San Vito Landslide: 'Made in Florence' Radar Monitors Croda Marcora

FInterferences – Following the debris flow at the beginning of July, this morning the Civil Protection Center of the University of Florence installed an interferometric radar in the municipality of San Vito di Cadore (Belluno) to monitor the summit of Croda Marcora.

It's a system that creates "maps by monitoring approximately one million points, where the displacement is measured for each point." In practice, "it produces maps of ground displacement. And we aimed it at Croda Marcora, the hill overlooking the Alemagna state road."

Nicola Casagli, geologist and president of the University of Florence center, explains this to Agenzia Dire. This center is one of the centers of expertise of the National Civil Protection Agency, tasked with monitoring the situation and providing support to the Veneto Region and the mayors.

The debris flow that invaded the road was triggered by a series of large rock collapses. So, if the rock doesn't collapse and it doesn't rain, the road is reasonably passable.

However, observes the scientist, who is also president of the OGS (the National Institute of Oceanography and Experimental Geophysics) and a member of the major risks commission that supports the Civil Protection, "if there are collapses it is necessary to detect them before" the detachment, since these "can reactivate the lava flow that could reach the road."

In practice, the radar, by mapping the movements of the ground, can trigger an early warning of new landslides that could affect the service precisely for this reason and this is not enough, given that it is also necessary to monitor the landslide itself", which is the responsibility of the Province.

The mudslide that could reach the road, Casagli continues, "can be reactivated by large landslides, and we monitor those. Or by short, intense rainfall, and those are detected by the regional meteorological network of Arpav and by ground instruments deployed by the Province." As for the current state of play, predicting what will happen from now on "is very difficult to say."

However, the fact that so many events occurred in just a few days, in such a short period of time, is somewhat concerning. I mean, debris flows have been occurring in that area ever since the mountain existed and the road was built. However, so many events so quickly within a couple of weeks, first in Cancia, then in San Vito, and again in the canal next to the one where the first debris flow occurred in San Vito, is perhaps a slightly unusual situation compared to the past.

A situation, he adds, "undoubtedly attributable to the high temperatures that cause the temperature range, that is, large temperature variations between day and night. The rock above heats up significantly during the day and then cools at night," triggering "a phenomenon called thermoclasticism.

landslide. The rock, in practice, is slowly breaking due to temperature variations. Along with this, "in the upper section there's also the problem of melting ice, what's left of the winter: there's a lot of water and waterfalls, as we saw with the drone. Croda Marcora is therefore exposed both to this temperature variation and to the presence of a lot of water linked to melting ice and rainfall. It's certainly not a good situation, it needs to be monitored."