Why in the news?

• An iceberg named A68A which calved (broke) from Larsen C Ice shelf, Antarctica in 2017, is about to collide South Georgia Islands in the South Atlantic Ocean.

What is the difference between Iceberg and Ice shelf?

• Ice Shelf: An ice shelf is a floating extension of land ice.

• Ice Berg: Icebergs form when chunks of ice calve, or break off, from glaciers, ice shelves, or a larger iceberg. Icebergs travel with ocean currents, sometimes smashing up against the shore or getting caught in shallow waters.

About South Georgia Islands

• South Georgia & the South Sandwich Islands is a British Overseas Territory in the southern Atlantic Ocean.  
• It is home to several wildlife like penguins, albatrosses, seals, whales and petrels.

How are icebergs named?

• Naming of iceberg is done by the US National Ice Center (USNIC). Icebergs are named according to the Antarctic quadrant in which they are spotted.

How has the Iceberg reached South Georgia? 

• Ice berg A68A was detached from Larsen C ice shelf in July 2017. It was around 6000 sq km in area when it was carved out. 
• Over the years it was drifted north by water currents and it broke into several smaller icebergs but the parent iceberg i.e. A68A is still about the size of as much as twice the GOA state.
• Now it is just 50km away from South Georgia islands.

What is the issue with Ice berg A68A reaching South Georgia?

• Once the ice-berg collides with the South Georgia with a size it is now, it will take at least 10 years for the ice-berg to melt.
• South Georgia is home for a large penguin and Seal population, with ice-berg near them, it will take a longer period for the parent penguin population to fetch food. It is predicted that with Ice-berg near the island, the penguin population may be reduced 10% annually.
• It is also believed that the fresh water from the iceberg will affect the fragile ecosystem of the island and in turn the food chain will be destabilized. With this, it will affect the local fishing population.
• There are some positive effects like Iceberg will bring a lot of dust which fertilises ocean plankton, which draws up carbon dioxide from the atmosphere but it is a long term process.
• It is an inevitable event which humans can’t stop, but it will be an opportunity for the human race to study this event and know what climate change is doing to the earth and take measures appropriately.

References:

1. http://www.antarcticglaciers.org/glacier-processes/glacier-types/ice-shelves-sea-ice-icebergs/
2. https://nsidc.org/cryosphere/quickfacts/icebergs.html
3. https://www.gov.gs/
4. https://indianexpress.com/article/explained/explained-where-is-the-giant-antarctic-iceberg-a68a-heading-and-why-is-it-a-cause-for-concern-7121945/
5. https://www.youtube.com/watch?v=L9SMn-6KSwg&feature=emb_rel_end&ab_channel=ThePrint