Definition of a methodology to map the suitability of mountain glaciers for ice core drilling using morphometric and climatic indicators.

Mountain glaciers and non-polar ice core are very important sources of paleo-proxy data which are essential to achieve a complete overview of climate change in the last centuries. The glaciers melting, which rapidly increased in the last years, could lead to loss information affecting the possibility to predict how the climate will evolve. In this context, the need to develop a methodology to identify the suitable glaciers for ice core drilling is a current challenge. In the framework of the NextData project a method for mapping suitable areas at global scale has been defined by exploiting morphometric and physical parameters. The criteria governing the choice of a drilling site were identified according the literature of ice cores and by exploiting experts knowledge. Selected criteria mainly concern: i) the quality of glaciological reconstruction, ii) the technical feasibility and logistics, iii) the climatic interest. The suitability of mountain glaciers for ice core drilling is herewith defined as the probability to drill a glacier to retrieve an ice core with preserved stratigraphic information and high temporal resolution. Ice core drilling sites (from Ice core Data Base created by Geomatic Laboratory, DISAT UNIMIB) both for European Alps (n = 23) and Himalayan (n = 39) were initially overlaid on the Digital Elevation Model (DEM) and global inventories of glacier (i.e. GLIMS and RGI). Several geo-morphometric indicators (e.g. slope, flow accumulation, local relief, etc.) were then extracted from the ASTER GDEM (30 meters spatial resolution). Both for drilling site and glacier area, the cumulative distribution function was represented and classified. A weighting scheme was defined using both a data- and knowledge-driven approach in order to estimate a suitability of drilling based upon geo-morphometric indicators. Results are currently integrated with climatic record (e.g. temperature, precipitation) and accessibility indicators in order to produce a mid-latitude glaciers map of suitability for ice drilling