From UPSC perspective, the following things are important :
Prelims level : Ice Shelves, Amery Ice Shelf
Mains level : Impact of climate changes
There would be a 24% increase in the expansion of the Amery Ice Shelf (AIS) boundaries in Antarctica by 2021 and another 24 per cent by 2026 from its 2016 positions, the National Centre for Polar and Ocean Research (NCPOR) in Goa has predicted.
Practice question for mains:
Q. Discuss the interrelation between Cryosphere and Climate change in context to the melting ice shelves in the Antarctic region.
Amery Ice Shelf (AIS)
- The Amery Ice Shelf is a broad ice shelf in Antarctica at the head of Prydz Bay between the Lars Christensen Coast and Ingrid Christensen Coast.
- It is part of Mac. Robertson Land.
- The name “Cape Amery” was applied to a coastal angle mapped on February 11, 1931.
- The AIS is one of the largest glacier drainage basins in the world, located on the east coast of Antarctica, at about 70ºS Latitude, 70ºE Longitude.
- The AIS dynamics and mass balance help in understanding the changes in the global climate scenario.
Significance of the study
- NCPOR observations revealed a critical cooling of the sea surface temperature, resulting in an advancement of the ice shelf by 88 per cent in the past 15 years.
- These changes would contribute in a major way to climate variability.
- The study clearly demonstrated the future dynamism of ocean heat fluctuation and Antarctic Amery ice shelf mass shifting-extent.
Back2Basics: Ice Shelves
- The floating sheets of ice called ‘ice shelves’ play a multi-faceted role in maintaining the stability of a glacier. Ice shelves connect a glacier to the landmass.
- The ice sheet mass balance, sea stratification, and bottom water formation are important parameters for the balancing of a glacier. Latent and sensible heat processes do play important roles here.
- The insulation of ice shelves from atmospheric forcing is dependent on a temperature gradient that the ocean cavity beneath the ice shelves provides.
- It is the pressure exerted by the ice shelves upon the ocean cavity that determines this temperature gradient.