Estimation of ICESat intercampaign elevation biases from comparison of lidar data in East Antarctica

摘要

[1] The Ice, Cloud, and land Elevation Satellite (ICESat) laser campaign elevation biases are estimated from an analysis of ICESat and airborne Land, Vegetation, and Ice Sensor lidar intrasensor and intersensor elevation differences from two regions of the Antarctic ice sheet that experienced minimal surface elevation change. Elevation observations are corrected for a combination of accumulation, melting, and firn densification processes and glacial isostatic adjustment. ICESat elevations are adjusted for the saturation and Gaussian-Centroid corrections. Relative to laser campaign L3I, biases are found to be less than ~8 cm, except for campaign L2E at 14.72 cm corresponding to the time of a significant accumulation anomaly in East Antarctica. The intercampaign bias trend estimated from intersensor elevation differences computed over campaigns L2A to L2F (September 2003 to October 2009) excluding L2E is 1.04 ± 0.48 cm/yr. The intercampaign bias trend represents a correction to ICESat derived Antarctica mass balance of 117 ± 53 Gt/yr.