Changes Experienced By Glaciers And Ice Caps

Climate Change

Climate change is the leading cause of changes in the mass of ice cover over the earth’s surface. This process of climate change affecting ice cover is natural as is evident from the geological time scale.

There have been numerous warm periods—as when the dinosaurs were alive—and many cold ones, like the most recent ice age, which lasted for around 20,000 years. A large portion of the northern hemisphere was covered in ice and glaciers during the last ice age.

However, at present, this change is more prominent due to anthropogenic activities such as agriculture, industrialization, carbon emissions, deforestation, vehicular emissions, etc causing global warming.

Other Important Changes

• Greenland ice sheet- lost ice mass at an average rate of 278 billion tonnes every year between 2006 and 2015(IPCC report). Also, another phenomenon is called zombie ice, which does not accumulate fresh snow even while continuing to be part of the parent ice sheet.
• Antarctica’s Melting Ice – for ex: Doomsday Glacier also known as The Thwaites Glacier is 120 km wide at its widest point, moving quickly, and melting rapidly over time.
• Thawing of Permafrost regions – Permafrost is a permanently frozen layer on or under Earth’s surface. It consists of soil, gravel, and sand, usually bound together by ice. Permafrost usually remains at or below 0°C (32ºF) for at least two years. Permafrost can be found on land and below the ocean floor. According to a recent study, an additional 1.5 million square miles of permafrost may eventually disappear for every 1.8°F (1°C) of warming.
• Changes in glacial landforms such as an increased number of glacial lakes, moraines, glacial till, etc.

Impact Of Melting Glacier And Ice Caps

Impacts

• Sea Level Rise– for ex: Thwaites glaciers’ melting already contributes 4% annually to the rise in sea level causing storm surges and coastal erosion, coastal storms like hurricanes and typhoons brought on by warming air and ocean temperatures.
• Change in Weather patterns – Because of modifications to the jet stream brought on by a combination of warming air and ocean temperatures in the Arctic and the tropics, the polar vortex is surfacing outside of the Arctic more regularly. This is due to the change in circulations in oceans brought about by melting Antarctic and Greenland Ice.
• Loss of wildlife habitats as glacier mountains are home to critical species such as snow leopards, polar bears, etc.
• Depleting sources of freshwater as many major glaciers feed the headstreams of major rivers. In the Himalayan, for example, the Ganga River, Yamuna River, and Indus River are all fed by glaciers such as Gangotri and Yamunotri.
• Increased incidents of floods and Glacial Outbursts due to increasing water influx lead to loss of life and property.
• Loss of livelihood especially in coastal areas due to coastal erosion, submergence, increased storm surges due to sea level rise
• Impacts of Permafrost Thawing –
• Increasing incidents of Viruses and Bacteria- The potential danger was highlighted by a 2016 anthrax epidemic in Siberia that was connected to a decades-old reindeer carcass revealed by melted permafrost.
• Thawing of frozen soil – recommences the decomposition process of dead organic matter that was earlier paused due to the freezing of dead plants and animals which results in the emission of greenhouse gases.