Towards closing the gap between local scale meteorology and changing alpine glaciers
In the last few decades retreating glaciers around the world have received much attention as they are a clear and unequivocal sign of climate change. However, the discussion about climate change is often focused on changes in temperature, while other important atmospheric variables such as humidity, cloudiness, precipitation, solar irradiance and especially related feedbacks are neglected.
In fact, "climate" is the synthesis of all meteorological variables over a long period of time (typically 30 years or more). Retreating glaciers therefore are not solely responding to a warming atmosphere, but also to changes in the afore-mentioned atmospheric variables. The energy and mass balance of a glacier surface represents the most direct link between glacier change and the underlying climatic forcing. To identify and understand the climatic drivers of glacier changes, it is therefore necessary to study the physical processes behind the glacial energy and mass balance.
This project represents a first step to establish the instrumental infrastructure for such studies at Langenferner in the Ortler-Cevedale Group, Northern Italy. Langenferner is a benchmark glacier for the Autonomous Province of Bozen and the southern part of the East Alpine region. In the frame of the current project, data from several existing weather stations in the vicinity of the glacier will be used to drive a high resolution physically based mass balance model. In order to properly extrapolate the meteorological data from these off-glacier stations to the glacier surface, statistical transfer functions will be developed. Finally, the optimized mass balance model with the extrapolated off-glacier data as input will be used to model the long term mass balance of Langenferner. Measured annual mean specific mass balances and single stake ablation data will be used to validate the results of the model simulations.