July 21, 2015

Hindle Glacier, Accelerating Retreat, South Georgia

Posted by Mauri Pelto

hindle 89-15

Landsat Image of Ross Hindle Glacier 1989 left and 2015 right.  Something changed.

South Georgia sits amidst the furious if not screaming fifties latitude belt, the circum Antarctic westerlies. This region is famous for the endless march of storms parading around Antarctica. The island is south of the Antarctic Convergence, preventing any truly warm season from persisting. The cool maritime climate leads to numerous glaciers covering a majority of the island and quite low equilibrium line altitudes.  Ross-Hindle Glacier enters Royal Bay on the east coast of South Georgia Island has now separated into the Ross and Hindle Glaciers. Hindle Glacier could do well  in a new international Olympic event, “Fastest Retreating Glacier” The tidewater glaciers of South Georgia in general maintained fairly advanced positions unitl 1980. Gordon et al., (2008) observed that larger tidewater and sea-calving valley and outlet glaciers generally remained in relatively advanced positions until the 1980s. For Ross-Hindle the retreat was minimal from 1960 to 1989. The change in glacier termini position have been documented by Alison Cook at British Antarctic Survey in a BAS retreat map.  By 2008 the glaciers had separated. Here we examine Landsat imagery from 1989 to 2015 to identify recent change.

hindle area2

Region of Hindle Glacier on South Georgia.

BAS map of glacier front change.

In 1989 the glacier extends to the green arrows with a joint terminus that is three kilometers long. This is quite close to the 1960 terminus location. By 2003 the glacier has retreated  800 m with the south side nearly reaching a Point where the Hindle Glacier turns south  By 2008 the glaciers have separated, with a further retreat  of 1.5 km along the southern margin of Ross Glacier and western margin of Hindle Glacier. Retreat is much less on the northern side of Ross Glacier and the eastern side of Hindle Glacier.  By 2015 a new fjord has opened, as Hindle Glacier retreats south 1.7 km on the east margin and 2.1 km on the west side in just seven years.Ross Glacier continues to retreat west with a retreat of 600-700 m since 2008.

In Google Earth by 2010 there is  added crevassing near the ice front of Hindle Glacier that indicates an acceleration of the glacier. This suggests the Ross Glacier was impeding its flow previously and that Hindle is in a rapid retreat mode.The rapid recent retreat parallels that of Neumayer Glacier and Twitcher Glacier during the 1989-2014 period. The BAS research effort on glacier front retreat has been documented by Alison Cook . Her comparison of glacier fronts from old aerial photographs and comparing them with satellite images — she identified that 212 of the Peninsula’s 244 marine glaciers have retreated over the past 50 years and that rates of retreat are increasing.

hindle 1989

1989 Landsat Image

ross hindle 2003

2003 Landsat Image

2008 Landsat Image

ross Hindle 2015

2015 Landsat Image