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:MarkerDateTemperature (degrees C)Depth of Observation (m)LatitudeLongitudeDrillTime since drillingComments

南极洲威尔克斯地东部雪/粒雪（firn）覆盖层内的温度测量，是沿着从Casey站（南纬66.6度，东经110度）出发的雪地横穿路线开展的。通常，测量在标称深度10米处进行，作为冰盖年平均表面温度的初步估计；此外，许多站点还在其他深度（典型值约20米）进行了补充测量。温度数据中包含实际测量深度及观测日期，未对季节或年际变化进行任何校正。

钻孔采用两种方法：冰芯螺旋钻（通常为PICO钻，最初为SIPRE钻）和蒸汽钻。部分地区的钻孔深度受限于粒雪质地问题及孔内材料回收困难。

相关数据中包含钻孔日期，或钻孔与温度测量之间的时间间隔。温度测量使用100欧姆铂电阻元件，其电阻值通过“Leeds and Northrup”电阻桥测定。该电阻桥采用零位测量技术，可避免传感器发热效应（详见质量条目）。

这些数据是ASAC项目456（南极雪与冰的性质及结构）、458（威尔克斯地冰盖的特征、动力学与物质平衡）及2224（南极冰盖冰川动力学与物质排放，东经45度-160度）所收集数据的一部分——ASAC_456、ASAC_458、ASAC_2224。

本数据集包含以下字段：标记点（Marker）、日期（Date）、温度（摄氏度，degrees C）、观测深度（米，m）、纬度（Latitude）、经度（Longitude）、钻孔方式（Drill）、钻孔后时间间隔（Time since drilling）、备注（Comments）