Articles | Volume 8, issue 2
23 Nov 2016
 | 23 Nov 2016

Using ground-penetrating radar, topography and classification of vegetation to model the sediment and active layer thickness in a periglacial lake catchment, western Greenland

Johannes Petrone, Gustav Sohlenius, Emma Johansson, Tobias Lindborg, Jens-Ove Näslund, Mårten Strömgren, and Lars Brydsten

Abstract. The geometries of a catchment constitute the basis for distributed physically based numerical modeling of different geoscientific disciplines. In this paper results from ground-penetrating radar (GPR) measurements, in terms of a 3-D model of total sediment thickness and active layer thickness in a periglacial catchment in western Greenland, are presented. Using the topography, the thickness and distribution of sediments are calculated. Vegetation classification and GPR measurements are used to scale active layer thickness from local measurements to catchment-scale models. Annual maximum active layer thickness varies from 0.3 m in wetlands to 2.0 m in barren areas and areas of exposed bedrock. Maximum sediment thickness is estimated to be 12.3 m in the major valleys of the catchment. A method to correlate surface vegetation with active layer thickness is also presented. By using relatively simple methods, such as probing and vegetation classification, it is possible to upscale local point measurements to catchment-scale models, in areas where the upper subsurface is relatively homogeneous. The resulting spatial model of active layer thickness can be used in combination with the sediment model as a geometrical input to further studies of subsurface mass transport and hydrological flow paths in the periglacial catchment through numerical modeling. The data set is available for all users via the PANGAEA database, doi:10.1594/PANGAEA.845258.

Short summary
This paper presents data and resulting models of spatial distributions of maximum active layer thickness and sediment thickness and their connection to surface vegetation and topography from the Kangerlussuaq region, western Greenland. The data set constitutes geometrical information and will be used in coupled hydrological and biogeochemical modeling together with previous published hydrological data (doi:10.5194/essd-7-93-2015, 2015) and biogeochemical data (doi:10.5194/essd-8-439-2016, 2016).