limndic.dat English utf8 dataset McMurdo Dry Valleys LTER Information Manager im@mcmlter.org pointOfContact 2014-11-04 ISO 19115-2 Geographic Information - North American Profile Metadata - Data with Biological Extensions ISO 19115-2:2009(E) Dissolved inorganic carbon (DIC) concentrations in discrete water column samples collected from lakes in the McMurdo Dry Valleys, Antarctica (1993-2022, ongoing) 2014-11-04 publication John Priscu Montana State University http://www.montana.edu/ jpriscu@montana.edu pointOfContact documentDigital The McMurdo Long Term Ecological Research (LTER) project monitors patterns of inorganic material transport in perennial ice-capped lakes. This data set addresses this core area of research and quantifies dissolved inorganic carbon concentrations at specific depths in McMurdo Dry Valley lakes. Dissolved inorganic carbon is also necessary for the computation of primary productivity. Name: Jade Lawrence Role: field technician Name: Kathleen A. Welch Role: lab technician Name: Renée F. Brown Role: data manager Name: Amy Chiuchiolo Role: former field crew Name: Inigo San Gil Role: former data manager completed McMurdo Dry Valleys LTER Information Manager im@mcmlter.org pointOfContact unknown 2015 - data and metadata managed now using the Drupal Ecological Information Management System    Data from this table was submitted to INSTAAR by John Priscu's team at Montana State University. The raw data files listed under 'file name' are the names of the original  files submitted. The 1993/94 and 1994/95 datasets are Microsoft Excel version 6.0 files, and the 1995/96, 1996/97 and 1997/98 datasets are ascii text files. Upon arrival at INSTAAR, the data manager fine-tuned the location codes and limno runs to match those provided in the "locations, dates, codes for lake chemistry, biology samples" file. The file was imported into Microsoft Access on INSTAAR's Unix system, and can currently be found there. The file was then exported in ascii, comma delimited text and MS-DOS text (table layout) to present on the MCM LTER web site. Both of these files are linked to this web page above. Information for the metadata was obtained from the Metadic9697.rtf file. The file was called up using Microsoft Word version 6.0. Text from this file was used to create this page in html format. inorganic nutrients theme LTER Core Areas English Lake Bonney is a saline lake with permanent ice cover at the western end of Taylor Valley in the McMurdo Dry Valleys of Victoria Land, Antarctica. It is 7 kilometres or 4.3 mi long and up to 900 metres or 3,000 ft wide. A narrow channel only 50 metres or 160 ft wide. Lake Bonney at Narrows separates the lake into East Lake Bonney 3.32 square kilometres or 1.28 sq mi and West Lake Bonney, 0.99 square kilometres or 0.38 sq mi. The west lobe is flanked by Taylor glacier. Valley: Taylor Distance to Sea : 25 Maximum Length (km): 4.8 Maximum Width (km): 0.9 Maximum Depth (m): 37 Surface Area (km^2): 3.32 Ice Thickness Average Surface (m): 3 - 4.5 Volume (m^3 * 10^6): 54.7 162.536209106445 162.353210449219 -77.724441528320 -77.697700500488 Lake Brownworth is a meltwater lake west of Wright Lower Glacier at the east end of Wright Valley. It was named by the Advisory Committee on Antarctic Names for Frederick S. Brownworth Jr., 162.823226928711 162.718856811523 -77.442016601563 -77.417655944824 Narrows between Lake Chad and Lake Hoare is a short spillway approximately 5m long between Lake Chad and Lake Hoare. Wharton, House and McKay streams flow into Lake Chad from the Suess Glacier. The overflow from Lake Chad then flows into the west end of Lake Hoare. There are many microbial mats in this area between the Hoare and Chad moats and around the spillway. Valley: Taylor Distance to Sea : 24 Maximum Length (km): 0.005 162.793258666992 162.774902343750 -77.641983032227 -77.639038085938 The Lake Fryxell basin is formed by a moraine depression in a wider portion of the Taylor Valley. It has a number of moraine islands and shallower areas, as well as several relatively well developed deltas. The lake is fed by at least 10 meltwater streams with a total drainage catchment of 230 km2. The lake is dammed to the southwest by the Canada Glacier and is topographically closed. It is perennially ice covered; during summer months, an ice-free moat generally forms around much of the lake margin. Lake levels have risen ~2 m between 1971 and 1996. There are no surface outflows; the only known water loss is through ice ablation (evaporation, sublimation and physical scouring). Valley: Taylor Distance to Sea : 9 Maximum Length (km): 5.8 Maximum Width (km): 2.1 Maximum Depth (m): 20 Surface Area (km^2): 7.08 Ice Thickness Average Surface (m): 3.3 - 4.5 Volume (m^3 * 10^6): 25.2 163.259582519531 163.048782348633 -77.622711181641 -77.597076416016 Lake Garwood is located in the Garwood Valley, adjacent to McMurdo Sound on the east side. It is fed by the Garwood River, which contains meltwater from Garwood Glacier, as well as Joyce Glacier, which melts into Lake Colleen, which in turn flows into the Garwood River. Valley: Garwood Distance to Sea : 0.01 164.310836791992 164.276672363281 -78.034614562988 -78.030540466309 Lake Hoare occupies a narrower portion of the Taylor Valley, dammed by the Canada Glacier. It would drain almost completely without this dam. There are a number of islands which may be related to an old terminal of Canada Glacier. The lake is fed primarily from direct runoff from the glacier, as well as meltwater streams. (Lake level rose ~1.5 m between 1972 and 1996). There are no surface outflows; the only known water loss is through ice ablation (evaporation, sublimation and physical scouring). Valley: Taylor Distance to Sea : 15 Maximum Length (km): 4.2 Maximum Width (km): 1 Maximum Depth (m): 34 Surface Area (km^2): 1.94 Ice Thickness Average Surface (m): 3.1 - 5.5 Volume (m^3 * 10^6): 17.5 162.935836791992 162.784423828125 -77.639259338379 -77.623085021973 Lake Joyce lies in the Pearse Valley against the Taylor Glacier.  Valley: Pearse  Distance to Sea : 44  Maximum Length (km): 1  Maximum Width (km): 1  Maximum Depth (m): 35  Surface Area (km^2): 0.83  Ice Thickness Average Surface (m): 3.9 - 5.6  Volume (m^3 * 10^6): 4.9 161.662445068359 161.608886718750 -77.726486206055 -77.715972900391 Lake Miers lies in the Miers Valley. Valley: Miers Distance to Sea : 20 Maximum Length (km): 1.5 Maximum Width (km): 0.7 Maximum Depth (m): 21 Surface Area (km^2): 1.3 Ice Thickness Average Surface (m): 3.4 - 6 Volume (m^3 * 10^6): 2.9 163.886840820313 163.812332153320 -78.101478576660 -78.094047546387 A lake with an area of 1 square mile which occupies the north portion of Pyramid Trough, Scott Coast. Named by New Zealand Geographic Board (NZGB) (1994) in association with Pyramid Trough. 162.823226928711 162.718856811523 -77.442016601563 -77.417655944824 Lake Vanda is located in the Wright Valley, adjacent to the Taylor Valley. It is fed primarily by the Onyx River, which has its origin at Lake Brownworth, and ultimately at the Lower Wright Glacier located ~27 km east of the lake. The lake has no outflow. Valley: Wright Distance to Sea : 47 Maximum Length (km): 8 Maximum Width (km): 2 Maximum Depth (m): 75 Surface Area (km^2): 5.2 Ice Thickness Average Surface (m): 2.8 - 4.2 Volume (m^3 * 10^6): 160 161.691970825195 161.391906738281 -77.542304992676 -77.518882751465 Lake Bonney is a saline lake with permanent ice cover at the western end of Taylor Valley in the McMurdo Dry Valleys of Victoria Land, Antarctica. It is 7 kilometres or 4.3 mi long and up to 900 metres or 3,000 ft wide. A narrow channel only 50 metres or 160 ft wide. Lake Bonney at Narrows separates the lake into East Lake Bonney 3.32 square kilometres or 1.28 sq mi and West Lake Bonney, 0.99 square kilometres or 0.38 sq mi. Valley: Taylor Distance to Sea : 28 Maximum Length (km): 2.6 Maximum Width (km): 0.9 Maximum Depth (m): 40 Surface Area (km^2): 0.99 Ice Thickness Average Surface (m): 2.8-4.5 Volume (m^3 * 10^6): 10.1 162.354934692383 162.269104003906 -77.727287292480 -77.714805603027 ground condition 1993-10-27 2022-12-22 Data contained in these files has been subjected to quality control standards imposed by the investigator. The user of this data should be aware that, while efforts have been taken to ensure that these data are of the highest quality, there is no guarantee of perfection for the data contained herein and the possibility of errors exists. If you encounter questionable data, please contact the MCM LTER data manager corrected or qualified. Thus, these data may be modified and future data will be appended. https://mcm.lternet.edu/sites/default/files/data/mcmlter-lake-dic-20230711.csv LIMNO_DIC eng; US McMurdo Dry Valleys LTER LIMNO_DIC Data Source Definition : Dissolved Organic Carbon data Record Delimiter : \n Number of Header Lines : 1 Number of Footer Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false DATASET_CODE Code to designate the table name LIMNO_RUN Code for lake's sampling location and date Location Name Name of lake where measurement was made Location Code Code for site where measurement was made DATE_TIME Date on which sample was gathered Date Time Format: mm/dd/yyyy Depth (m) Distance below the piezometric water level from which sample was drawn. DIC (mg C/l) Dissolved inorganic carbon concentration found at lake depth - mass units DIC (mM) Dissolved inorganic carbon concentration found at lake depth - moles DIC Comments Helpful hints about the DIC sample File Name Name of file in which data was submitted DEPTH MASL Depth referred to the Sea level. Distance below Mean Average Sea water level reference from which sample was drawn DBF https://mcm.lternet.edu/sites/default/files/data/mcmlter-lake-dic-20230711.csv dataset General Methodology Lake water samples are collected at specific depths with a five-liter Niskin bottle during normal LTER limnological sampling. Dissolved inorganic carbon samples (1 at each depth) are decanted through tubing directly from the Niskin bottle into a 30 mL serum vial. Lake water is allowed to overflow from the serum vial and completely displace the initial sample volume. Each sample is preserved with 0.15 mL chloroform, capped with a rubber stopper and crimped with an aluminum cap. Samples are stored in the dark at 4 degrees C until analysis. Samples are analyzed in at least duplicate following a method of sample acidification followed by infrared gas analysis using an IRGA (Infrared Gas Analyzer), and comparison to a standard curve. The standard curve is created by analyzing incremental samples of a 60 mgC/L DIC standard. The reported dissolved inorganic carbon concentrations of the lake water samples are averages of the replicate sample analyses. Analyses were performed with either an MSA Lira IRGA with HP Integrator or a Licor 6252 CO2 analyzer prior to the 2003-2004 season, with an MSA Lira IRGA with HP Integrator or Peak Simple Chromatography Data System from the 2003-2004 – 2006-2007 season, and with a Qubit Systems Infrared CO2 Analyzer with Peak Simple Chromatography Data System from the 2007-2008 season to present. Notes on 2006-2007 Season DIC Data and methods The IRGA malfunctioned during the 0607 season yielding DIC data that were highly suspect. Alkalinity titrations were done according to standard methods and DIC was estimated based on Wetzel R.G. and G.E. Likens. 1991. Limnological Analyses. 2nd Edition. Springer-Verlag New York Inc. pp. 111-118. Note that hydrogen acceptors other than the carbonate system exist in the lakes yielding an overestimate of DIC. We also computed average DIC values from the 05-06 and 07-08 seasons. DIC data changes relatively little over time; A paired t-test revealed that there was no significant difference between DIC for these 2 years (p>0.05). We report in the database DIC data computed from alkalinity titrations, and provide a link in the metadata to DIC data computed from averages of 05-06 and 07-08 DIC. The file containing DIC values computed from the average of previous and next season DIC values can be found in the following link: http://mcmlter.org/data/lakes/chemistry/core/LIMNO_DIC_0607.csv">http://mcmlter.org/data/lakes/chemistry /core/LIMNO_DIC_0607.csv Metadata Access Constraints: none Metadata Use Constraints: none annually McMurdo Dry Valleys LTER http://mcmlter.org/ pointOfContact