On July 12 scientists announced that a giant iceberg, covering an area of roughly 6,000 sq km had broken away from Larsen C, an ice shelf off the west coast of Antarctica.
The Larsen Ice Shelf, (the fourth largest in the Antarctic Peninsula) is a mass of floating ice that covers an area of 78,500 sq km. It has many segments, and they are named alphabetically. One of them is Larsen C. The ice shelf has been gradually breaking down since the mid-1990s. Larsen A and B have already disintegrated and Larsen C is the latest casualty.
A warming peninsula
Typically, ice shelves lose mass by melting at their upper and lower surfaces and iceberg calving, which is when chunks of ice break away from the edges of the shelf. There are several reasons why this happens, but many scientists think it is due to global warming.
According to a report by the Intergovernmental Panel on Climate Change, temperatures in the Antarctic Peninsula, where Larsen C is located, have been rising at four to six times the global average. This has speeded up the melting and thinning of ice shelves, making them prone to rifts that result in calving.
Following the calving, Larsen C has lost more than 12% of its area and a new rift is seen to be extending northwards, posing a serious threat to the stability of the ice shelf. Meanwhile, the iceberg, dubbed A68, which weighs more than a trillion tonnes, is floating on the Southern Ocean. Satellite images show that it is splintering and is surrounded by a group of smaller icebergs. It is drifting north towards the warmer waters of the South Atlantic Ocean, where it is likely to melt.
What happens now?
The continent of Antarctica is surrounded by several ice shelves like Larsen, which support the land glaciers, preventing them from falling into the sea. While collapsing ice shelves do not directly contribute to a rise in sea levels, they can unpin the land glaciers allowing them to flow more quickly into the sea and raise the sea level.
If all the ice covering the continent melted completely, it would raise the global sea level by 60 metres, submerging the world in water.
What can we do?
Unless we stop the planet from warming at the present pace, sea levels are projected to rise between two and seven feet by 2100. Considering the amount of carbon-dioxide already present in the atmosphere, it would be impossible to completely stop the sea from rising. However, by controlling emissions of greenhouse gases like carbon-dioxide, we can slow its pace and buy time to adapt. We can take small steps like planting trees, choosing public transport, reducing waste and being mindful of water and electricity consumption.
Effects on India
Coastal areas are most vulnerable to the rising sea levels and India, with its vast and densely populated coastline, has much to worry about.
According to a 2016 UN report, nearly 40 million people living in India’s coastal region will be at risk from rising sea levels by 2050. Coastal metros such as Mumbai, Chennai and Kolkata that have grown too rapidly, with no proper planning have experienced floods and could experience more in the future.
As saline sea water comes on shore, it will contaminate fresh groundwater, making it unsuitable for use. This could lead to severe water shortage and droughts. Many coastal areas are already facing these problems. Plant and animal life will also be affected by the eroding shoreline and changing coastal soil.
Some places in India, such as the Sunderbans and the Majuli riverine island are already witnessing the impact of rising sea levels. Recent studies and satellite images have shown that nearly four per cent of the Sunderbans, one of the world’s largest mangrove forests located in the coastal region of the Bay of Bengal, has been devoured by the sea, leading to a loss of biodiversity as well as livelihood for the locals.
Explore this interactive widget and find out more about icebergs and glaciers! Visit www.youngworldclub.com/frozen
