Antarctica - Wilkes Land snow / firn temperatures

Measurements of temperature within the snow / firn cover in Wilkes Land East Antarctica were made along the routes of oversnow traverses operating out of Casey (66.6 S 110 E). In general, measurements were made at a nominal depth of ten metres as a first estimate of mean annual surface temperature of the ice sheet, and for many sites, at some additional depths, typically around twenty metres. Actual depths of measurements are included with the temperature data as well as date of observation. No attempt has been made to apply any correction for seasonal or interannual variation.

Two different methods were used to drill the access holes: an ice coring auger (usually PICO drill, originally SIPRE drill); a steam drill. In some areas depth of drilling was limited by problems associated with the texture of the firn and difficulties in recovery of material from the hole.

Where relevant, date of drilling is included with the data, or time elapsed between drilling and temperature measurement. Temperature measurements were made using 100 ohm platinum resistance elements with resistance measured using a 'Leeds and Northrup' resistance bridge. The bridge uses a zero/nul measurement technique, thus avoiding heating effects in the sensor Refer quality entry for further details).

These data form part of the data collected for ASAC projects 456 (Properties and Structure of Antarctic Snow and Ice ), 458 (Characteristics, Dynamics and Mass Budget of the Ice Sheet in Wilkes Land ) and 2224 (Glacier dynamics and mass discharge from the Antarctic ice sheet, 45 degrees -160 degrees E) - ASAC_456, ASAC_458, ASAC_2224).

The fields in this dataset are:

site_id (the marker code of the measurement site)

observation_date (date on which measurement was made, in ISO8601 format yyyy-mm-dd)

observation_date_year (year of measurement date)

observation_date_month (month of measurement date)

observation_date_day (day of measurement date)

temperature (degrees C)

depth_of_observation (m)

latitude

longitude

drill_type

date_drilled

comment

days_between_drilling_and_measurement