A GIS tool for automatic calculation of glacier equilibrium-line altitudes

A toolbox for the automated calculation of glacier equilibrium-line altitudes (ELAs) using the Accumulation Area Ratio, Area-Altitude Balance Ratio, Area-Altitude and Kurowski methods is presented. These are the most commonly-used methods of ELA calculation in palaeo-glacier reconstructions. The toolbox has been coded in Python and runs in ArcGIS requiring only the reconstructed surface of the palaeo-glacier (a DEM) as input. Through fast and automatic calculation this toolbox simplifies the process of ELA determination and can successfully work both for a single glacier and for large datasets of multiple glaciers. We describe Equilibrium Line Altitude calculation methods for palaeoglaciers.We examine suitability of each method for different glacier types.We present a toolbox for automatic ELA calculation on AAR and AABR methods.Toolbox is coded in Python and runs in ArcGIS.Toolbox use and operation are described.

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