Toposcale is a downscaling tool that uses the well-resolved description of the atmospheric column provided by climate models, together with high-resolution digital elevation models (DEMs), to downscale coarse-grid climate variables to a fine-scale subgrid. The main aim of this approach is to provide high-resolution driving data for a land-surface model (LSM). Full desciption available in this publication: http://www.geosci-model-dev.net/7/387/2014/
Published here: http://www.the-cryosphere.net/9/411/2015/tc-9-411-2015.html
Fiddes, J. and Gruber, S.: TopoSCALE v.1.0: downscaling gridded climate data in complex terrain, Geosci. Model Dev., 7, 387-405, doi:10.5194/gmd-7-387-2014, 2014.
TopoSCALE is licensed under the GNU GPL license, version 3 (or later). Basically, it grants you the rights to use, redistribute and modify TopoSCALE. However, if you want to redistribute a modified version of TopoSCALE, you must provide the complete source code of your modifications.