Height variation detection in polar regions from ICESat satellite altimetry

Laser altimetry from satellites such as ICESat provides high-resolution data for remote parts of the Earth, such as Antarctica and Greenland. Due to the large amount of data that must be processed to determine multi-temporal height variations, algorithm optimization is crucial. Modelling satellite tracks as great circle arcs on a sphere allows the application of vector algebra and spherical trigonometry in searching crossovers and near-shots for height variation analysis. Two programs written in Fortran 90/95 are presented: the former reads and filters ICESat data from input GLA12 binary files, while the latter implements the search for multi-temporal height variations. The analysis of inter-annual height variations in a megadune field of East Antarctica shows decimetre-scale changes possibly related to wind-driven accumulation and erosion processes.