The Triglav Glacier (South-Eastern Alps, Slovenia): Volume Estimation, Internal Characterization and 2000–2013 Temporal Evolution by Means of Ground Penetrating Radar Measurements

Abstract

It is well known that small glaciers of mid latitudes and especially those located at low altitude respond suddenly to climate changes both on local and global scale. For this reason their monitoring as well as evaluation of their extension and volume is essential. We present a ground penetrating radar (GPR) dataset acquired on September 23 and 24, 2013 on the Triglav glacier to identify layers with different characteristics (snow, firn, ice, debris) within the glacier and to define the extension and volume of the actual ice. Computing integrated and interpolated 3D using the whole GPR dataset, we estimate that at the moment of data acquisition the ice area was 3800 m2 and the ice volume 7400 m3.\ud Its average thickness was 1.95 m while its maximum thickness was slightly more than 5 m. Here we compare the results with a previous\ud GPR survey acquired in 2000. A critical review of the historical data to find the general trend and to forecast a possible evolution is also presented. Between 2000 and 2013, we observed relevant changes in the internal distribution of the different units (snow, firn, ice) and the ice volume reduced from about 35,000 m3 to about 7400 m3. Such result can be achieved only using multiple GPR surveys, which allow not only to assess the volume occupied by a glacial body, but also to image its internal structure and the actual ice volume. In fact, by applying one of the widely used empirical volume-area relations to infer the geometrical parameters of the glacier, a relevant underestimation of ice-loss would be\ud achieved

Quaternary glaciation in the Mediterranean mountains: a new synthesis

“…Small glaciers are present today in the mountains of Slovenia (Colucci 2016;Del Gobbo et al 2016), including on the highest peak of Triglav (2864 m Hughes 2014). The glacial record of Slovenia is still poorly dated -as noted in the review by Ferk et al (2015) in this volume -although a few ages were presented over a decade ago in Bavec et al (2004) from the glaciated Soča valley.…”

Unprecedented heat wave in December 2015 and potential for winter glacier ablation in the eastern Alps

“…In order to provide an estimate of this effect, we calculated the potential of ice melting during December 2015 at the Canin, Triglav and Sonnblick sites, where ice patches and small glaciers are present 26 , 28 – 30 , by using a degree-day factor (DDF) approach for melting snow and ice. We used a DDF for melting snow of 4.1 mm day −1 °C −1 water equivalent (w.e.)…”

“…We used a DDF for melting snow of 4.1 mm day −1 °C −1 water equivalent (w.e.) and a DDF for melting glacier ice of 7.9 mm day −1 °C, which are widely adopted to estimate ice-snow ablation at the Equilibrium Line Altitude (ELA) of glaciers in different regions of the world 28 . Note that in previous studies the DDF was calculated for the ablation season (mostly summer) and, since the DDF implicitly integrates radiation information, it may be lower for the winter.…”

Spatial and climatic characterization of three glacial stages in the Upper Krnica Valley, SE European Alps

“…The occurrence of relict thick glacier ice deposits located at similar elevations has been already reported also from other ice patches in the southeastern Alps (Carturan et al, 2014;Forte et al, 2014a), such as the case of the Prevala, the Montasio West and the Canin East. This is important because the Krnica glacier represents a much larger and thicker ice body if compared with the disappearing but iconic Triglav glacier, now reduced to a thin plate of dead ice and classified as an ice patch of glacial origin with no dynamics (Del Gobbo et al, 2016). Thick debris deposits of the Krnica ice patch have the effect of limiting the summer melting, thus slowing down a fast disappearance of such small ice bodies.…”