Validation of satellite altimetry by kinematic GNSS in central East
Ludwig Schröder1, Andreas Richter1, Denis V. Fedorov2, Lutz Eberlein1, Evgeny V. Brovkov2, Sergey V. Popov3, Christoph Knöfel1, Martin Horwath1, Reinhard Dietrich1, Alexey Y. Matveev2, Mirko Scheinert1, and Valery Lukin41Technische Universität Dresden, Institut für Planetare Geodäsie, Dresden, Germany 2OAO Aerogeodeziya, St. Petersburg, Russia 3Polar Marine Geosurvey Expedition (PMGE), St. Petersburg, Russia 4Arctic and Antarctic Research Institute (AARI), St. Petersburg, Russia
Received: 07 Dec 2016 – Accepted for review: 14 Dec 2016 – Discussion started: 03 Jan 2017
Abstract. Ice-surface elevation profiles of more than 30.000 km in total length are derived from kinematic GNSS observations on sledge convoy vehicles along traverses between Vostok station and the East Antarctic coast. The profiles have accuracies between 4 and 9 cm. They are used to validate elevation datasets from both radar and laser satellite altimetry as well as four digital elevation models. A crossover analysis with three different Envisat radar altimetry datasets yields a clear preference for the relocation method over the direct method of slope correction and for threshold retrackers over functional fit algorithms. The validation of Cryosat-2 low-resolution mode and SARIn mode datasets documents the progress made from baseline B to C elevation products. ICESat laser altimetry data are demonstrated to be accurate to a few decimeters over wide range of surface slopes. A crossover adjustment above subglacial Lake Vostok combining ICESat elevation data with our GNSS profiles yields a new set of ICESat laser campaign biases and provides new, independent evidence for the stability of the ice-surface elevation above the lake. The evaluation of digital elevation models reveals the importance of radar altimetry for the reduction of interpolation errors.
Schröder, L., Richter, A., Fedorov, D. V., Eberlein, L., Brovkov, E. V., Popov, S. V., Knöfel, C., Horwath, M., Dietrich, R., Matveev, A. Y., Scheinert, M., and Lukin, V.: Validation of satellite altimetry by kinematic GNSS in central East
Antarctica, The Cryosphere Discuss., doi:10.5194/tc-2016-282, in review, 2017.