IMPACT OF ATMOSPHERIC CO2 CONCENTRATION ON ANTARCTIC SEA ICE.

Five numerical experiments were conducted using a coupled model of intermediate complexity, lasting for 1500 modeled years, using different CO2 concentrations (500, 600, 700 and 800 ppm). It was observed that increased atmospheric CO2 concentration leads to a warming in the Southern Hemisphere polar...

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Bibliographic Details
Main Authors: Justino, Flávio, Hastenreiter, Felipe, Grimm, Alice, Schaefer, Carlos
Format: Article in Journal/Newspaper
Language:Portuguese
Published: Associação Brasileira de Ciência Ecológica e Conservação 2017
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Online Access:https://revistas.ufrj.br/index.php/oa/article/view/8061
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Summary:Five numerical experiments were conducted using a coupled model of intermediate complexity, lasting for 1500 modeled years, using different CO2 concentrations (500, 600, 700 and 800 ppm). It was observed that increased atmospheric CO2 concentration leads to a warming in the Southern Hemisphere polar region with serious implications on the sea ice cover. Numerical results revealed ice thickness reduction up to 1m in Weddell and Amuddsen Seas. In east Antarctic, from the Ross Sea to the Indian part of Antarctic Ocean, the absence of sea ice is the most prominent feature in the sensitivity experiments. The initial investigation indicates that the enhanced oceanic heat transport plays the main role in the modifications of the Southern Hemisphere sea ice under different CO2 concentration as determined by the CO2 simulations. Com base em 5 experimentos de sensibilidade numérica conduzidos com um modelo acoplado de intermediária complexidade, extendendo-se por 1500 anos do modelo, e com diferentes níveis de CO2 (500, 600, 700 e 800 ppm), demonstra-se que o aumento na concentração de CO2 leva a um aquecimento da região polar austral com sérias implicações na cobertura de gelo marinho. Os resultados numéricos mostram claramente a redução na espessura do gelo em até 1m, em particular no mar de Weddell e no mar de Amundsen. Na parte leste da Antártica, desde o mar de Ross até a zona Antártica do oceano Índico, a ausência do gelo foi a característica principal dos experimentos de sensibilidade climática. Numa análise inicial, nota-se que estas anomalias na criosfera deve-se a um substâncial aumento na quantidade de calor oceânico transportado para a região Antártica.