EXPLORERS COVE METEOROLOGICAL STATION


Photo taken by Thomas Nylen - 1999-2000 Season
All Rights Reserved. Reproduced with permission.
For a panoramic view of the valley near the station, click here


Acceptance and utilization of LTER data requires that:
CONTACTS:

MCM LTER Data Manager: Chi Yang
Address:Institute of Arctic and Alpine Research, Campus Box 450, University of Colorado Boulder, Colorado 80309-0450
Phone:(303) 492-4639
E-Mail: Chi.Yang@colorado.edu

PRINCIPAL INVESTIGATOR: Andrew G. Fountain
Address: Department of Geology, Portland State University, Portland OR, 97207-0751
Phone:(503)725-3022
E-Mail:fountaina@pdx.edu

OTHERS:Thomas Nylen
Address:Department of Geology, Portland State University, Portland OR, 97207-0751
Phone:(503)725-3355
E-Mail:nylent@pdx.edu


METEOROLOGICAL STATION MEASUREMENTS
KEYWORDS: meteorology, temperature, air temperature, soil temperature, precipitation, wind, relative humidity, radiation

ABSTRACT: As part of the Long Term Ecological Research in the McMurdo Dry Valleys of Antarctica, meteorological data was collected from various locations throughout Taylor, Wright and Victoria Valleys. These files contain data for Explorers Cove meteorology station.

VARIABLES: Samples are represented using the following variable names:

Variable Name Description
Dataset Code Code for given set of information from Explorers Cove Met Station
MetLocID Location code for Explorers Cove meteorology station
Date Date/time of sample (McMurdo time)
AirT3m Average air temperature at 3 m above ground
AirTdel3m1 Air temperature at 3 m above ground minus air temperature at 1 m above ground
AirT Comments Comments about air temperature
Ppt (mm) Unevaporated precipitation
Ppt Comments Comments about precipitation
RH Relative humidity
RH Comments Comments about relative humidity
SoilT0cm Soil temperature at 0 cm depth
SoilT5cm Soil temperature at 5 cm depth
SoilT10cm Soil temperature at 10 cm depth
SoilT Comments Comments about soil temperature
PAR Photosynthetically active radiation
SwRadIn Incoming shortwave radiation
SwRadOut Outgoing shortwave radiation
Radiation Comments Comments about radiation measurements (PAR, shortwave)
WDir Average wind direction
WDirStD Standard deviation of wind direction
WSpd Wind speed
WSpdMax Maximum wind speed
WSpdMin Minimum wind speed
Wind Comments Comments about wind speed

RESEARCH LOCATION: The Explorers Cove meteorology station is located at a latitude of 77 3.08314 S, a longitude of 163 25.0514 E, and an elevation of 25.7466 meters above sea level. Descriptions of this and other McMurdo Dry Valley meteorology stations can be found at http://huey.colorado.edu/LTER/datasets/meteorology/metlocs.html.

METHODS: At the start of the first McMurdo LTER field season (1993-1994), Explorers Cove station was one of only two meteorological stations operating on the floor of the McMurdo Dry Valleys. The U.S. Geological Survey continued to manage the station. From November 24, 1995 to February 26, 1996, precipitation levels were sampled every hour for the long-term ecological research program. On February 26, 1996, the signal from the precipitation gage went dead and remained so until new equipment was installed in November, 1997. As a result there is a gap in the data collected at Explorers Cove meteorological station.

In November, 1997, a new station with all new sensors mounted on Clow's old tripod was set up. At that time, the station was set up to sample sensors every 30 seconds and send summary statistics (for example, averages and maximums) to solid-state storage modules every 15 minutes. This has resulted in approximately 20 values being recorded for final storage in the more recent output intervals. Primary measurements now made on Explorers Cove meteorology station, instrumentation used, and time of initiation are shown in the following table:


Measurement

Starting Season

Ending Season

Instrument Used
Air temperature @ 3 m
1997/1998

1999/2000

1999/2000

---

Campbell Scientific 207 temp/rh probe

Campbell Scientific 107 temp probe

Relative humidity @ 3 m
1997/1998

1999/2000

1999/2000

---

Campbell Scientific 207 temp/rh probe

Vaisala HMP45C RH probe

Air temperature difference between 1 m & 3 m heights
1997/1998
2002/2003
Chromel-constantan thermocouple wire
Soil temperature @ 0 cm
1997/1998
---
Campbell Scientific 107B temperature probe
Soil temperature @ 5 cm
2002/2003
---
Campbell Scientific 107 temperature probe
Soil temperature @ 10 cm
2002/2003
---
Campbell Scientific 107 temperature probe
Wind speed
1997/1998
---
R.M. Young model 05103 wind monitor
Wind direction
1997/1998
---
R.M. Young model 05103 wind monitor
Solar Flux (incoming)
1997/1998
---
LI-COR model L1200S silicon pyranometer
Solar Flux (outgoing)
1997/1998
---
LI-COR model L1200S silicon pyranometer
PAR
1997/1998
---
LI-COR model 190SB quantum sensor
Precipitation
1995/1996
---
Belfort precipitation gage with BEl natural binary shaft encoder. Custom-made nipher shields provided by Canada's Atmospheric Environment Service.

TIMING: Data was gathered from the Explorers Cove meteorology station on the dates and frequencies listed in the link below. Due to regular station maintenance, occasional short gaps (hours) with missing data occurs. Longer intervals (several months) with missing data have occasionally occurred due to storage module problems, but this is minimized through the regular station upkeep every austral summer. Click here to see the dates and frequencies.

CITATIONS: Doran, Peter T., Gayle L. Dana, Jordan T. Hastings and Robert A. Wharton, Jr. 1995. McMurdo Dry Valleys Long-Term Ecological Research (LTER): LTER automatic weather network (LAWN). Antarctic Journal of the U.S. 30(5): 276-280.

COMMENTS: Meteorological data is collected year-round at each of the stations in the McMurdo Dry Valleys of Antarctica. After retrieving this data (usually every January), the parameters that are recorded are processed from level 0 (raw) to level 1 (processed, provided on the web). The raw data file descriptions and task lists summarize what was done to get from level 0 to level 1.

STATUS: Public Access (Type 1).

VARIABLE DESCRIPTION:

variable

type

description

units

missing value indicator

minimum

maximum

precision

Dataset code

Text

Code for given set of information for Explorers Cove meteorology station

None

Required entry

n/a

n/a

n/a

MetLocID

Text

Location code for Explorers Cove meteorology station

None

Required entry

n/a

n/a

n/a

Date

Date

Date/time of sample (McMurdo time)

MM/DD/YY HH24:MM

Required entry

12/01/94 00:00

12/31/04 23:59

MM (minutes)

AirT3m

Number

Average air temperature at 3 m above ground

degrees celcius

Null

-70

15

0.01

AirTdel3m1

Number

Air temperature at 3 m minus air temperature at 1 m

degrees celcius

Null

n/a

n/a

0.01

AirT Comments

Text

Helpful hints on air temperatures

None

Null

n/a

n/a

n/a

Ppt (mm)

Number

Unevaporated precipitation

millimeters

Null

n/a

n/a

0.1

Ppt Comments

Text

Helpful hints on precipitation measurements

None

Null

n/a

n/a

n/a

RH

Number

Relative humidity

percent

Null

0

100

0.1

RH Comments

Text

Helpful hints on relative humidity

None

Null

n/a

n/a

n/a

SoilT0cm

Number

Soil temperature at 0 cm depth

degrees celcius

Null

-70

25

0.01

SoilT5cm

Number

Soil temperature at 5 cm depth

degrees celcius

Null

-70

25

0.01

SoilT10cm

Number

Soil temperature at 10 cm depth

degrees celcius

Null

-70

25

0.01

SoilT Comments

Text

Helpful hints on soil temperatures

None

Null

n/a

n/a

n/a

PAR

Number

Photosynthetically active radiation

µmols/second/meter2

Null

0

2000

0.1

SwRadIn

Number

Incoming shortwave radiation/solar flux

W/m2

Null

0

900

0.1

SwRadOut

Number

Outgoing shortwave radiation/solar flux

W/m2

Null

0

900

0.1

Radiation Comments

Text

Helpful hints on shortwave radiation/solar flux measurements

None

Null

n/a

n/a

n/a

WDir

Number

Average wind direction

degrees from north

Null

0

360

0.1

WDirStD

Number

Standard deviation of wind direction

degrees from north

Null

0

n/a

0.1

WSpd

Number

Wind speed

meters per second

Null

0

n/a

0.1

WSpdMax

Number

Maximum wind speed

meters per second

Null

0

n/a

0.1

WSpdMin

Number

Minimum wind speed

meters per second

Null

0

n/a

0.1

Wind Comments

Text

Helpful hints on wind measurements

None

Null

n/a

n/a

n/a

FLAGS: Flags used during data processing:

"#": Bogus value, initialized but never calculated
"B": Recorded by instrument,but known to be "bad data"
"F": Recorded by instrument, but apparently flawed
"M": Supposedly recorded by instrument, but missing
"N": Not available/applicable (e.g. WDir when WSpd=0)
"R": Out of Range (user-adjustable limits)
"*": Subjectively voided

In addition, flags were found that were not included in the list above. Peter Doran was therefore contacted to find out how to translate the flags for "S", "U" and "V". He advised to use the following:

"S": Negative value generated by noise in the system zeroed out (eg. incoming shortwave radiation level should not be negative, so convert negative value to zero)
"U": Constant ice surface ablation on the glaciers causes the 20-centimeter ice temperature probe to continually become shallower. The probe depth is therefore not well known.
"V": Constant ice surfaceablation on the glaciers causes the 1-meter ice temperature probe to continually become shallower. The probe depth is therefore not wellknown.

Since the flags in the data files were added to values that were recorded, rather than appearing as a separate variable (eg. 0.0N, as opposed to 0.0, N), it was necessary for the data manager to revise these files so that the measurements were represented in numeric format; the flags would be in text format. Denise Steigerwald therefore imported the data into Microsoft Access, created comment fields for categories such as air temperature, humidity, wind, radiation, and soil temperature, and moved the suffixes described above to these comments fields. The comments were then expanded from the single letter codes to short descriptions of what was occurring.


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 (telephone: 303-492-4639) so that the data can be corrected or qualified. Thus, these data may be modified and future data will be appended.