Acceptance and utilization of LTER data requires that:
FILE NAME: PRINCIPAL INVESTIGATOR: OTHERS: KEYWORDS: photosynthetic active radiation, light, extinction coefficient, lake, limnology, Antarctica
ABSTRACT: As part of the Long Term Ecological Research (LTER) project in the McMurdo Dry Valleys of
Antarctica, lakes were monitored for photosynthetic active radiation (PAR) levels. This data set exemplifies
the vertical profile of underwater PAR profiles in perennial ice covered lakes and ambient PAR measured at the
air-ice interface. Profile data can be used to calculate extinction coefficients for the water column and ice
layer.
VARIABLES: location name, location code, limno run, collection date, depth (m),
UwPAR (µmol photons m-2 s-1), ambient PAR (µmol photons m-2 s-1),
comments, file name
RESEARCH LOCATION: Samples were collected from the East Lake Bonney, West Lake Bonney, Lake Hoare, and Lake
Fryxell limnological sampling stations, located in the McMurdo Dry Valleys of Antarctica. Descriptions of these lakes
can be found in the McMurdo Dry Valley Lake
Descriptions file.
METHODS: A Licor LI-193SA spherical quantum sensor and a LI-190SA flat sensor
were attached to a Licor LI-1000 data logger to record instantaneous underwater PAR and ambient
PAR. Data were recorded in an outside incubation hole covered by a tarp, unless otherwise noted.
Once the sensor stabilized, the data were recorded.
TIMING: Samples were collected from the following sites and dates:
CITATIONS:
COMMENTS:
STATUS: Public Access (Type 1).
VARIABLE DESCRIPTION:
VARIABLE TYPE DESCRIPTION UNITS MISSING VALUE INDICATOR MINIMUM MAXIMUM PRECISION Location Name Text Name of lake where measurement was made none Required entry n/a n/a n/a Location Code Text Code for site where measurement was made none Required entry n/a n/a n/a Limno Run Text Code for lake's sampling location and date none Required entry n/a n/a n/a Collection Date Date Date on which sample was gathered mm/dd/yy Required entry 01/01/93 12/31/99 dd Depth (m) Number Distance below ice from which sample was drawn meters Required entry 1 60 1 uwPAR (µmol photons/m2/s) Number Underwater photosynthetically active radiation µmol photons/m2/second Null 0 100 0.01 Ambient PAR (µmol photons/m2/s) Number Ambient photosynthetically active radiation µmol photons/m2/second Null 0 2000 0.1 Comments Text Helpful hints about the sample Null n/a n/a n/a File Name Text Name of file in which data was submitted Null n/a n/a n/a LOG: 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 lktemps.metadata.txt and Metaparprofile9697.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.
NOTE: 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
(; (303)492-4639) so that the data can be
corrected or qualified. Thus, these data may be modified and future
data will be appended.
Season East Bonney West Bonney Hoare Fryxell
1993-1994 31-Oct-1993 28-Oct-1993 6-Nov-1993 17-Nov-1993
10-Nov-1993 13-Nov-1993 3-Dec-1993 7-Dec-1993
25-Nov-1993 27-Nov-1993 31-Dec-1993 9-Jan-1994
9-Dec-1993 9-Dec-1993
21-Dec-1993 25-Dec-1993
1994-1995 5-Nov-1994 6-Nov-1994 11-Nov-1994 15-Nov-1994
27-Nov-1994 27-Nov-1994 1-Dec-1994 5-Dec-1994
21-Dec-1994 21-Dec-1994 27-Dec-1994 31-Dec-1994
11-Jan-1995 13-Jan-1995 22-Jan-1995
1995-1996 30-Sep-1995 22-Sep-1995 8-Sep-1995 15-Sep-1995
7-Oct-1995 5-Oct-1995 9-Sep-1995 29-Sep-1995
18-Oct-1995 20-Oct-1995 10-Sep-1995 15-Oct-1995
9-Dec-1995 9-Dec-1995 26-Sep-1995 27-Nov-1995
2-Jan-1996 5-Jan-1996 10-Oct-1995 28-Dec-1995
23-Nov-1995
24-Dec-1995
1996-1997 5-Nov-1996 2-Nov-1996 10-Nov-1996 28-Oct-1996
23-Nov-1996 25-Nov-1996 4-Dec-1996 20-Nov-1996
19-Jan-1997 18-Jan-1997 13-Jan-1997 10-Jan-1997
1997-1998 10-Nov-1997 12-Nov-1997 16-Nov-1997 19-Nov-1997
21-Dec-1997 30-Dec-1997
1998-1999 10-Nov-1998 11-Nov-1998 3-Nov-1998 29-Oct-1998
7-Dec-1998 9-Dec-1998 1-Dec-1998 24-Nov-1998
31-Dec-1998 1-Jan-1999 26-Dec-1998 21-Dec-1998
1999-2000 6-Nov-1999 11-Nov-1999 17-Nov-1999 31-Oct-1999
4-Dec-1999 5-Dec-1999 12-Dec-1999 28-Nov-1999
29-Dec-1999 30-Dec-1999 4-Jan-2000 22-Dec-1999
none
none