Disquieting Findings from Analysis of Sediment Core Taken from Northern Antarctic Peninsula
10.11.2009 - Water & Oceans, Ice & Snow, Other, Antarctic
According to a recent study conducted by researchers from the NationalOceanography Centre, Southampton (NOCS) and the University ofSouthhampton's School of Ocean and Earth Science (SEOS), not once in the past 14,000 years has there been a period of warmingand ice loss similar to the one we are currently experiencing, which highlights the seriousness of current climate change.
The findings come from the analysis of a nearly-complete 108.3-metre sediment core retrieved at Maxwell Bay - the thickest sediment core yet drilled in the Antarctic Peninsula region - on a mission aboard the RV/IB Nathaniel B. Palmer in 2005. In conducting in-depth sedimentological and geochemical analyses on the core, the scientists were able to determine past ice conditions in the region gong back more than 14,000 years.
Their findings point towards a period of glacial retreat from 10,100 to 8,200 thousand years ago, followed by a period of reduced sea-ice cover and warmer waters between 8,200 and 5,900 thousand years ago. An important discovery is that the Holocene warming interval (Holocene climatic optimum), which occurred between 9,000 and 5,000 years ago, did not happen uniformly at a single time and was locally influenced by oceanographic controls and physical geography.
After this warmer interval, the climate started cooling over the next 3,000 years, allowing more ice cover in the bay to develop. However scientists found no evidence that the ice at Maxwell Bay advanced during the Little Ice Age, which lasted from the sixteenth until mid-nineteenth century.
Over the past five decades the Antarctic Peninsula has seen average temperatures increase by 3°C, an increase in rainfall and widespread glacier retreat.
