Ice-sheet Melting

Home
/
Current Affairs
/
Ice-sheet Melting

Ice-sheet Melting

News: According to a recent study, the melting of the ice sheet in Western Antarctica is unavoidable, no matter how much carbon emissions are cut.

What is Ice Sheet? What is the consequence of Ice sheet melting in West Antarctica?
• An ice sheet is a mass of glacial ice. The ice sheet covers more than 50,000 square kilometres of land.
• There are two major ice sheets in the world Today-Greenland ice sheet and Antarctica ice sheet. Together, they contain about two-thirds of all the freshwater on Earth.
• The ice sheet melting would result in global mean sea level rise of 5.3 metres.

How is Ice sheet different from Sea ice?

Ice Sheet	Sea Ice
Ice sheets are massive bodies of glacial land ice, extending more than 50,000 square kilometers (20,000 square miles)	Sea ice forms from the freezing of ocean water.
They form from countless layers of snow and ice that collect over thousands of years	It is a sheet of ice floating on the sea, with nothing under it
Ice sheets are found on land and can be labelled as ice caps	Unlike glaciers and ice sheets which form on land, sea ice forms, grows, and melts in the ocean
They are so massive that they move under their own weight, flowing downhill like a very slow rive	Sea ice extent changes on a yearly basis, expanding in winter and declining somewhat every summer. By reflecting the sunlight, sea ice helps keep the polar territories cool.

Why is Antarctica Ice sheet melting?
• It is primarily due to Global warming.
• Shifting Winds: Global warming has caused a shift in wind patterns that are ultimately bringing more warm ocean water into contact with the region’s ice.
• Basal Melt: Research has identified so-called “basal melt” as the most significant driver of Antarctic ice loss. Basal melt refers to the melting of ice shelves from underneath, and in the case of Antarctica, interactions with the ocean are thought to be the main cause.
• Warming of Earth’s Surface and Ocean: The ice sheets of Antarctica are losing ice due to the ongoing warming of Earth’s surface and ocean.

What are the consequences of Ice sheet melting?
• Sea Level Rise: The melting of Greenland and Antarctic ice sheets are the largest contributors of global sea level rise.
• Increase in Coastal erosion and storms: The rising sea levels lead to coastal erosion like receding beach area of Maldives. The warming of air and ocean temperatures, create more frequent and intense coastal storm surges like hurricanes and typhoons.
• Altered Ocean Circulation: Changes in the volume of melted ice entering the ocean can alter ocean currents, which in turn can affect global climate patterns.
• Thawing Permafrost: Melting ice sheets can lead to thawing permafrost, potentially enhancing natural emissions of carbon dioxide and methane to the atmosphere.
• Declining Coverage of Sea Ice and Snow: This can affect marine and ground transportation across the Arctic.
• Effect on coastal wildlife- With the melting of ice sheets, wildlife like walrus are losing their home and polar bears are spending more time on land. This has resulted in higher rates of conflict between people and bears.

Way Forward
• Reduce Greenhouse Gas Emissions
• Strict adherence to the Antarctic Treaty and Paris Agreement
• Work on solutions to slow down Melting of ice sheet (Geo-engineering techniques)
• Building infrastructure that can withstand rising sea levels and extreme weather events is crucial.