Large Area Mountain Permafrost Simulation at DEM Resolution : Results from the European Alps and Himalaya

Abstract:

We present a system that is able to simulate land-surface conditions at continental scales while accounting for parameters that vary on order of 10's of metres (e.g., topography or surface cover) by using a statistical subgrid scheme (Fiddes and Gruber 2012). The model chain is driven by output from atmospheric datasets with a simple in-house downscaling scheme which uses only data on atmospheric pressure-levels and a DEM (Fiddes and Gruber 2014). The scheme has been tested in the case of mountain permafrost in the European Alps (Fiddes and Gruber 2015) with good results. However the strength of the scheme is application to remote data-sparse regions. Recently we have applied the scheme to simulate permafrost conditions in the Western Himalaya. This included a simple approach to correct snow mass balance using MODIS products, as input precipitation from atmospheric models may often have bias. The scheme is flexible in choice of atmospheric model input data, numerical surface model and surface data. In this abstract we will (1) present the model chain, (2) show the results of simulating permafrost conditions over large areas using only global datasets as input and (3) give an outlook to simulating future conditions.

Fiddes, J., Endrizzi, S., and Gruber, S. 2015: Large-area land surface simulations in heterogeneous terrain driven by global data sets: application to mountain permafrost, The Cryosphere, 9, 411-426, doi:10.5194/tc-9-411-2015, 2015. http://dx.doi.org/10.5194/tc-9-411-2015

Fiddes, J. & Gruber, S. 2014: TopoSCALE v.1.0: downscaling gridded climate data in complex terrain, Geoscientific Model Development, 7, 387-405, http://dx.doi.org/10.5194/gmd-7-387-2014

Fiddes, J. & Gruber, S. 2012: TopoSUB: a tool for efficient large area numerical modelling in complex topography at sub-grid scales, Geoscientific Model Development, 5, 1245–1257,http://dx.doi.org/10.5194/gmd-5-1245-2012