A glacier or is a persistent body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds its ablation over many years, often centuries. Glaciers slowly deform and flow due to stresses induced by their weight, creating crevasses, seracs, and other distinguishing features. Because glacial mass is affected by long-term climate changes, e.g., precipitation, mean temperature, and cloud cover, glacial mass changes are considered among the most sensitive indicators of climate change. There are about 198,000 to 200,000 glaciers in the world.
There are many glaciers in the Antarctic. This set of lists does not include ice sheets, ice caps or ice fields, such as the Antarctic ice sheet, but includes glacial features that are defined by their flow, rather than general bodies of ice. The lists include outlet glaciers, valley glaciers, cirque glaciers, tidewater glaciers and ice streams. Ice streams are a type of glacier and many of them have "glacier" in their name, e.g. Pine Island Glacier. Ice shelves are listed separately in the List of Antarctic ice shelves. For the purposes of these lists, the Antarctic is defined as any latitude further south than 60°. There are also glaciers in the subantarctic. This includes one snow field. Snow fields are not glaciers in the strict sense of the word, but they are commonly found at the accumulation zone or head of a glacier. For the purposes of this list, Antarctica is defined as any latitude further south than 60°.
The majority of Europe's glaciers are found in the Alps, Caucasus and the Scandinavian Mountains as well as in Iceland. Iceland has the largest glacier in Europe, Vatnajökull glacier, that covers between 8,100-8,300 km² in area and 3,100 km³ in volume. Norway alone has more than 2500 glaciers covering an estimated 1% of mainland Norway's surface area. Several of mainland Europe's biggest glaciers are found here including; Jostedalsbreen, Vestre Svartisen, Søndre Folgefonna and Østre Svartisen. The two Svartisen glaciers used to be one connected entity during the Little Ice Age but has since separated.
There are a number of glaciers existing in North America, currently or in recent centuries. In the United States, these glaciers are located in nine states, all in the Rocky Mountains or further west. The southernmost named glacier among them is the Lilliput Glacier in Tulare County, east of the Central Valley of California. Mexico has about two dozen glaciers, all of which are located on Pico de Orizaba, Popocatépetl and Iztaccíhuatl, the three tallest mountains in the country.
Glaciers in South America develop exclusively on the Andes and are subject of the Andes various climatic regimes namely the Tropical Andes, Dry Andes and the Wet Andes. Apart from this there is a wide range of latitudes on which glaciers develop from 5000 m in the Altiplano mountains and volcanoes to reaching sealevel as tidewater glaciers from San Rafael Lagoon and southwards. South America hosts two large ice fields, the Northern and Southern Patagonian Ice Fields, of which the latter is the second largest contiguous body of glaciers in extrapolar regions. The glaciers of Venezuela are located in the mountains of the Sierra Nevada de Mérida. In 1910, maps made by the explorer Alfredo Jahn showed the Sierra Nevada glaciers covering about. An ice trade at that time saw ice men or hieleros transporting glacier ice by mule or on foot to Mérida for sale, a six hour journey. Venezuela's glacier coverage shrank to about in 1952, and in 1985. The last remaining glacier, located on Pico Humboldt, was estimated to cover in 2011.
Oceania
No glaciers remain on the Australia mainland or Tasmania. A few, like the Heard Island glaciers are located in the territory of Heard Island and McDonald Islands in the southern Indian Ocean. New Guinea has the Puncak Jaya glacier. New Zealand contains many glaciers, mostly located near the Main Divide of the Southern Alps in the South Island. They are classed as mid-latitude mountain glaciers. There are eighteen small glaciers in the North Island on Mount Ruapehu. An inventory of South Island glaciers compiled in the 1980s indicated there were about 3,155 glaciers with an area of at least one hectare. Approximately one sixth of these glaciers covered more than 10 hectares. These include:
Jacka Glacier - Anzac Peak - Heard Island - Indian Ocean
List of longest glaciers in world in non-polar regions
The following is the list of longest glaciers in the non-polar regions, generally regarded as between 60 degrees north and 60 degrees south latitude, though some definitions expand it slightly.