Mass Balance Surveys at the "Alto di Popera" Glacier, in the Sexten Dolomites, are Started

A new, important activity of monitoring, study and research for the Alpine-Adriatic Meteorological Society in cooperation with the Italian Glaciological Commitee, the Institute of Polar Sciences of the CNR and the Department of Mathematics and Geosciences of the University of Trieste, just started

The Alto di Popera glacier

The Alto di Popera glacier is the largest residual ice body of the Sesto Dolomites group. Due to the strong reduction in recent decades, it is now enclosed at the base of the walls of Cima Unidici - Elferkofel (3096 m asl) in the highest part of Vallon Popera, on the orographic right of the Sentinella Pass.

From a geomorphological point of view, the glacier has undergone a drastic reduction in its surface and mass. Today it appears almost entirely covered with debris and could be defined as a small debris covered glacier. Several transverse crevasses, in addition to the Randkluft, in fact, suggest a still weak flow dynamics.

The huge debris cover, in this climatic phase, is partially protecting the residual ice from increased summer ablation due to warmer summer seasons, triggering a resilience process already observed in other small glaciers in the Eastern Alps.

The Alto di Popera glacier in a 2017 picture highlights the presence of a debris covered over the glacial remnant.

The Survey

The Alpine-Adriatic Meteorological Society, in collaboration with the Italian Glaciological Committee, the Institute of Polar Sciences of the CNR and the Department of Mathematics and Geosciences of the University of Trieste, has decided to finance the first expedition in Vallon Popèra to bring at the end a detailed topographical survey of this (now) small residual glacial body.

The realization of a high resolution digital elevation model (DEM) will allow starting a long-term monitoring of the mass balance and the geomorphological evolution of this dolomitic glacial body Several photogrammetric surveys have been carried out which will allow in post-processing, through the technique called Structure from Motion, to obtain three-dimensional and geolocalized digital models of the terrain.

This activity is part of a wide project called "Glaciers and Permafrost in the Alpe-Adria Region" aimed at monitoring the evolution of the cryosphere of the Eastern Alps in this delicate climatic phase of global warming.

The main glacial bodies of Vallon Popera are historically 3, all on the orographic right. In addition to the Alto di Popera glacier, just below the imposing frontal moraine, there was the Basso di Popera glacier, now practically extinct apart from (perhaps) some residual ice not visible below the detrital cone fed by avalanches.

Higher up, there is the Pensile glacier, still present but largely covered by debris and probably with almost no dynamics. Until a few decades ago, the Pensile glacier was able to give life to a small regenerated glacier fed by the collapse of the seracs from its front.

Some drone images of the Alto di Popera glacier (left) and the Pensile glacier (center and right). photo Daniele Fontana

Why Matters

From the melting waters of the small glacial bodies of the Vallon Popera, the Risena stream born and, after having fed a small glacial lake (Lake Popera), and passed through an orograqphic jump (a waterfall that is now often dry), forms the main tributary of the Padola stream, which in turn it is grafted into the Piave river. Alpine glacial bodies have always been a source of important water supply not only for the valley populations, but also regulating the regime of the great rivers of the plains.

The rapid contraction and disappearance of alpine glaciers will have important consequences on the water regime of the valleys and the first effects are already part of today's news. In recent days, for example, the Quintino Sella al Monviso refuge will be forced to close the season early due to the lack of water (here the ANSA news).

These problems could soon involve many other high altitude shelters, and even Vallon Popera may not be immune to all of this. The base of support for the team that carried out the surveys on 6 and 7 September last was in fact the Berti refuge, a splendid balcony on the Comelico Superiore, of which we sincerely thank the managers for their usual warm and friendly welcome and for the excellent food. .

The Team

The team was made up of 8 people, including two students from the University of Trieste involved in the realization of their degree thesis within the curricular training internship agreement in place between the Department of Mathematics and Geosciences and the SMAA. Alberto De Luca will deal with the creation of the digital model of the Alto di Popera glacier followed by Renato R. Colucci (ISP-CNR and SMAA) as mentor and by Simone Pillon (UniTS) and Andrea Securo (SMAA) as co-mentors. Elisa Benedetti Fasil, on the other hand, will have the task of studying the complex moraine system from a geomorphological point of view and reconstructing the ELA of the glacier, always followed by Renato R. Colucci as mentor, and Costanza Del Gobbo (post Doc ICTP and SMAA ) and Lukas Rettig (Germany; UniPd PhD student) as co-mentors. To complete the team, Daniele Fontana (SMAA), who gave an important logistic contribution and organized locally the expedition, and Marco Basso Bondini (SMAA).

The team which carryed out the survey on September 6 and 7 (n.d.r. everyone with green pass)

Brief Historical Note on Vallon Popera

Vallon Popera had enormous strategic importance during the First World War and there are numerous remains of military fortifications in the area. Even today it is easy to find exploded ammunition and various remnants of war. In the early 1980s the remains of an Alpine soldier were found from the Alto di Popera glacier. The body of this unknown soldier, without an identification plate, was then buried in the shrine of Santo Stefano di Cadore and the then Head of italian Republic Sandro Pertini was also present at the funeral. In recent years it has been possible to trace the generalities of this man.

An hystorical image of Vallon Popera during World War 1 allows highlighting the strong glacier recession of the last cenbtury

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