LAKE HOARE METEOROLOGICAL STATION


Photo taken by Thomas Nylen - 2002 - 2003 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 the Lake Hoare meteorology station (in Taylor Valley).

VARIABLES: Samples are represented using the following variable names:

Variable Name Description
Dataset Code Code for given set of information from Lake Hoare meteorology station
MetLocID Location code for Lake Hoare 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
AirTMax Maximum air temperature at 2.5 - 3 m above ground
AirTMin Minimum air temperature at 2.5 - 3 m above ground
AirT Comments Comments about air temperature
PresSta Atmospheric Pressure
PresSta Comments Comments about atmospheric pressure
Ppt Unevaporated precipitation
Ppt Comments Comments about unevaporated 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 (photosynthetically active & incoming/outgoing shortwave radiation)
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 Hoare meteorology station is located at a latitude of 77 1.45324 S, a longitude of 162 54.02422067 E, and an elevation of 77.1 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: The Lake Hoare meteorology station was one of two meteorological stations operating on the floor of Taylor Valley at the start of the first McMurdo LTER field season (1993-1994). The McMurdo LTER team took control of this station during this season, and replaced it with a new station, located a few meters above the old site to avoid rising lake levels.

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 10 minutes between December 18, 1993 and January 16, 1994, every three hours between January 16, 1994 and November 18, 1994, every 20 minutes between November 18, 1994 and November 28, 1995, and every 15 minutes thereafter. This has resulted in approximately 20 values being recorded for final storage in every output interval. Primary measurements made on Lake Hoare meteorology station, instrumentation used, and time of initiation are shown in the following table.

On Jan 26, 2002 a second datalogger and the TE525MM Tipping bucket rain gage was installed. The tipping bucket records the number of tips every 15 minutes. Three soil probes, 0, 5 and 10 cm below the surface were added to the datalogger on Dec 29, 2002.


Measurement
Starting Season
Ending Season

Instrument Used

Air temperature @ 3 m

1993/1994

1999/2000

1999/2000

---

Campbell Scientific 207 temp/rh probe

Campbell Scientific 107 temp probe

Air temperature difference between 1 m & 3 m heights

1993/1994

---

Chromel-constantan thermocouple wire

Relative humidity @ 3 m

1993/1994

1999/2000

1999/2000

---

Campbell Scientific 207 temp/rh probe

Vaisala HMP45C RH probe

Soil temperature @ 0 cm

1993/1994

2002/2003

1995/1996

---

Campbell Scientific 107B temperature probe

Campbell Scientific 107 temperature probe

Soil temperature @ 5 cm
1993/1994

2002/2003

1995/1996

---

Campbell Scientific 107B temperature probe

Campbell Scientific 107 temperature probe

Soil temperature @ 10 cm

1993/1994

2002/2003
1995/1996

---

Campbell Scientific 107B temperature probe

Campbell Scientific 107 temperature probe

Wind speed

1993/1994

---

R.M. Young model 05103 wind monitor

Wind direction

1993/1994

---

R.M. Young model 05103 wind monitor

Solar Flux (incoming)

1993/1994

---

LI-COR model L1200S silicon pyranometer

Solar Flux (outgoing)

1993/1994

---

LI-COR model L1200S silicon pyranometer

PAR

1993/1994

---

LI-COR model 190SB quantum sensor

Precipitation

1994/1995

2001/2002

2000/2001

---

Belfort precipitation gage with BEl natural binary shaft encoder. Custom-made nipher shields (Canada's Atmospheric Environment Service)
TE525MM Tipping bucket rain gage

Barometric Pressure

1994/1995

---

Vaisala model PTA427 barometric pressure sensor

TIMING: Data was gathered from the Lake Hoare 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 for the main station and the second station which measures precipitation and soil temperatures.

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 Lake Hoare meteorology station

None

Required entry

n/a

n/a

n/a

MetLocID

Text

Code representing Lake Hoare 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

AirTMax

Number

Maximum air temperature at 2.5 - 3 m above ground

degrees celcius

Null

-70

15

0.01

AirTMin

Number

Minimum air temperature at 2.5 - 3 m above ground

degrees celcius

Null

-70

15

0.01

AirT Comments

Text

Helpful hints on air temperatures

None

Null

n/a

n/a

n/a

PresSta

Number

Atmospheric Pressure

mbar

Null

n/a

n/a

0.1

PresSta Comments

Text

Helpful hints on atmospheric pressure measurements

None

Null

n/a

n/a

n/a

Ppt

Number

Unevaporated precipitation

millimeters

Null

n/a

n/a

0.1

Ppt Comments

Text

Helpful hints on unevaporated precipitation measurements

None

Null

n/a

n/a

n/a

RH

Number

Relative humidity

percent

Null

n/a

n/a

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

n/a

n/a

0.01

SoilT5cm

Number

Soil temperature at 5 cm depth

degrees celcius

Null

n/a

n/a

0.01

SoilT10cm

Number

Soil temperature at 10 cm depth

degrees celcius

Null

n/a

n/a

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

n/a

n/a

0.1

SwRadIn

Number

Incoming shortwave radiation/solar flux

W/m2

Null

n/a

n/a

0.1

SwRadOut

Number

Outgoing shortwave radiation/solar flux

W/m2

Null

n/a

n/a

0.1

Radiation Comments

Text

Helpful hints on photosynthetically active, shortwave radiation/solar flux measurements

None

Null

n/a

n/a

n/a

WDir

Number

Average wind direction

degrees from north

Null

n/a

n/a

0.1

WDirStD

Number

Standard deviation of wind direction

degrees from north

Null

n/a

n/a

0.1

WSpd

Number

Wind speed

meters per second

Null

n/a

n/a

0.1

WSpdMax

Number

Maximum wind speed

meters per second

Null

n/a

n/a

0.1

WSpdMin

Number

Minimum wind speed

meters per second

Null

n/a

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.