Earth's Cryosphere Shrinking by 33,000 Square Miles Annually: How Does Ice Sheet Melting Impact the Planet?

Earth's cryosphere is on the verge of disappearing as a new study reveals that it is shrinking by about 33,000 square miles (87,000 square kilometers) every year from 1979 to 2016. That is an area equivalent to Lake Superior.

The study, "A Holistic Assessment of 1979-2016 Global Cryospheric Extent" published in AGU's journal Earth's Future, is the first to make a global estimate of the world's sea ice surface area, as well as the snow cover and frozen ground.

Like ordinary land, Earth's cryosphere is also essential for the world's ecosystem because it helps cool the planet by effectively reflecting sunlight. But with climate change, the size and location of ice and snow are altered and change the sea level and ocean currents.

(Photo : Pixabay)
Global Cryosphere: Study Reveals Global Sea Ice Shrank by 33,000 Square Miles Annually

Getting to Know the Earth's Cryosphere

Scientists call the Earth's frozen places the cryosphere, which comes from the Greek word for cold "kryos". These cold regions of Earth influence the entire planet's climate and are central to the daily lives of the living things that made it their home.

According to the National Ice and Snow Data Center, the cryosphere specifically describes the Earth's frozen region, and people most likely think it is at the top or bottom part of the planet, and the polar regions. The North Pole is called the Arctic, while the South Pole is called the Antarctic, both regions are comprised of ice and snow.

The Arctic has lots of sea ice and permafrost. Glaciers, ice, and snow cover the nearby lands including Greenland. Meanwhile, in the south Pole, the Antarctic is an icy continent where huge ice sheets cover the land and ocean.

But there is also ice in between the poles, like the snow that covers Mount Kilimanjaro in Africa, frozen soil in the mountains of the United States, and the northern parts of Russia, China, and Canada.

Generally, the cryosphere is the area of sea ice, glaciers, ice shelves and icebergs, and even the frozen ground. They are part of the ecosystem that is now being threatened by climate change as they slowly disappear every year. They hold most of the freshwater and their dwindling numbers could threaten the drinking water supplies.

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Shrinking Cryosphere

Although the cryosphere may grow or increase depending on the season, researchers of the new study found that the Earth's cryosphere has been shrinking since 1979 due to the rising air temperatures.

According to Phys.org, the shrinkage is mostly happening in the Northern Hemisphere which has recorded a loss of 39,300 square miles (102,000 square kilometers), or about half of Kansas every year.

Although this loss is slightly offset by the growth in the Southern Hemisphere with an estimated expansion of about 5,400 square miles(14,000 square kilometers). The growth is largely seen in the Ross Sea around Antarctica.

Moreover, it is estimated that not only is the global cryosphere shrinking but that many regions of the planet have stayed frozen for less time. For instance, researchers found that the average first day of freezing occurs about 3.6 days later than it was in 1979, and ice thaws at about 5.7 days earlier than before.

Researchers said that a global dataset is now available to use for probing the impact of climate change on the cryosphere and how it will affect the ecosystems, carbon exchange, and timing of life cycles in both animals and plants.