Ice Elevation Change Based on GNSS Measurements along the Korth-Traverse in Southern Greenland

• Published in: Applied Sciences
• Main Authors: Thomas Hitziger, Luisa Näke, Karel Pavelka
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2022
• Subjects: Greenland ice sheet; monitoring; GNSS; expedition; Jakobshavn Isbræ; Helheim Glacier; Technology; T; Engineering (General). Civil engineering (General); TA1-2040; Biology (General); QH301-705.5; Physics; QC1-999; Chemistry; QD1-999; Greenland; Ilulissat; Tasiilaq; Disko Bay; glacier; Ice Sheet; Jakobshavn; Jakobshavn isbræ
• Online Access: https://doi.org/10.3390/app122312066; https://doaj.org/article/c4347fed29364f38a44cb05e2c960587

In 1912, a Swiss expedition led by meteorologist Alfred de Quervain crossed the Greenland ice sheet on a route from Disko Bay to Tasiilaq. Based on that, in 2002, a series of geodetic expeditions carried out by W. Korth and later by T. Hitziger began along the same traverse as in 1912, with the last measurements taken in May 2021. The statically collected GPS/GNSS data provide very accurate elevation changes at 36 points along the almost 700 km long crossing over a period of 19 years. According to this, there is a maximum increase of 2.1 m in the central area and a decrease of up to 38.7 m towards the coasts (influence Ilulissat Isbræ). By using kinematic GNSS measurements, there is a very dense profile with a spacing of a few meters. The comparison of those measurements is performed using crossing points or minimum distances and gives equivalent results for both methods. It is shown that local ice topography is preserved, and thus gaps in data sets can be caught. Areas of accumulation and ablation on the ice sheet can be identified, showing the widespread influence of outlet glaciers up to 200 km. The data can be used for direct verification of altimetry data, such as IceSat. Both IceSat elevations and their changes can be compared.