The successive ice separations ... a new threat to the warming world

Asia Dia

On the evening of August 5, 2013, a terrible accident occurred in a remote location within the largest national park in the United States. Suddenly, a snowy tongue - half a kilometer in length - separated from a small glacier in Alaska, and the tongue crawled sweeping with its rocks.

Then, a torrent of snow and rocks set off - on a 11-km journey - towards the Rangel Sant Elias National Park and Reserve, but fortunately, its rugged mountain valley surrounded the park.  

Important to probe the depths
Two years later, this incident was repeated in the same place, and then the geologist in the reserve Michael Losso decided to explore the depths of these two incidents.

"Initially, we imagined that these torrents occurred as a result of landslides, but we discovered that all the ice had disappeared," says Michael.

To explore what happened at the glacier, Lusu, Jacquemart and other experts used satellite images and field measurements, and used digital elevation models and meltwater determination models.

They published their studies in the journal "Geologist" on April 27th, in which they indicated that the Alaskan avalanche occurred at the height of the summer, which means that these accidents will recur as the global warming crisis worsens.

"This mission was a huge challenge for us ... Finally we were able to solve the mystery of the separation of the ice tongue. We discovered an ice bulge on the glacier," says Jacquemart.

Snow Bulge
Although researchers were aware of the presence of the snow bulge since 2013, they did not realize its consequences at that time. The satellites took pictures of the bulge 10 years ago, and the pictures showed that it was high altitude, as it reached 70 meters in length, and therefore the reasons for the separation of the tongue were revealed. Glacier.

To clarify the sequence of events, Jacquemart says, "The search results revealed that the bottom of the snow tongue was very thin and very frozen, and we think he was responsible for two things: the first was to reserve the falling snowfall into the valley until it accumulated and formed an ice bulge, and the second that it slowed the process of leaking snow water The melt, which caused the water to take ice from the houses. These two things resulted in high water pressure, which led to the sudden collapse of the tongue. "

It showed that "the disappearance of the ice occurred as a result of its melting rapidly, and researchers should try to understand the new melting mechanism, in order to predict possible dangers in mountainous areas."

A risk that may recur.
Jacquemart pointed out that the authors of contingency plans must consider the successive hazards that may result from the ice separations, as torrential snow can travel long distances, so the accident starts from a remote area and ends up in populated areas.

Separations occurred in the glaciers of Russia, Argentina and Tibet, and unfortunately, many people were killed. In Alaska, two ancient forests over 400 years old were covered in landslides, covering an area of ​​3 km2 without casualties.

"The crisis of global warming has exacerbated the severity of the ice breaks, and the meltwater formed by the summer heat may cause natural disasters that we cannot expect, and I hope that this research will be the first relief," she concluded.