关键词: 积累率;自动气象站(AWS);南极冰盖;气温修正

Abstract:

The heights of the Automatic Weather Station(AWS)sensors are nominal,which change with the snow accumulation or ablation,over the Antarctic ice sheet.Therefore,the measured data can not be used directly.In this study,air temperatures from three AWSs,deployed on the traverse route from Zhongshan station to Dome A on East Antarctica ice sheet,are corrected to a certain real height relative to the snow surface with the impacts of snow accumulation,to improve the authenticity and representativeness of the observation data from AWS.The results showed that(1)the average accumulation at Dome A,Eagle and LGB69 is approximately 0.11 m,0.30 m and 0.49 m snow per year,and the corresponding annual mean air temperature difference at 1m height between corrected and measured is 0.34 ℃,0.29 ℃ and 0.35 ℃,respectively.The values are less than 0.1 ℃ at 2 m and 4 m heights.(2)The impact on air temperature from accumulation is decreasing with the height from the surface.(3)The relationship between air temperature correction and accumulation is not a simple direct proportion.It also relates to the characteristics of air temperature seasonal variation and the intensity of the local surface inversion.(4)The average air temperature correction is almost positive except in summer without inversion at times.The magnitude of it is mainly determined by accumulation and the intensity of surface inversion.