Between 25-30 years the Marmolada glacier in the Dolomites could disappear altogether. In a decade, from 2004 to 2015, it has undergone a reduction in volume of 30% and in an area of 22%. To outline the scenario, through two 3D models, researchers of the Cnr-Ismar and of the Universities of Trieste, Genoa and Aberystwith (Wales) and of ARPA Veneto.
The study, which was given a preview last August, was published in Remote Sensing of the Environment. "Even if the temperature remains as it is, its destiny appears however marked".
Whether the fate of the Marmolada glacier is marked depends on the fact, explains Renato Colucci of the Cnr-Ismar "that it is already in total disequilibrium with the current climate". With regard to the scenarios from now on, the first relief, underlines Colucci "was acquired using a terrestrial ground penetrating radar (GPR), a non-invasive technology used in geophysics, based on the reflected electromagnetic signal transmitted from the ground to depending on the characteristics, creating detailed sections. The second, instead, using data collected in flight with helicopter Gpr ".
In this way it was possible to reconstruct two 3D models of the glacier "that allowed us to accurately measure not only the internal and morphological characteristics, but also the recent evolution over the decade, quantified in volumetric terms", continues the expert. The glacier, once a unique glacial mass, is now fragmented and divided into various units, where at different points underlying rocky masses emerge, the researchers note.
Karst soils, such as the Marmolada, are irregular and consist of bumps and hills. If the ice melts gradually, the areas in relief emerge, becoming sources of heat inside the glacier itself. "This aspect, combined with the change of albedo (snow and ice are white and reflect a lot of solar radiation, while the darker rock reflects less) - adds Colucci - is further undermining the 'health' of the Marmolada by accelerating the already strong and rapid fusion ".
The research has also shown that, if the reduction rate continues at the same pace as in the decade analyzed, "in the next 25-30 years the glacier will have practically disappeared", leaving only the small ice and snow cover. "The ice will therefore no longer exist. And if, as in climate scenarios, the temperature in the coming decades should increase at a more accelerated rate, this forecast could even be underestimated and the disappearance of the glacier could occur even more quickly", concludes the study of the Cnr.