Ole Baltazar Andersen (Professor, Denmark)

Radar altimeters have traditioally been used for the determination of the mean sea surface to centimeter accuracy. However close to the coast the MSS degrade because of the lack of valid altimetry observations and because of the land contamination and the altimeter footprint size.
In 2018, the National Aeronautics and Space Administration launched ICESat-2, a laser altimetry mission equipped with the Advanced Topographic Laser Altimeter System, providing measurements every 0.7 m in the along-track direction. We have investigated the use of ICESat-2 around Greenland and Denmark. Greenland has a highly complex coastline and Denmark has more than 20 GNSS controlled tide gauges for validation. The aim os to investigate if we can improve coastal MSSfrom ICESat-2 for the updating of the upcomming DTU24MSS model. In Greenland we realised that the existing ocean tide model hampers the use of laser altimetry in the fjords as FES2014 does not cover. Hence we developed a novel method which simultaneous determine the tides, the MSS and the season variation in sea level.