Ice Cap
An ice cap is a type of glacier that covers less than 50,000 square kilometers (approximately 19,000 square miles) and consists of a thick layer of ice or snow. These formations typically take on a dome shape and can be found in various locations around the world, especially in polar regions where they are referred to as polar ice caps. Ice caps are vital components of Earth’s climate system, impacting sea levels and local ecosystems. The largest ice cap is located in the Russian Arctic, known as the Severny Island ice cap. Historically, significant ice caps were also found on Mount Kilimanjaro in Tanzania, but these are rapidly melting. Ice caps support a limited range of life, primarily around their peripheries, where larger animals like musk oxen and polar bears can be found, along with rich marine life beneath Arctic ice. Recent studies have shown fluctuations in the size of ice caps due to climate change, with some areas experiencing expansion in ice coverage while others, like the Austfonna in Norway, are diminishing rapidly. Understanding ice caps is crucial for assessing the impacts of global warming and predicting future changes in our environment.
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Ice Cap
An ice cap is a glacier covering less than 50,000 square kilometers or 19,000 miles. The constitution of the ice cap or glacier is that of a thick layer of ice or snow. Ice caps and glaciers connected in a series format are referred to as an ice field. Ice caps and ice fields are located worldwide and are termed polar ice caps when appearing in regions of high latitude. The shape of an ice cap is like a dome, moving outward from the center. The summit of a mountain peak surrounded by a glacier and penetrating the ice is called a nunatak. A small number of organisms are able to exist on an ice cap. The largest ice cap in the world is situated in the Russian Arctic in the Novaya Zemlya archipelago. This ice cap is named Severny Island ice cap.
Background
The accumulation of snow and its subsequent melting is a process that initiates the forming of an ice cap or glacier. Once the snow melts, it tends to compress, and the texture is harder. As the new season's snow falls on top of these hard ice pellets, the grainy snow is covered by the new snowfall. More intense densification of the hard snow occurs with increasing layers of this firn, as it is known. At a point where 50 meters (165 feet) of ice have developed, it becomes a solid ice mass.
In the past, ice caps were found on the summit of Mount Kilimanjaro in Tanzania, the highest mountain in Africa; however, the glaciers are diminishing rapidly. The Furtwangler glacier atop Mount Kilimanjaro, which measures 60,000 square kilometers (23,166 square miles) is the last ice cap remaining in Africa. Because of the speed at which the glacier is melting, there may no longer be an ice cap in this area in the future.
There are numerous ice caps in northern Europe. The ice cap Vatnajökull of Iceland covers the island by approximately 8 percent. Norway's ice cap Austfonna located in the Svalbard archipelago, is one of the largest in Scandinavia. Ice caps and ice fields are found in mountainous regions of the Himalayas, Rockies, and Andes. New Zealand also houses ice caps and ice fields in its southern alps. The Russian Arctic Severny Island ice cap is the world's largest.
An example of an ice field that arises on a seasonal basis is the Yolyn Am, situated in a gorge in Mongolia's Gurvan Saikhan range of mountains. The area falls in the Gobi Desert, a dry space where there is low precipitation. The ice field appears for a short period of time and melts by the autumn months.
Life exists around the areas of ice caps. Plant and animal life are found on the periphery of ice caps, though only a few organisms exist on the actual ice cap. Large musk ox and polar bears inhabit the Arctic ice cap locations. In the Arctic region, particularly, a rich marine life is found under the ice caps, home to seaweed and krill, as well as varieties of fish. Whales and seals live around the Arctic Circle ice caps. The Indigenous Yupik people have established viable life in coastal areas of Siberia, such as the Chukchi Peninsula, as well as Russia and St. Lawrence Island, Alaska. Marine life provides them with a source of food and other essentials required for housing and transport.
Polar ice caps are water-based ice when appearing on earth; whereas they comprise water ice and solid carbon dioxide when located on Mars.
Ice Caps Today
NASA's New Horizons spacecraft revealed features on the surface of Pluto that indicate Pluto may have a polar ice cap. A bright surface area near the pole of Pluto is the area under observation. In the flyby of July 2015, studies indicate a combination of methane and nitrogen ice in the polar cap region. NASA reports an abundance of methane ice on Pluto, and that the formation differs in different sections of the frozen surface. Nitrogen ice, with an ability to absorb infrared light, is the diluted form of methane ice found on the north polar cap. This manifests as a patch of light that is visible through photographs.
Former US Vice President Al Gore issued a warning in 2007 that there would be an Arctic meltdown. His speech to campaign for climate change awareness was given at the Nobel Peace Prize ceremony. Concerned about global warming and the effect this would have on the ice regions, Gore predicted there would be little ice left. Instead, there has been an expansion of the Arctic ice cap at a rate of 43 to 63 percent since 2012. Thus, the polar ice cap has increased rather than decreased in size. In August 2014, the measurement given for the Arctic ice bed was 5.62 million square kilometers in size. This corresponded to the 43 percent increase calculated, as well as a 1.71 million square kilometer increase, according to the US National Snow and Ice Data Center, funded by NASA. The Danish Meteorological Institute gave the higher number of 63 percent, stating that the Arctic ice cap measured 4.4 million square meters, with a 2.7 million square kilometer increase. However, after this, the Arctic ice bed began to decrease in size. By 2023, it had shrunk to 1.63 million square miles (4.23 million square kilometers).
Another ice cap that also appears to be disappearing is Austfonna, part of the Svalbard Island chain in Norway. Research scientists at the University of Leeds in the United Kingdom have reported on the state of this Arctic ice cap by analyzing satellite measurements. According to the National Oceanic and Atmosphere Administration (NOAA), as of 2023, the ice measured was 6.55 million square miles (16.96 million square kilometers). This is 676,000 square miles (1.75 million square kilometers) below its average size from 1981 to 2010.
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