uid=MCM,o=EDI,dc=edirepository,dc=org all public read PAR_INSTANT Cristina Takacs-Vesbach cvesbach@unm.edu http://www.wildmicrobiome.org https://orcid.org/0000-0002-5535-2201 John Priscu jpriscu@montana.edu https://orcid.org/0000-0001-5807-6364 McMurdo Dry Valleys LTER http://mcmlter.org/ Jade Lawrence jlawrence1@unm.edu https://orcid.org/0009-0005-2603-342X field technician Renée Brown rfbrown@unm.edu https://orcid.org/0000-0002-4986-7663 data manager Amy Chiuchiolo

LRES, 334 Leon Johnson Hall Bozeman MT 59717 US

(406) 994-2360 (406) 994-5863 achiuchiolo@montana.edu former field crew Inigo San Gil

Department of Biology, MSC03 2020 University of New Mexico Albuquerque NM 87131 US

(505) 277-2625 (505) 277-2541 isangil@lternet.edu former data manager 2025-10-13 English

As part of the Long Term Ecological Research (LTER) project in the McMurdo Dry Valleys of Antarctica, PAR is measured at one depth during primary production experiments in Dry Valley Lakes. This data set quantifies instantaneous underwater PAR at 10-meter depths in Lakes Bonney and Hoare, and at 7-meter depth in Lake Fryxell (depths vary after 2008, check data file for actual depth). Ambient PAR was also measured at the air-ice interface from each of these lakes.

Antarctica lake light limnology PAR photosynthetic active radiation photosynthetically active radiation radiation Station Keywords lakes light photosynthetically active radiation LTER Controlled Vocabulary

This data package is released under the Creative Commons Attribution 4.0 International License (CC BY 4.0; http://creativecommons.org/licenses/by/4.0/), which allows consumers (hereinafter referred to as “Data Users”) to freely reuse, redistribute, transform, or build on this work (even commercially) so long as appropriate credit is provided. Accordingly, Data Users are required to properly cite this data package in any publications or in the metadata of any derived products that result from its use (in whole or in part). A recommended citation is provided on the summary metadata page associated with this data package in the McMurdo Dry Valleys LTER Data Catalog (https://mcmlter.org/data), and a generic citation may be found on the summary metadata page in the repository where this data package was obtained. When these data contribute significantly to the contents of a publication, Data Users must also acknowledge that data were provided by the NSF-supported McMurdo Dry Valleys Long Term Ecological Research program (OPP-2224760). This data package has been released in the spirit of open scientific collaboration. Hence, Data Users are strongly encouraged to consider consultation, collaboration, and/or co-authorship (as appropriate) with the data package creator(s). Data Users should be aware these data may be actively used by others for ongoing research; thus, coordination may be necessary to prevent duplicate publication. Data Users should also recognize that misinterpretation of data may occur if they are used outside the context of the original study. Hence, Data Users are urged to contact the data package creator(s) if they have any questions regarding methodology or results. While substantial efforts are made to ensure the accuracy of this data package (with all its components), complete accuracy cannot be guaranteed. Periodic updates to this data package may occur, and it is the responsibility of Data Users to check for new versions. This data package is made available “as is” and comes with no warranty of accuracy or fitness for use. The creator(s) of this data package and the repository where these data were obtained shall not be liable for any damages resulting from misinterpretation, use, or misuse of these data. Finally, as a professional courtesy, we kindly request Data Users notify the primary contact referenced in the metadata when these data are used in the production of any derivative work or publication. Notification should include an explanation of how the data were used, along with a digital copy of the derived product(s). Thank you.

https://mcm.lternet.edu/content/underwater-photosynthetically-active-radiation-par-situ-lake-primary-production-experiments 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): 54.7 162.353210449219 162.536209106445 -77.697700500488 -77.724441528320 57 57 meter 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): 25.2 163.048782348633 163.259582519531 -77.597076416016 -77.622711181641 18 18 meter 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): 17.5 162.784423828125 162.935836791992 -77.623085021973 -77.639259338379 73 73 meter 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): 2.9 163.812332153320 163.886840820313 -78.094047546387 -78.101478576660 240 240 meter 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): 10.1 162.269104003906 162.354934692383 -77.714805603027 -77.727287292480 57 57 meter 1995-09-14 2024-12-24 Data from these tables 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 ascii text files submitted. 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. Because two different approaches were taken in collecting this data (instantaneous PAR and integrated PAR), resulting in measurements that differed in scale (micromol photons/m2/second vs. mol photons m-2 hr-1) and dates (limno run 2 vs limno run 1 of season), the data was separated into two files: instantaneous measurements and integrated measurements. These files were imported into Microsoft Access on INSTAAR's Unix system, and can currently be found there. The files were then exported in ascii, comma delimited text and MS-DOS text (table layout) on the MCM LTER web site. Information for the metadata was obtained from the Metaparlogged9697.rtf and Metaparlogged9798.rtf files. The files were called up using Microsoft Word version 6.0. Text from these files was used to create this page in html format. While processing the 1997-98 data, the data manager noticed that the integrated PAR data contained a jump in the dates provided for the Lake Hoare records. Data collected in limno run HOA9798L1 contained 11/15/1997 and 12/16/1997 dates. Since there is not usually a gap like this for a given limnology run, a correction was necessary. John Priscu and Craig Wolf were contacted in November 1999 to look into this, but since it was the middle of the field season, it took some time to resolve it. On 28-Feb-2000, the HOA9798L1 records showing dates of 12/16/1997 were corrected to 11/16/1997. In 2006, Chris Gardner and Inigo San Gil converted all metadata to EML to comply with interoperability mandates at LTER. In 2014, Inigo San Gil introduced metadata enhancements (publication Date, methods, markup, language, entity level, etc) and placed the metadata into the Drupal Ecological Information Management System. McMurdo Dry Valleys LTER http://mcmlter.org/ McMurdo Dry Valleys LTER http://mcmlter.org/ McMurdo Dry Valleys LTER

A Licor LI-193SA spherical quantum sensor and a LI-190SA flat sensor are attached to a Licor LI-1000 data logger to record underwater PAR and ambient PAR. Underwater PAR data are recorded in the sampling hole covered by the Weatherport, whereas ambient PAR is measured approximately 10 m away from the Weatherport. The Licor LI-1000 queries ambient and underwater PAR at 5 second intervals an records mean PAR data (micromol photons m-2 s-1) every 10 minutes. We began using a LI-1400 at the start of the 1213 season. The Licor LI-1400 queries ambient and underwater PAR at 5 second intervals and records mean PAR data (micromol photons m-2 s-1) every 5 minutes. Starting in the 23/24 season, the LI-1400 datalogger was replaced with a LI-1500 datalogger. Due to increased memory in the new datalogger, we now average both parameters every 60 seconds and log every 60 seconds. Previously, the LI-1400 used a sampling period of 5 seconds and a logging period of 5 minutes. Additional notes: EB0304L1: McKenna: no data available. LICOR was turned off by accident FRX0405L2: No logged PAR data for FRX L2. FRX L2: 1 Dec 04 (0744): PPR incubation put in water; 2 Dec 04 (0815): PPR incubation taken out of water. HOR2223L2: no HOR L2 measurements (no PPR incubation)

PAR_INSTANT Photosynthetically active radiation during in-situ experiments mcmlter-lake-par_instant-20251013.csv 8327642 1 1 \n column , " https://mcm.lternet.edu/sites/default/files/data/mcmlter-lake-par_instant-20251013.csv DATASET_CODE DATASET_CODE Code to ID the data table string Code to ID the data table LIMNO_RUN Limno Run Code for lake's sampling location and date string Code for lake's sampling location and date LOCATION NAME LOCATION NAME Name of lake where measurement was made string Name of lake where measurement was made LOCATION CODE LOCATION CODE Code for site where measurement was made string Code for site where measurement was made DATE_TIME Collection Date Date on which sample was gathered date mm/dd/yyyy HH:MM DEPTH (m) DEPTH (m) Distance below the piezometric water level at which measurement was taken. meter 1 real 1 60 Required entry None given UwPAR (umol photons/m2/s) UwPAR (umol photons/m2/s) Underwater photosynthetically active radiation umolphotons/m2/second 0.01 real 0 100 Null None given Ambient PAR umol photons/m2/s Ambient PAR umol photons/m2/s Ambient photosynthetically active radiation umolphotons/m2/second 0.1 real 0 2000 Null None given COMMENTS COMMENTS Helpful hints about the sample string Helpful hints about the sample FILE NAME FILE NAME Name of file in which data was submitted string Name of file in which data was submitted DEPTH MASL DEPTH MASL Depth referred to the Sea level. Distance below Mean Average Sea Level meter 1 real