Ледник Перито-Морено: Величие Патагонии и вызовы изменения климата

Glacier located in the Patagonian Andes

The Perito Moreno Glacier (Lang es) is a glacier located in Los Glaciares National Park in southwest Santa Cruz Province, Argentina, and originated in the Magallanes Region in Chile. It is one of the most important tourist attractions in the Argentine Patagonia. The ice formation, in length, is one of 48 glaciers fed by the Southern Patagonian Ice Field located in the Andes system shared with Chile which has a small part of the origins of the glacier. This ice field is the world's third largest reserve of fresh water. The Perito Moreno Glacier, located from El Calafate, was named after the explorer Francisco Moreno, a pioneer who studied the region in the 19th century and played a major role in defending the territory of Argentina in the conflict surrounding the international border dispute with Chile.

Since 2020 the glacier has been retreating on its northern front, possibly due to climate change. It was previously one of the few unusual glaciers that maintained a state of equilibrium during the late 20th and early 21st centuries because it was accumulating mass at a rate similar to that of its loss. The reason for its unusually long period of stability remains debated by glaciologists. The terminus of the Perito Moreno Glacier is wide, with an average height of above the surface of the water of Argentino Lake, in Argentina. It has a total ice depth of .

Pressure from the weight of the ice slowly pushes the glacier over the inner fjord of Lake Argentino reaching the coast of Península de Magallanes and bisecting the lake at an area called the Brazo Rico (Rico Arm) on one side and the Canal de los Témpanos (Iceberg Channel) on the other. With no outlet, the water level on the Brazo Rico side of the lake can rise by as much as 30 meters above the level of the main body of Argentino Lake. Intermittently, the pressure produced by the height of the dammed water breaks through the ice barrier causing a spectacular rupture, sending a massive outpouring of water from the Brazo Rico section to the main body of Lake Argentino and the Santa Cruz river. As the water exits Brazo Rico, the scored shoreline is exposed, showing evidence of the height of the water build up. This dam–ice bridge–rupture cycle recurs naturally between once a year to less than once every decade. The glacier advances between June and December and recedes between December and April. The formation of an ice barrier is a complex process, since there is a feedback mechanism between the glacier and the lake, which affects the oscillations of the position of the glacial front in a fairly stable way. Different behaviors have been observed during the filling and in the processes of discharge of the water, which have been classified into three types: sudden, progressive and minor burst. In a sudden type event, the maximum discharge can reach 8000 m³ per second, while a smaller event only evacuates 123 m³. 2018 The front of the glacier began to move towards the opposite bank at the end of the 19th century. In 1899 it was 750 meters from the Magallanes peninsula. In the first five years of the twentieth century it continued its progression, managing to close its arm for the first time in 1917, followed by the first break.

In the 21st century, the events of 2004, 2006, 2008 and 2012 are classified as sudden download events. and discharge flow peak had a value of 5000 m³ / s, finishing with matching lake levels after four days. It was estimated that 10,000 tourists watched this event. A large visitor centre at the site features a walking circuit which allows visitors to view the southern flank and the east facing edge of the glacier. In recent years, trekking tours on the ice have gained popularity. The two standard tours are a "mini trekking" option, consisting of a short walk of about an hour and a half, and a "big ice" version, which is usually about five hours. Tour companies generally provide crampons to customers. As the Zone closes to the public during the night after 8 pm on some occasions the ice bridge collapses without spectators, as happened in the event of March 11, 2018. Also called "the pearl of the Andes" or "dragon of Patagonia" is a kind of plecoptera of the family Gripopterygidae that inhabits the Patagonian glaciers in Argentina and Chile, spending its entire life on the ice. It measures approximately and feeds on bacteria that live on the ice brought by the wind. It was found on the Upsala Glacier and described by Aubert Willink in 1956. Due to its rarity, small size, and extreme habitat, they believed it had become extinct. However, it was rediscovered in 2001 in a Torres del Paine glacier in a 20 m deep recess; on this occasion, it was named by the crew as "Patagonian dragon".