Note: This data set was first published on the 1998 CAPS CD.
The text for this document was taken unchanged from that CD.

See also Description of Data Files.

Ground temperatures in ice-cemented ground at Linnaeus Terrace, Dry Valleys, Antarctica

File description:

Soil temperatures were measured with Campbell 107 soil thermistors. Thermistors were placed at 0, 17, 23 (just above the ice-cemented permafrost) and 40 cm depth. To emplace the sensors, first a soil pit was dug to the level of ice-cemented permafrost. Then a hammer drill was used to make a narrow, 15 cm deep, hole into the ice-cemented ground. The thermistor was placed into the drill hole. This procedure caused minimal disturbance to the ice-cemented ground. Air temperature and humidity were measured with a Campbell 207 air probe. The temperature on the surface of an outcrop of Beacon sandstone was measured with a T-type thermocouple. Sunlight was measured with a LiCor 200 pyranometer. The sensors were deployed during Jan 1993 but (due to equipment failure) data storage only began 6 Jan 1994 and was continued until 16 Jan 1995.

All temperature sensors were removed after the data collection interval and calibrated in the laboratory. Calibrations were applied using the Steinhart and Hart (1968) representations for the temperature dependence of the thermistor resistance. This was necessary since the instrumental calibration for the 107 thermistor provided by Campbell did not extend below -40C. After correction, the error in the temperature measurement is estimated to be less than 0.2 C and error in the humidity measurement was <10%. However, an important caveat is that the Campbell 207 RH sensor has high errors for relative humidity values below 15% --- tending to systematically overestimate values by more than 10% humidity. The error in the averaged light measurement is less than 10 W/m2 All sensors were sampled once every 10 minutes and averages of three measurements were written to final memory every 30 minutes corresponding to 48 recordings each day.

Bibliography:

McKay, C.P., M.T. Mellon, E.I. Friedmann, Soil temperatures and stability of ice-cemented ground in the McMurdo Dry Valleys, Antarctica, Antarctic Science, 10, 31-38, 1998.

Please cite these data as follows:

McKay, C.P. 1998. Ground temperatures in ice-cemented ground at Linnaeus Terrace, Dry Valleys, Antarctica. In: International Permafrost Association, Data and Information Working Group, comp. Circumpolar Active-Layer Permafrost System (CAPS), version 1.0. CD-ROM available from National Snow and Ice Data Center, nsidc@kryos.colorado.edu. Boulder, Colorado: NSIDC, University of Colorado at Boulder.

Data format:

Data are stored in columns of ASCII data:
entries are:

1. Digital day of year in 1994
2. Air temperature
3. Air relative humidity
4. Sunlight, W/m2
5. Soil surface temperature
6. Temperature at 17 cm depth
7. Temperature at 23 cm depth
8. Temperature at 40 cm depth
9. Temperature on surface of rock

First record

   6.469  -5.29 24.99  757.03  11.37  -5.93  -9.10 -11.34   0.30

SITE DATA FILE:

 *Site no.: LT

 *Source of data: (enter names)
         Name of investigator: Christopher P. McKay
         Name of institute:NASA Ames Research Center

 *Data type: (check or specify)
         Temperature log  XXXXX
 
 *Location: (enter Long. Lat. or UTM )
 Linnaeus Terrace 77 36'S, 161 05'E, 1600 m elevation.

 *Geodetic datum: none
 
 *Elevation a.s.l.: (enter elevation in meters or feet)
         (m): 1600 m
         (feet):
 
 *Aspect (slope orientation): (check one)
         North
         Northeast
         East
         Southeast
         South
         Southwest
         West
         Northwest
         Complex (undulating)
      x  Level 
 
 *Slope angle (degree): (enter the numerical value)
flat 

 *Landform: (check one)
         Blanket
         Fan
         Hummock
         Inclined
         Level
         Rolling
    x    Ridged
         Steep
         Terraced
         Undulating
         Veneer
         Other (specify)
 
 *Material: (check one)
         Anthropogenic
         Colluvial
         Eolian
         Fluvial
         Lacustrine
         Alluvial
         Residual
         Morainal (till)
         Volcanic
         Marine
         Organic
   x     Bedrock
         Ice
         Other (specify)
 
 *Texture of material: (check one)
         Clay
         Silt
         Loam
         Coarse, gravelly
         Diamicton
    x    sandy soil
 
 *Drainage: (check one)
         Very rapidly drained
         Rapidly drained
         Well drained
   x     Moderately well drained
         Imperfectly drained
         Poorly drained
         Very poorly drained
 
 *Vegetation type: (check one)
         Closed coniferous forest
         Open coniferous forest
         Deciduous forest
         Mixed deciduous and coniferous forest
         Grassland
         Wetland (including peatland)
         Tundra, alpine
         Tundra, high shrub
         Tundra, medium shrub
         Tundra, low shrub
         Tundra, broken herb
    x    Unvegetated surface
 
 Vegetation cover (%): (enter % cover)
     0 

 Anthropogenically disturbed site: (check one)
         Yes
   x     No
 
 Fire history: (enter number of years since fire)
   none
 
 Remarks: (free format text - any additional information about the
 site that may be important to users of the data) none

INTERNATIONAL PERMAFROST ASSOCIATION GLOBAL GEOCRYOLOGICAL DATABASE

Metadata to accompany shallow ground temperature measurements

The following standard was discussed in a small working group at the IPA/WDC-A meeting in Boulder, December 1996. The standard concerns the minimum metadata to accompany measurements of permafrost temperatures, particularly non-borehole data. Standards and formats for borehole data is proposed in a separate standard.

     /////////////////////////////////////////////////

Shallow ground temperature measurements are:

Manual...      XXX       Automatic (logger)...

Temperature sensor is:

  XX thermistor...
     thermocouple...
     mercury thermometer...
     other...

Sampling rate (period of measurement) 10 min

     and averaging period of individual measurements 30 min

Time standard used is local time zone XXXX

Accuracy is:

     plus/minus 0.2 degrees Celsius in temperature

      plus/minus 0.03 meters in depth

     
Comments: none