Project Details
Projekt
SEHAG – Projections of Glacier-Climate Interaction: Attribution of Uncertainties
Applicants
Dr. Inga Labuhn; Professor Dr. Ben Marzeion
Subject Area
Physical Geography
Atmospheric Science
Atmospheric Science
Term
from 2018 to 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 394200609
This subproject is part of the DFG Research Unit “Sensitivity of high Alpine geosystems to climate change since 1850” (SEHAG). The second phase of SEHAG, which is applied for here, will focus on future developments in the geosystem up to 2050, exemplarily in three catchments south and north of the main Alpine ridge, Horlachtal, Kaunertal and Martelltal. In the coming decades, the expected dependency of atmospheric conditions on future greenhouse gas emissions is still low, but the geosystem response to climatic change has already led to irreversible changes, e.g., in the cryosphere. In this context, subproject 1 will provide temporally and spatially highly resolved atmospheric data, created from an ensemble of dynamically downscaled climate projections using different global and regional climate model simulations, and different emission scenarios. These data are the starting point for model-based analyses of future changes in the cryosphere and hydrosphere, as well as their consequences for soil and vegetation dynamics, geomorphological processes and sediment transport in the Alpine geosystem. The models of the respective subsystems are calibrated with the comprehensive database of field observations and reconstructions from 1850 to present day acquired in the first phase of SEHAG. Through the exchange of energy and mass with their surroundings, glaciers form an important link between climatic conditions and the terrestrial alpine environment. Understanding future glacier evolution is therefore of great relevance for assessing the climate change impact on the Alpine geosystem. For projecting glacier change, we need to rely both general circulation models and on numerical models of glaciers. The objective of subproject 1 is to create an ensemble of catchment-scale glacier change projections in the SEHAG study areas for the period 2021 to 2050. Based on this ensemble, we will quantify the uncertainty in the projections of glacier change, and isolate the contribution of specific sources of uncertainty – such as the different kinds of model shortcomings, unknown future emissions, or internal climate variability – to the overall uncertainty. This will allow us to quantify the predictability of glacier change on the catchment scale. With our detailed and thorough analysis of the structure of the different types of uncertainties, we expect to be able (i) to quantify the confidence we can have in glacier projections, and (ii) to identify potential pathways for reducing uncertainty and therefore improve glacier projections. The quantification and fine-grained attribution of uncertainty to different sources allows to investigate the signal-to-noise ratio of anthropogenic climate change at the beginning of the process chain of geosystem dynamics studied in SEHAG.
DFG Programme
Research Units
