PAR_INSTANT English utf8 dataset McMurdo Dry Valleys LTER http://mcmlter.org/ 2019-06-20 ISO 19115-2 Geographic Information - North American Profile Metadata - Data with Biological Extensions ISO 19115-2:2009(E) Underwater Photosynthetically Active Radiation (PAR) from in-situ Lake Primary Production Experiments in the McMurdo Dry Valleys of Antarctica (1995-2024, ongoing) 2019-06-20 publication Cristina Takacs-Vesbach University of New Mexico https://www.unm.edu/ cvesbach@unm.edu http://www.vesbachlab.org pointOfContact John Priscu Montana State University http://www.montana.edu/ jpriscu@montana.edu pointOfContact documentDigital 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. Name: Jade Lawrence Role: field 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 http://mcmlter.org/ unknown 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. 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 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 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 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 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 1995-09-14 2024-12-24 https://mcm.lternet.edu/sites/default/files/data/mcmlter-lake-par_instant-20251013.csv PAR_INSTANT eng; US McMurdo Dry Valleys LTER PAR_INSTANT Data Source Definition : Photosynthetically active radiation during in-situ experiments Record Delimiter : \n Number of Header Lines : 1 Number of Footer Lines : 1 Orientation : Column Quote Character : "Field Delimiter : , false DATASET_CODE Code to ID the data table 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 HH:MM DEPTH (m) Distance below the piezometric water level at which measurement was taken. UwPAR (umol photons/m2/s) Underwater photosynthetically active radiation Ambient PAR umol photons/m2/s Ambient photosynthetically active radiation COMMENTS Helpful hints about the sample FILE NAME Name of file in which data was submitted DEPTH MASL Depth referred to the Sea level. Distance below Mean Average Sea Level DBF https://mcm.lternet.edu/sites/default/files/data/mcmlter-lake-par_instant-20251013.csv dataset 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) Metadata Access Constraints: none Metadata Use Constraints: none annually McMurdo Dry Valleys LTER http://mcmlter.org/ pointOfContact