christopher, P.1 aKyne, J uhttps://mcm.lternet.edu/content/entry-approach-pristine-ice-sealed-lakes-lake-vida-east-antarctica-model-ecosystem00775nas a2200217 4500008004100000245010100041210006900142260001500211300001200226490000700238653002100245653001200266100002100278700002700299700002400326700002200350700002400372700001700396700002200413856012200435 2008 eng d00aHydrologic response to extreme warm and cold summers in the McMurdo Dry Valleys, East Antarctica0 aHydrologic response to extreme warm and cold summers in the McMu c05/16/2008 a499-5090 v2010aClimate Response10astreams1 aDoran, Peter, T.1 aMcKay, Christopher, P.1 aFountain, Andrew, G1 aNylen, Thomas, H.1 aMcKnight, Diane, M.1 aJaros, Chris1 aBarrett, John, E. uhttps://mcm.lternet.edu/content/hydrologic-response-extreme-warm-and-cold-summers-mcmurdo-dry-valleys-east-antarctica00528nas a2200145 4500008004100000245005900041210005900100260003600159100001500195700002100210700001700231700002500248700002800273856008100301 2008 eng d00aOrigin and geomorphology of lakes in the polar regions0 aOrigin and geomorphology of lakes in the polar regions aOxfordbOxford University Press1 aPienitz, R1 aDoran, Peter, T.1 aLamoureuz, S1 aVincent, Warwick, F.1 aLaybourn-Parry, Johanna uhttps://mcm.lternet.edu/content/origin-and-geomorphology-lakes-polar-regions00556nas a2200121 4500008004100000245011000041210006900151260003600220490000900256100002600265700002100291856012200312 2008 eng d00aProvenance of organic matter in Taylor Valley, Antarctica lakes: Scanning Electron Microscopy of sediment0 aProvenance of organic matter in Taylor Valley Antarctica lakes S bUniversity of Illinois, Chicago0 vM.S.1 aWarnock, Jonathan, P.1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/provenance-organic-matter-taylor-valley-antarctica-lakes-scanning-electron-microscopy00685nas a2200205 4500008004100000245010300041210006900144260000900213490000700222100002300229700002300252700002900275700001500304700002300319700002100342700001500363700001500378700002500393856006100418 2008 eng d00aReply to comment by K. Gajewski on “Abrupt environmental change in Canada's northernmost lake”0 aReply to comment by K Gajewski on Abrupt environmental change in c20080 v351 aAntoniades, Dermot1 aCrawley, Catherine1 aDouglas, Marianne, S. V.1 aPienitz, R1 aAndersen, Dale, T.1 aDoran, Peter, T.1 aHawes, Ian1 aPollard, W1 aVincent, Warwick, F. uhttp://www.agu.org/pubs/crossref/2008/2007GL032889.shtml00645nas a2200157 4500008004100000245012900041210006900170300001200239490000800251100001500259700001800274700002100292700002100313700002400334856012900358 2008 eng d00aSPME-GCMS study of the natural attenuation of aviation diesel spilled on the perennial ice cover of Lake Fryxell, Antarctica0 aSPMEGCMS study of the natural attenuation of aviation diesel spi a250-2620 v4071 aJaraula, C1 aKenig, Fabien1 aDoran, Peter, T.1 aPriscu, John, C.1 aWelch, Kathleen, A. uhttps://mcm.lternet.edu/content/spme-gcms-study-natural-attenuation-aviation-diesel-spilled-perennial-ice-cover-lake-fryxell03147nas a2200241 4500008004100000245006800041210006800109260001200177300001400189490000800203520239000211653001102601100002202612700002302634700001702657700002402674700002102698700002402719700002002743700002402763700002102787856009702808 2007 eng d00aBiogeochemical stoichiometry of Antarctic Dry Valley ecosystems0 aBiogeochemical stoichiometry of Antarctic Dry Valley ecosystems c02/2007 aG01010+120 v1123 a

Among aquatic and terrestrial landscapes of the McMurdo Dry Valleys, Antarctica, ecosystem stoichiometry ranges from values near the Redfield ratios for C:N:P to nutrient concentrations in proportions far above or below ratios necessary to support balanced microbial growth. This polar desert provides an opportunity to evaluate stoichiometric approaches to understand nutrient cycling in an ecosystem where biological diversity and activity are low, and controls over the movement and mass balances of nutrients operate over 10–106 years. The simple organisms (microbial and metazoan) comprising dry valley foodwebs adhere to strict biochemical requirements in the composition of their biomass, and when activated by availability of liquid water, they influence the chemical composition of their environment according to these ratios. Nitrogen and phosphorus varied significantly in terrestrial and aquatic ecosystems occurring on landscape surfaces across a wide range of exposure ages, indicating strong influences of landscape development and geochemistry on nutrient availability. Biota control the elemental ratio of stream waters, while geochemical stoichiometry (e.g., weathering, atmospheric deposition) evidently limits the distribution of soil invertebrates. We present a conceptual model describing transformations across dry valley landscapes facilitated by exchanges of liquid water and biotic processing of dissolved nutrients. We conclude that contemporary ecosystem stoichiometry of Antarctic Dry Valley soils, glaciers, streams, and lakes results from a combination of extant biological processes superimposed on a legacy of landscape processes and previous climates.

10aBiggie1 aBarrett, John, E.1 aVirginia, Ross, A.1 aLyons, Berry1 aMcKnight, Diane, M.1 aPriscu, John, C.1 aFountain, Andrew, G1 aWall, Diana, H.1 aMoorhead, Daryl, L.1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/biogeochemical-stoichiometry-antarctic-dry-valley-ecosystems00541nas a2200121 4500008004100000245010000041210006900141260003600210490000900246100002000255700002100275856012300296 2007 eng d00aLacustrine History of Lake Hoare, McMurdo Dry Valleys, Antarctica, Based on Long Sediment Cores0 aLacustrine History of Lake Hoare McMurdo Dry Valleys Antarctica  bUniversity of Illinois, Chicago0 vM.S.1 aBurkemper, Andy1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/lacustrine-history-lake-hoare-mcmurdo-dry-valleys-antarctica-based-long-sediment-cores00498nas a2200121 4500008004100000245007800041210006900119260003600188490000900224100002100233700002100254856010100275 2007 eng d00aStable Carbon Isotope Analyses of Sediments from Lake Fryxell, Antarctica0 aStable Carbon Isotope Analyses of Sediments from Lake Fryxell An bUniversity of Illinois, Chicago0 vM.S.1 aMoore-Topinka, N1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/stable-carbon-isotope-analyses-sediments-lake-fryxell-antarctica00704nas a2200169 4500008004100000245010300041210006900144260005400213100002500267700002400292700002100316700001700337700001700354700001900371700002700390856011700417 2007 eng d00aTrends in discharge and flow season timing of the Onyx River, Wright Valley, Antarctica since 19690 aTrends in discharge and flow season timing of the Onyx River Wri bU.S. Geological Survey Open-File Report 2007-10471 aGooseff, Michael, N.1 aMcKnight, Diane, M.1 aDoran, Peter, T.1 aLyons, Berry1 aCooper, Alan1 aRaymond, Carol1 aTeam, ISAES, Editorial uhttps://mcm.lternet.edu/content/trends-discharge-and-flow-season-timing-onyx-river-wright-valley-antarctica-196901738nas a2200229 4500008004100000245008300041210006900124260001200193300001100205490000700216520101800223653001101241100002501252700001201277700002401289700001101313700001301324700002501337700002101362700001601383856010901399 2006 eng d00aAntarctic Climate Cooling and Response of Diatoms in Glacial Meltwater Streams0 aAntarctic Climate Cooling and Response of Diatoms in Glacial Mel c04/2006 aL074060 v333 a

To understand biotic responses to an Antarctic cooling trend, we analyzed diatom samples from glacial meltwater streams in the McMurdo Dry Valleys, the largest ice-free area in Antarctica. Diatoms are abundant in these streams, and 24 of 40 species have only been found in the Antarctic. The percentage of these Antarctic diatom species increased with decreasing annual stream flow and increasing harshness of the stream habitat. The species diversity of assemblages reached a maximum when the Antarctic species accounted for 40–60% of relative diatom abundance. Decreased solar radiation and air-temperatures reduce annual stream flow, raising the dominance of these Antarctic species to levels above 60%. Thus, cooling favors the Antarctic species, and lowers diatom species diversity in this region.

10aBiggie1 aEsposito, Rhea, M.M.1 aHorn, S1 aMcKnight, Diane, M.1 aCox, M1 aGrant, M1 aSpaulding, Sarah, A.1 aDoran, Peter, T.1 aCozzetto, K uhttps://mcm.lternet.edu/content/antarctic-climate-cooling-and-response-diatoms-glacial-meltwater-streams00655nas a2200181 4500008004100000245011400041210006900155300000800224490000800232100001400240700001400254700002100268700001800289700001400307700001400321700001300335856012500348 2006 eng d00aGlacial and postglacial sedimentation in the Fryxell basin, Taylor Valley, Southern Victoria Land, Antarctica0 aGlacial and postglacial sedimentation in the Fryxell basin Taylo a3200 v3411 aWagner, B1 aMelles, M1 aDoran, Peter, T.1 aKenig, Fabien1 aForman, S1 aPierau, R1 aAllan, P uhttps://mcm.lternet.edu/content/glacial-and-postglacial-sedimentation-fryxell-basin-taylor-valley-southern-victoria-land00559nas a2200157 4500008004100000245008000041210006900121490000700190100001300197700001400210700001500224700001500239700002100254700001700275856010900292 2005 eng d00aBiogeological Raman spectroscopic studies of Antarctic lacustrine sediments0 aBiogeological Raman spectroscopic studies of Antarctic lacustrin0 v611 aMoody, C1 aVillar, S1 aEdwards, H1 aHodgson, D1 aDoran, Peter, T.1 aBishop, J.L. uhttps://mcm.lternet.edu/content/biogeological-raman-spectroscopic-studies-antarctic-lacustrine-sediments00884nas a2200265 4500008004100000245007800041210007000119300001100189490000700200653002500207100002100232700001900253700002700272700002700299700002400326700002100350700001700371700001300388700002400401700002400425700002400449700002300473700002000496856010200516 2005 eng d00aComment on ``El Niño suppresses Antarctic warming'' by N. Bertler et al.0 aComment on El Niño suppresses Antarctic warming by N Bertler et  aL077060 v3210aTropical meteorology1 aDoran, Peter, T.1 aClow, Gary, D.1 aFritsen, Christian, H.1 aMcKay, Christopher, P.1 aParsons, Andrew, N.1 aPriscu, John, C.1 aLyons, Berry1 aWalsh, J1 aFountain, Andrew, G1 aMcKnight, Diane, M.1 aMoorhead, Daryl, L.1 aVirginia, Ross, A.1 aWall, Diana, H. uhttps://mcm.lternet.edu/content/comment-el-ni%C3%B1o-suppresses-antarctic-warming-n-bertler-et-al00618nas a2200181 4500008004100000245006900041210006800110300000900178490000700187100001700194700002100211700002400232700001400256700002300270700002100293700002400314856009800338 2005 eng d00aDating water and solute additions to ice-covered Antarctic lakes0 aDating water and solute additions to icecovered Antarctic lakes aA7200 v691 aLyons, Berry1 aDowling, Carolyn1 aWelch, Kathleen, A.1 aSnyder, G1 aPoreda, Robert, J.1 aDoran, Peter, T.1 aFountain, Andrew, G uhttps://mcm.lternet.edu/content/dating-water-and-solute-additions-ice-covered-antarctic-lakes00711nas a2200205 4500008004100000245008900041210006900130300001200199490000700211100001700218700002400235700002000259700002000279700002300299700002400322700002100346700001400367700001500381856010900396 2005 eng d00aGroundwater seeps in Taylor Valley Antarctica: An example of a subsurface melt event0 aGroundwater seeps in Taylor Valley Antarctica An example of a su a200-2060 v401 aLyons, Berry1 aWelch, Kathleen, A.1 aCarey, Anne, E.1 aWall, Diana, H.1 aVirginia, Ross, A.1 aFountain, Andrew, G1 aDoran, Peter, T.1 aCsatho, B1 aTremper, C uhttps://mcm.lternet.edu/content/groundwater-seeps-taylor-valley-antarctica-example-subsurface-melt-event00443nas a2200121 4500008004100000245005800041210005800099260003600157490001000193100001400203700002100217856008300238 2005 eng d00aLacustrine Biogeochemistry of the McMurdo Dry Valleys0 aLacustrine Biogeochemistry of the McMurdo Dry Valleys bUniversity of Illinois, Chicago0 vPh.D.1 aLawson, J1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/lacustrine-biogeochemistry-mcmurdo-dry-valleys00662nas a2200193 4500008004100000245008500041210006900126260004000195300001200235100002700247700002300274700001500297700001600312700002100328700002700349700002100376700002000397856005100417 2005 eng d00aPolar lakes, streams, and springs as analogs for the hydrological cycle on Mars.0 aPolar lakes streams and springs as analogs for the hydrological  aBerlin, HeidelbergbSpringer Verlag a219-2331 aMcKay, Christopher, P.1 aAndersen, Dale, T.1 aPollard, W1 aHeldmann, J1 aDoran, Peter, T.1 aFritsen, Christian, H.1 aPriscu, John, C.1 aTokano, Tetsuya u/reports/lakes/McKayEtAl2005StreamsSprings.pdf00468nas a2200157 4500008004100000245002900041210002900070260003100099100001500130700002400145700002100169700001500190700002900205700001500234856006100249 2004 eng d00aAntarctic Paleolimnology0 aAntarctic Paleolimnology bKluwer Academic Publishers1 aHodgson, D1 aGibson, John, A. E.1 aDoran, Peter, T.1 aPienitz, R1 aDouglas, Marianne, S. V.1 aSmol, J.P. uhttps://mcm.lternet.edu/content/antarctic-paleolimnology00523nas a2200121 4500008004100000245009800041210006900139490000800208100002200216700002400238700002100262856011800283 2004 eng d00aClimatology of Katabatic Winds in the McMurdo Dry Valleys, Southern Victoria Land, Antarctica0 aClimatology of Katabatic Winds in the McMurdo Dry Valleys Southe0 v1091 aNylen, Thomas, H.1 aFountain, Andrew, G1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/climatology-katabatic-winds-mcmurdo-dry-valleys-southern-victoria-land-antarctica00594nas a2200193 4500008004100000245005000041210005000091260003100141100001200172700001400184700001300198700001400211700002100225700001600246700001500262700002900277700001500306856007900321 2004 eng d00aGeochronology of high latitude lake sediments0 aGeochronology of high latitude lake sediments bKluwer Academic Publishers1 aWolf, A1 aMiller, G1 aOlsen, C1 aForman, S1 aDoran, Peter, T.1 aHolmgren, S1 aPienitz, R1 aDouglas, Marianne, S. V.1 aSmol, J.P. uhttps://mcm.lternet.edu/content/geochronology-high-latitude-lake-sediments00791nas a2200217 4500008004100000020002200041245008200063210006900145260005900214300001200273100002100285700002100306700001700327700001400344700002300358700002300381700001500404700002900419700001500448856011000463 2004 eng d a978-1-4020-2125-100aPaleolimnology of extreme cold terrestrial and extraterrestrial environments.0 aPaleolimnology of extreme cold terrestrial and extraterrestrial  aDordrecht, The NetherlandsbKluwer Academic Publishers a475-5071 aDoran, Peter, T.1 aPriscu, John, C.1 aLyons, Berry1 aPowell, R1 aPoreda, Robert, J.1 aAndersen, Dale, T.1 aPienitz, R1 aDouglas, Marianne, S. V.1 aSmol, J.P. uhttps://mcm.lternet.edu/content/paleolimnology-extreme-cold-terrestrial-and-extraterrestrial-environments00602nas a2200193 4500008004100000245004700041210004600088260003100134300001200165100002100177700002100198700001700219700001400236700002300250700001500273700002900288700001500317856007600332 2004 eng d00aPaleolimnology of Ice-covered Environments0 aPaleolimnology of Icecovered Environments bKluwer Academic Publishers a475-5071 aDoran, Peter, T.1 aPriscu, John, C.1 aLyons, Berry1 aPowell, R1 aPoreda, Robert, J.1 aPienitz, R1 aDouglas, Marianne, S. V.1 aSmol, John uhttps://mcm.lternet.edu/content/paleolimnology-ice-covered-environments00661nas a2200157 4500008004100000245015000041210006900191300001200260490000700272100001400279700002100293700001800314700002500332700002100357856012500378 2004 eng d00aStable carbon and nitrogen isotopic compositions of benthic and pelagic organic matter in four polar lakes of the McMurdo Dry Valleys, Antarctica0 aStable carbon and nitrogen isotopic compositions of benthic and  a269-3010 v101 aLawson, J1 aDoran, Peter, T.1 aKenig, Fabien1 aDesMarais, David, J.1 aPriscu, John, C. uhttps://mcm.lternet.edu/content/stable-carbon-and-nitrogen-isotopic-compositions-benthic-and-pelagic-organic-matter-four00482nas a2200121 4500008004100000245007500041210006900116260003600185490000900221100001300230700002100243856009600264 2003 eng d00aDistribution of 210Pb and 137Cs in the McMurdo Dry Valleys, Antarctica0 aDistribution of 210Pb and 137Cs in the McMurdo Dry Valleys Antar bUniversity of Illinois, Chicago0 vM.S.1 aOlsen, C1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/distribution-210pb-and-137cs-mcmurdo-dry-valleys-antarctica00567nas a2200169 4500008004100000245009200041210006900133260001200202300001000214490000800224100002100232700002700253700002700280700002100307700002200328856004700350 2003 eng d00aFormation and character of an ancient 19 m ice cover and underlying trapped brine in an0 aFormation and character of an ancient 19 m ice cover and underly c01/2003 a26-310 v1001 aDoran, Peter, T.1 aFritsen, Christian, H.1 aMcKay, Christopher, P.1 aPriscu, John, C.1 aAdams, Edward, E. uhttp://www.pnas.org/content/100/1/26.short00733nas a2200193 4500008004100000245014900041210006900190300001200259490000600271100001500277700002100292700001900313700001400332700001400346700001900360700001500379700002100394856012400415 2003 eng d00aFourier-transform raman spectroscopic studies of organic and inorganic chemical components in stromatolitic cores from Antarctic lake sediments0 aFouriertransform raman spectroscopic studies of organic and inor a325-3310 v11 aEdwards, H1 aWynn-Williams, D1 aEllis-Evans, J1 aNewton, E1 aLittle, S1 ade Oliveira, L1 aHodgson, D1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/fourier-transform-raman-spectroscopic-studies-organic-and-inorganic-chemical-components00890nas a2200277 4500008004100000245006500041210006500106260001200171300001200183490000800195653002100203100002100224700002100245700001700266700002000283700002400303700002400327700002400351700002300375700002000398700001900418700002700437700002700464700002400491856009700515 2002 eng d00aAntarctic climate cooling and terrestrial ecosystem response0 aAntarctic climate cooling and terrestrial ecosystem response c01/2002 a517-5200 v41510aClimate Response1 aDoran, Peter, T.1 aPriscu, John, C.1 aLyons, Berry1 aWalsh, John, E.1 aFountain, Andrew, G1 aMcKnight, Diane, M.1 aMoorhead, Daryl, L.1 aVirginia, Ross, A.1 aWall, Diana, H.1 aClow, Gary, D.1 aFritsen, Christian, H.1 aMcKay, Christopher, P.1 aParsons, Andrew, N. uhttps://mcm.lternet.edu/content/antarctic-climate-cooling-and-terrestrial-ecosystem-response00772nas a2200253 4500008004100000245004700041210004700088300001200135490000800147100002000155700001900175700002700194700002700221700002400248700002100272700002100293700001700314700002400331700002400355700002400379700002300403700002000426856007200446 2002 eng d00aRecent Temperature Trends in the Antarctic0 aRecent Temperature Trends in the Antarctic a291-2920 v4181 aWalsh, John, E.1 aClow, Gary, D.1 aFritsen, Christian, H.1 aMcKay, Christopher, P.1 aParsons, Andrew, N.1 aDoran, Peter, T.1 aPriscu, John, C.1 aLyons, Berry1 aFountain, Andrew, G1 aMcKnight, Diane, M.1 aMoorhead, Daryl, L.1 aVirginia, Ross, A.1 aWall, Diana, H. uhttps://mcm.lternet.edu/content/recent-temperature-trends-antarctic00760nas a2200229 4500008004100000245012700041210006900168260001200237300001000249490000700259653001100266100002500277700002200302700002100324700002400345700001700369700002400386700001800410700002300428700002000451856005900471 2002 eng d00aSnow patch influence on soil biogeochemical processes and invertebrate distribution in the McMurdo Dry Valleys, Antarctica0 aSnow patch influence on soil biogeochemical processes and invert c02/2003 a91-990 v3510aBiggie1 aGooseff, Michael, N.1 aBarrett, John, E.1 aDoran, Peter, T.1 aFountain, Andrew, G1 aLyons, Berry1 aParsons, Andrew, N.1 aPorazinska, D1 aVirginia, Ross, A.1 aWall, Diana, H. uhttp://instaar.metapress.com/content/r086455ju7213711/03551nas a2200217 4500008004100000245009000041210006900131260001200200300001400212490000800226520282700234653001103061100002103072700002703093700001903120700002003139700002403159700002203183700001703205856011103222 2002 eng d00aValley floor climate observations from the McMurdo Dry Valleys, Antarctica, 1986-20000 aValley floor climate observations from the McMurdo Dry Valleys A c12/2002 a4772-47840 v1073 a

Climate observations from the McMurdo dry valleys, East Antarctica are presented from a network of seven valley floor automatic meteorological stations during the period 1986 to 2000. Mean annual temperatures ranged from −14.8°C to −30.0°C, depending on the site and period of measurement. Mean annual relative humidity is generally highest near the coast. Mean annual wind speed increases with proximity to the polar plateau. Site-to-site variation in mean annual solar flux and PAR is due to exposure of each station and changes over time are likely related to changes in cloudiness. During the nonsummer months, strong katabatic winds are frequent at some sites and infrequent at others, creating large variation in mean annual temperature owing to the warming effect of the winds. Katabatic wind exposure appears to be controlled to a large degree by the presence of colder air in the region that collects at low points and keeps the warm less dense katabatic flow from the ground. The strong influence of katabatic winds makes prediction of relative mean annual temperature based on geographical position (elevation and distance from the coast) alone, not possible. During the summer months, onshore winds dominate and warm as they progress through the valleys creating a strong linear relationship (r2 = 0.992) of increasing potential temperature with distance from the coast (0.09°C km−1). In contrast to mean annual temperature, summer temperature lends itself quite well to model predictions, and is used to construct a statistical model for predicting summer dry valley temperatures at unmonitored sites.

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review.0 aMcMurdo Dry Valleys LongTerm Ecological Research Program new und a202-2170 v251 aLyons, Berry1 aWelch, Kathleen, A.1 aPriscu, John, C.1 aLaybourn-Parry, Johanna1 aMoorhead, Daryl, L.1 aMcKnight, Diane, M.1 aDoran, Peter, T.1 aTranter, Martyn uhttps://mcm.lternet.edu/content/mcmurdo-dry-valleys-long-term-ecological-research-program-new-understanding-biogeochemistry00770nas a2200193 4500008004100000245019000041210006900231300001400300490000700314100002300321700001500344700001400359700002100373700001600394700001300410700001500423700001700438856012100455 2001 eng d00aMineralogical and geochemical analyses of Antarctic lake sediments: A study of reflectanceand Mossbauer spectroscopy and C, N and S isotopes with applications for remote sensing on Mars0 aMineralogical and geochemical analyses of Antarctic lake sedimen a2875-28970 v651 aBishop, Janice, L.1 aLougear, A1 aNewton, J1 aDoran, Peter, T.1 aFroeschl, H1 aKrner, W1 aKoeberl, C1 aTrautwein, A uhttps://mcm.lternet.edu/content/mineralogical-and-geochemical-analyses-antarctic-lake-sediments-study-reflectanceand00706nas a2200169 4500008004100000245014800041210006900189300001000258490000700268100002400275700002500299700002500324700002100349700001800370700002300388856012500411 2001 eng d00aSpectrofluorometric characterization of aquatic fulvic acid for determination of precursor organic material and general structural properties.0 aSpectrofluorometric characterization of aquatic fulvic acid for  a38-480 v461 aMcKnight, Diane, M.1 aBoyer, Elizabeth, W.1 aWesterhoff, Paul, K.1 aDoran, Peter, T.1 aKulbe, Thomas1 aAndersen, Dale, T. uhttps://mcm.lternet.edu/content/spectrofluorometric-characterization-aquatic-fulvic-acid-determination-precursor-organic00868nas a2200229 4500008004100000245013400041210006900175260002800244300001200272100002400284700001700308700002400325700001700349700002400366700002200390700002100412700002700433700001800460700001900478700001800497856012300515 2000 eng 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aNezat, C., A.1 aWelch, Kathleen, A.1 aKottmeier, S1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/fossil-fuel-burning-taylor-valley-southern-victoria-land-antarctica-estimating-role00667nas a2200169 4500008004100000245011600041210006900157300001200226490000700238100001700245700002400262700002100286700002100307700001900328700002400347856012600371 2000 eng d00aThe importance of landscape position and legacy: The evolution of the Taylor Valley Lake District, Antarctica.0 aimportance of landscape position and legacy The evolution of the a355-3670 v431 aLyons, Berry1 aFountain, Andrew, G1 aDoran, Peter, T.1 aPriscu, John, C.1 aNeumann, Klaus1 aWelch, Kathleen, A. uhttps://mcm.lternet.edu/content/importance-landscape-position-and-legacy-evolution-taylor-valley-lake-district-antarctica00522nas a2200157 4500008004100000245005500041210005300096260003100149300001000180653001100190100002100201700001700222700001800239700002200257856008500279 1999 eng d00aArctic and Antarctic lakes: contrast or continuum?0 aArctic and Antarctic lakes contrast or continuum bUniversity of Ottawa Press a59-6810aBiggie1 aDoran, Peter, T.1 aAdams, Peter1 aEcclestone, M1 aLewkowicz, A., G. uhttps://mcm.lternet.edu/content/arctic-and-antarctic-lakes-contrast-or-continuum00684nas a2200205 4500008004100000245008100041210006900122260001200191300001200203490000800215653001400223100002100237700001900258700001700277700002400294700002100318700001600339700001700355856010600372 1999 eng d00aDating quaternary lacustrine sediments in the McMurdo Dry Valleys Antarctica0 aDating quaternary lacustrine sediments in the McMurdo Dry Valley c03/1999 a223-2390 v14710asediments1 aDoran, Peter, T.1 aBerger, G., W.1 aLyons, Berry1 aWharton, Robert, A.1 aDavisson, M., L.1 aSouthon, J.1 aDibb, J., E. uhttps://mcm.lternet.edu/content/dating-quaternary-lacustrine-sediments-mcmurdo-dry-valleys-antarctica00521nas a2200145 4500008004100000245006200041210006200103100001700165700001600182700002400198700002100222700002300243700002300266856008600289 1999 eng d00aEffects of research diving on a stratified antarctic lake0 aEffects of research diving on a stratified antarctic lake1 aKepner, R.L.1 aKortyna, A.1 aWharton, Robert, A.1 aDoran, Peter, T.1 aAndersen, Dale, T.1 aRoberts, Emily, C. uhttps://mcm.lternet.edu/content/effects-research-diving-stratified-antarctic-lake00514nas a2200109 4500008004100000245006200041210006000103260010700163100002400270700002100294856008900315 1999 eng d00aMcMurdo Dry Valley Lakes: Impacts of Research Activities.0 aMcMurdo Dry Valley Lakes Impacts of Research Activities bDesert Research Institute, University and Community College System of Nevada, USA, special publication1 aWharton, Robert, A.1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/mcmurdo-dry-valley-lakes-impacts-research-activities00878nas a2200277 4500008004100000245006500041210006400106260001200170300001200182490000700194653002300201100002400224700001700248700002400265700002000289700002100309700002100330700002400351700002400375700002400399700002100423700002000444700002400464700002300488856008900511 1999 eng d00aPhysical controls on the Taylor Valley Ecosystem, Antarctica0 aPhysical controls on the Taylor Valley Ecosystem Antarctica c12/1999 a961-9720 v4910aWater availability1 aFountain, Andrew, G1 aLyons, Berry1 aBurkins, Melody, B.1 aDana, Gayle, L.1 aDoran, Peter, T.1 aLewis, Karen, J.1 aMcKnight, Diane, M.1 aMoorhead, Daryl, L.1 aParsons, Andrew, N.1 aPriscu, John, C.1 aWall, Diana, H.1 aWharton, Robert, A.1 aVirginia, Ross, A. uhttps://mcm.lternet.edu/content/physical-controls-taylor-valley-ecosystem-antarctica00570nas a2200157 4500008004100000245007400041210006900115260001200184300001600196490000800212100002100220700002400241700002500265700002700290856009500317 1998 eng d00aAntarctic paleolake sediments and the search for extinct life on Mars0 aAntarctic paleolake sediments and the search for extinct life on c05/1998 a28481-284930 v1031 aDoran, Peter, T.1 aWharton, Robert, A.1 aDesMarais, David, J.1 aMcKay, Christopher, P. uhttps://mcm.lternet.edu/content/antarctic-paleolake-sediments-and-search-extinct-life-mars00605nas a2200169 4500008004100000245008000041210006900121300001200190490000700202100002100209700002000230700001900250700002200269700002100291700001700312856010600329 1998 eng d00aEvidence of deep circulation in two perennially ice-covered Antarctic lakes0 aEvidence of deep circulation in two perennially icecovered Antar a625-6350 v431 aTyler, Scott, W.1 aCook, Peter, G.1 aButt, Anya, Z.1 aThomas, James, M.1 aDoran, Peter, T.1 aLyons, Berry uhttps://mcm.lternet.edu/content/evidence-deep-circulation-two-perennially-ice-covered-antarctic-lakes00591nas a2200145 4500008004100000245010800041210006900149260001200218300001200230490000700242100002100249700002400270700002400294856012700318 1998 eng d00aMcMurdo Dry Valleys LTER: Geophysical determination of bathymetry and morphology of Taylor Valley lakes0 aMcMurdo Dry Valleys LTER Geophysical determination of bathymetry c01/1996 a198-2000 v311 aDoran, Peter, T.1 aWharton, Robert, A.1 aSchmok, Jeffrey, P. uhttps://mcm.lternet.edu/content/mcmurdo-dry-valleys-lter-geophysical-determination-bathymetry-and-morphology-taylor-valley00762nas a2200241 4500008004100000245007100041210006900112260001200181300001400193490000800207653001100215100002100226700002700247700002200274700002800296700002000324700002700344700002100371700002400392700002200416700002400438856005800462 1998 eng d00aPerennial Antarctic Lake Ice: An Oasis for Life in a Polar Desert0 aPerennial Antarctic Lake Ice An Oasis for Life in a Polar Desert c06/1998 a2095-20980 v28010aBiggie1 aPriscu, John, C.1 aFritsen, Christian, H.1 aAdams, Edward, E.1 aGiovannoni, Stephen, J.1 aPaerl, Hans, W.1 aMcKay, Christopher, P.1 aDoran, Peter, T.1 aGordon, Douglas, A.1 aLanoil, Brian, D.1 aPinckney, James, L. uhttp://www.sciencemag.org/content/280/5372/2095.short00670nas a2200181 4500008004100000245009200041210006900133260002900202300001200231100001700243700002200260700002300282700002100305700001700326700002700343700001500370856010300385 1997 eng d00aClimate history of the McMurdo Dry Valleys since the last glacial maximum: A synthesis0 aClimate history of the McMurdo Dry Valleys since the last glacia bBalkema Press, Rotterdam a155-1621 aLyons, Berry1 aBartek, Louis, R.1 aMayewski, Paul, A.1 aDoran, Peter, T.1 aLyons, Berry1 aHoward-Williams, Clive1 aHawes, Ian uhttps://mcm.lternet.edu/content/climate-history-mcmurdo-dry-valleys-last-glacial-maximum-synthesis00640nas a2200145 4500008004100000245015200041210006900193300001200262490000700274100002500281700002400306700001900330700002100349856012400370 1997 eng d00aDiatoms in sediments of perennially ice-covered Lake Hoare, and implications for interpreting lake history in the McMurdo Dry Valleys of Antarctica0 aDiatoms in sediments of perennially icecovered Lake Hoare and im a403-4200 v171 aSpaulding, Sarah, A.1 aMcKnight, Diane, M.1 aStoermer, E.F.1 aDoran, Peter, T. uhttps://mcm.lternet.edu/content/diatoms-sediments-perennially-ice-covered-lake-hoare-and-implications-interpreting-lake00487nas a2200121 4500008004100000245006700041210006600108260004000174490001000214100002100224700002400245856009600269 1996 eng d00aPaleolimnology of Perenially Ice-Covered Antarctic Oasis Lakes0 aPaleolimnology of Perenially IceCovered Antarctic Oasis Lakes aReno, NVbUniversity of Nevada Reno0 vPh.D.1 aDoran, Peter, T.1 aWharton, Robert, A. uhttps://mcm.lternet.edu/content/paleolimnology-perenially-ice-covered-antarctic-oasis-lakes00378nas a2200109 4500008004100000245005700041210005400098300000600152490000600158100002100164856008300185 1996 eng d00aA weather network in McMurdo Dry Valleys, Antarctica0 aweather network in McMurdo Dry Valleys Antarctica a30 v71 aDoran, Peter, T. 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