In search of potential case study glacier sites
2018-summer field season was dedicated to finding the most optimal case study sites for our glaciological research that is planned for the 2019-field season. The field investigation took place in the European Alps, where currently 3892 glaciers still exists, covering approximately 2100 km2 (according to the data from the Randolph Glacier Inventory v. 6.0). More than 80% of the total number of glaciers in the European Alps are the so-called very small glaciers, having a surface area smaller than 0.5 km2. Although small in size, they are a relevant component of the Alpine cryosphere and widely considered as important indicators of climate change.
Distribution of all glaciers in the European Alps according to Randolph Glacier Inventory v. 6.0
Five main watersheds originate from the European Alps according to Ecrins data: the Rhine, Rhone, Danube, Po and the watershed of the Eastern Alps. Our field trip took place in the Eastern Alps watershed, where almost 20% of the glaciated area overlies carbonate rocks according to the global lithological map – GLiM (while in the entire Alpine region the glaciers overlying carbonate lithologies account for only 6% of the total glaciated area).
Distribution of glaciers (according to Randolph Glacier Inventory v. 6.0) and carbonate sedimentary rocks (according to GLiM) in the watershed of the Eastern Alps. The field sites we visited in the summer 2018 are marked with red square.
But why exactly are we interested in glaciers resting on carbonate rocks? On these glaciers, a component of the meltwater is drained by the underlying karst system, which has effect on glacier motion and the relative contribution of glacier melt to stream runoff. By collecting ice thickness, sliding/surface velocity and hydrological data from glaciers overlying bedrock of different permeability, we are trying to understand better the geologic influence on glacial hydrology, which is essential for making more accurate predictions of overall glacier response to climate change.
We visited two mountain ranges in the Italian Alps: the Dolomites, which are dominated by glaciers resting on carbonate rocks, and Vedrette di Ries / Rieserferner, where glaciers overlying non-carbonate lithologies prevail.
The Marmolada glacier, the largest glacier of the Dolomites, covering an area of approximately 1.5 km2 in 2015. The glacier rests on grey massive limestone.
The Marmolada glacier, view from Punta Penia (3343 m asl) – the highest summit of the Marmolada mountain group. Almost the whole glacier area was in the ablation zone in August 2018. Photo courtesy: R.R. Colucci
The Westlicher Rieserferner – Vedretta di Ries Occidentale glacier is the largest glacier of the Vedrette di Ries / Rieserferner mountain range. The glacier area in 2015 was about 1.7 km2. Glacier overlies igneous and metamorphic rocks. Photo courtesy: R.R. Colucci
A very thin ice at the terminus of the Westlicher Rieserferner – Vedretta di Ries Occidentale glacier.