Recent changes in the Wanda Glacier, King George Island, Antarctica

Recent glaciological changes in Wanda Glacier, King George Island (KGI), South Shetland Islands (61°54’ S and 62°16’S, 57°35’W and 59°02’W) off the Antarctic Peninsula, were quantified by ice flow velocity, direction and fluctuation of glacier termini measurements. Topographic changes and DGPS surve...

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Bibliographic Details
Published in:Pesquisas em Geociências
Main Authors: ROSA, Kátia K., VIEIRA, Rosemary, FERNANDEZ, Guilherme, MENDES Jr., Claudio W., VELHO, Luiz Felipe, SIMÕES, Jefferson C.
Format: Article in Journal/Newspaper
Language:English
Published: Instituto de Geociências /Universidade Federal do Rio Grande do Sul 2015
Subjects:
Online Access:https://seer.ufrgs.br/index.php/PesquisasemGeociencias/article/view/78119
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Summary:Recent glaciological changes in Wanda Glacier, King George Island (KGI), South Shetland Islands (61°54’ S and 62°16’S, 57°35’W and 59°02’W) off the Antarctic Peninsula, were quantified by ice flow velocity, direction and fluctuation of glacier termini measurements. Topographic changes and DGPS surveys as well as transverse and longitudinal profiles were carried out to generate a Digital Surface Model. Results show that Wanda Glacier has a small drainage basin, a high retreat rate through fusion processes and reduced ice thickness if compared to other glaciers in KGI. Surface-area changes are assessed using historical satellite imagery from 1979 to 2011. Wanda glacier lost about 31 % of its original (1.5 km² of area in 1979). The current continuous and fast retreat phase is attributed to the recent regional warming. Maximum ice surface velocity, measured using a stake network, reached 2.2 cm d-1 during the period of 2007–2011. Transverse profiles show the influence of the topography on the ice flow. Due to its small size and thermal conditions, Wanda Glacier responds rapidly to climatic variations, revealing its relevance for environmental studies. Mudanças glaciológicas recentes na geleira Wanda, Ilha Rei George, Shetlands do Sul (latitudes 61°54’S a 62°16’S e longitudes 57°35’W a 59°02’W), fora da Península Antártica, foram quantificadas através de medidas da direção e velocidade do fluxo de gelo e das flutuações em sua posição frontal. Dados topográ- ficos e medidas de DGPS, bem como perfis transversais e longitudinais para a geleira foram obtidos para a geração de um Modelo Digital de Superfície. Os resultados demonstram que a geleira Wanda possui uma pequena bacia de drenagem, um alto grau de retração através de processos de fusão, e reduzida espessura se comparada com outras massas de gelo da Ilha Rei George. Mudanças em sua área foram obtidas pela utilização de imagens de satélite multitemporais do período de 1979 a 2011. A geleira Wanda perdeu aproximadamente 31 % de sua área original desde 1979 (1,5 ...