12,000 Years of Climate Variability and sea Surface Temperatures in Antarctica
14.02.2011 - Atmosphere & Space, Water & Oceans, Land & Geology, Antarctic
A study conducted on an ocean sediment core extracted from the seabed along the coast of the Antarctic Peninsula is increasing scientists’ understanding of sea surface temperature and climate variability in the area.
Through the analysis of the biological material the sediments core contains, scientists are able to establish a continuous profile of sea surface temperatures as far back as the beginning of the Holocene, some 12,000 years ago. The Holcene has been a period characterized by a warm and relatively stable climate. From the information derived from the core, scientists have found that surface ocean temperatures at the margins of the peninsula cooled by 3-4°C over the past 12,000 years.
Published in the journal Nature, the study further suggests that the cooling is now offset by the current climate change, with sea temperatures rising at the same rate as land temperatures. It has also reinforced the hypothesis that fluctuations at the margins of the western Antarctic Peninsula during the Holocene have been tied to changes in the position of the westerly winds.
Current climate models are predicting El Niño and La Niña Southern Oscillation cycles will become more frequent and stronger. which has the potential to to weaken ice shelves along the Antarctic Peninsula and lead to their disintegration, which would contribute to sea level rise. However according to Dr Amelia Shevenell from the Department of Geogrpahy and Earth Sciences at University College London, lead author of the study, it is not possible to predict how much higher temperatures would have to be for this to happen.
