Towards physical habitat characterisation in the Antarctic Sor Rondane Mountains using satellite remote sensing

• Published in: Remote Sensing Applications: Society and Environment
• Main Authors: Vanhellemont, Quinten, Lambrechts, Sam, Savaglia, Valentina, Tytgat, Bjorn, Verleyen, Elie, Vyverman, Wim
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2021
• Subjects: Biology and Life Sciences; DIGITAL ELEVATION MODEL; LANDSAT; ICE; SURFACE; AREA; RADIATION; ECOSYSTEMS; THICKNESS; IMAGERY; SYSTEM; Antarctica; Ice-free regions; Digital surface model; Land surface; temperature; Pleiades; Landsat 8; Antarctic; East Antarctica; Perlebandet; Sor Rondane Mountains; Sor-Rondane; The Antarctic; Utsteinen; Antarc*; Ice Sheet
• Online Access: https://biblio.ugent.be/publication/8734916; http://hdl.handle.net/1854/LU-8734916; https://doi.org/10.1016/j.rsase.2021.100529; https://biblio.ugent.be/publication/8734916/file/8750002

Ice-free areas occupy less than 0.25% of the Antarctic surface, and mainly occur along coastlines, or as inland nunataks protruding from the extensive ice sheet. Their extreme environment and geographical isolation have contributed to the evolution of highly adapted, and largely endemic terrestrial biota. Physical habitat mapping is important to identify the main drivers of spatial variation in soil biodiversity, to predict its response to climate change and to help conservation planning. In this paper we retrieved remotely sensed Land Surface Temperature (LST) and Digital Surface Models (DSM) for the Sor Rondane Mountains in East Antarctica from respectively the Thermal InfraRed Sensor (TIRS) on Landsat 8 and the Pl eiades constellation of high resolution optical imagers. Satellite data were combined with ground truth temperature and elevation measurements with the aim to assess the performance of these remotely sensed data. Over a 2 year period, satellite derived LST corresponded to in situ temperature with Mean Average Difference (MAD) of 2.5 K, and Root Mean Squared Difference (RMSD) of - 6.3 K. Lower biases were observed for periods when the data loggers were frozen or snow covered (MAD 1.8K) compared to intervals where the devices were not frozen (MAD 4 K), with larger scatter (RMSD 7 K) being observed during the latter. These larger MAD and RMSD are caused by the differential heating of the top of the gravel/rocks as observed by the satellite compared to their underside, where the loggers were installed, and are also impacted by the time step of the in situ logging (3 h) and the non-linear heating of the surface. In addition, for the different study sites different biases were observed as a result of the spatial resolution of the TIRS, depending on the composition, structure, geomorphology, and the surroundings of the logger position. Sites on a narrow rock outcrop (e.g. the Perlebandet and Utsteinen nunataks) show a negative bias due to the surrounding ice fields decreasing the satellite pixel average ...