Parque Nacional Los Glaciares
Parque Nacional de Los Glaciares is Argentina’s second largest national park and forms part of South America’s Patagonia region. It covers an area of 726,927 hectares (1,796,212 acres). It was established in 1937 and was declared a UNESCO World Heritage Site in 1980.
The park’s name refers to the giant ice cap in the Andes range, which occupies almost half the park’s area, and which feeds 47 glaciers. The ice cap is the largest outside Antarctica and Greenland. Due to the size of the ice cap the glaciers begin at an unusually low height of 1,500 metres (4,900 ft) flowing down to 200 metres (660 ft).
The park is in two sections, each centred around a large lake. In the northern part is Viedma Lake, the Viedma Glacier and a few smaller glaciers, and a number of mountains including Mount Fitz Roy and Cerro Torre. In the south are the major glaciers which flow into Lake Argentino: Perito Moreno Glacier, Upsala Glacier and Spegazzini Glacier, the two latter are only accessible by boat.
Perito Moreno is the largest and most famous of the glaciers. It is 250 square kilometres (97 sq mls) and 30 kilometres (19 mls) in length, and growing. Its terminus is 5 kilometres (3 mls) wide, with an average height of 74 metres (240 ft) above the surface of the water of Lake Argentino. It has a total ice depth of 170 metres (558 ft). The calving of ice bergs, as ice falls from its front walls, is spectacular to witness.
As the glacier ice advances into the lake it forms a dam wall separating part of the lake, the Brazo Rico, from the main lake. Water in the Brazo Rico can consequently rise up to 30 metres (98.5 ft) above the level of the main lake. Every few years the pressure from the water in the upper section becomes so great that the ice ruptures allowing for a thunderous out-rushing of water. The lakes are shared by many water birds including black-necked swans, a variety of ducks and geese, and flamingos.
Lenticular clouds can occasionally be seen in the skies over the mountains. These unusual clouds are, as the name suggests, lens shaped. They are quite regular in their outline, without displaying the fluffy clumps or streamers of more common clouds. Most often they form into stacks, giving an appearance similar to a pile of pancakes. Sometimes they have been confused with UFOs. They are almost stationary and bring little or no rain.
To the east of the icy mountains lies the arid Patagonian steppe. This is a landscape of tablelands, massifs, and canyons. Most of the vegetation here is grasses, shrubs and small herbaceous plants. The region is home to rheas, large flightless birds related to emus and ostriches. Condors and eagles can also be seen. Animals include guanaco, cougar and grey fox.
Between the ice and the Patagonian steppe there is a fertile area of Magellanic subpolar forests of various species of Southern beech which turn the area into a scene of dramatic colour in autumn. These are the world’s southernmost forests. They provide a habitat for the native huemul deer and torrent duck.