High Temperatures Reduces Dakshin Gangotri

The Dakshin Gangotri Glacier is a small tongue of the polar continental ice sheet impinging on the Schirmacher Oasis of central Queen Maud Land, Antarctica. It was discovered by the Second Indian Expedition to Antarctica in 1983, and named for India’s first Antarctic research station.

Since then its snout, and the area around it, has been regularly monitored and it has become a valuable site for tracking the impact of global warming through changes in the movement of the Antarctic ice sheet.

The site is protected under the Antarctic Treaty System as Antarctic Specially Protected Area (ASPA) No.163.

According to latest paper in the first volume of Antarctic research by India published in the Proceedings of the Indian National Science Academy, the Dakshin Gangotri (DG) glacier is fast melting away because of rise in global temperatures.

Highlights of the Report:

Dakshin Gangotri glacier is located in the western part of Schirmacher Oasis. This Oasis is located at a distance of more than 2000km north of geographic South pole, at Princess Astrid coast of East Antarctica.

In this Oasis, the second research base of India “Maitri” is located. This station was commissioned in the year 1989.

The Geological Survey of India has been monitoring Dakshin Gangotri glacier snout since the beginning of Indian Antarctic Expedition in 1982.

Continuous data over the last two decades shows a phase of major recession in DG glacier snout every five years, and minor recession at every two to three year interval between 1996 and 2010.

During 2014-15, the DG glacier snout receded by 1.31m as compared to the previous year. Similarly, the western wall receded by 2.37m from the previous year.

The analysis found that the shrinking of the DG snout between 1996 and 2011 has cleared 4800 square metres (m2) area. This figure increases by about 10 times after including the vacated area by Western wall.

The Russian Novolazarevskaya research station has estimated that since 1996, average surface air temperature varies between -9.2 degree Celsius and -11.1 degrees Celsius.

The present calculation indicates the disappearance of ice from the snout of Dakshin Gangotri glacier, which is a part of East Antarctic Ice Sheet is related to the meteorological parameters such as increase in surface air temperature, ground temperature and wind speed.

The observation shows that the decline in ice mass is more pronounced at the western wall that lies at a higher elevation and therefore receives more solar radiation.

During the period 2001 to 2016, the recession of ice in the western wall saw two peaks – that of 10.96m in 2002-2003 and 10.45m in 2012-2013. At 1.31 metres, the decline in ice at the DG snout glacier was the highest in 2014-15 followed by 1.21m (2002-03), 1.10m (2007-08 and 2008-09) and 1.01m (1997-98).

Antarctica and Greenland hold 90% of the total ice of the earth. The Antarctic environment also controls many ocean circulations which is essential to marine life, and is directly related to our existence.