A study reported in the Nature journal by a team of polar scientists from France, Australia and the United Kingdom has provided new insights into climate change in the Antarctic Peninsula region and the possible reasons for the collapse of its ice shelves.
Using an ice core obtained from James Ross Island located in the Antarctic Peninsula, the study recreated a climate history of the past 15,000 years when the Earth came out from the final ice age and entered into the existing warm period.
Lead author, Robert Mulvaney stated that researchers are trying to find out the role of natural climate variation and human activity since the industrial revolution in the recently observed warming on Earth. Ice cores are a better technique to get the climate history experienced by Earth during ice ages and warm periods.
The researchers are aware that the Antarctic Peninsula is facing an unusual problem. To find out this issue, they used James Ross Island ice core comprising layers of snow that fell each year over the past 50,000 years. They recreated a temperature history over this period using an advanced chemical analysis at the NERC Isotope Geosciences Laboratory and BAS. From the ice core temperature record, the researchers observed a 6°C increase in temperature in the Antarctic Peninsula as it came out from the last ice age. Before 11,000 years, the temperature had increased to around 1.3 °C warmer when compared to current average.
Moreover, the Antarctic Peninsula ice sheet started shrinking at this period and some neighboring ice shelves retreated. Then, the local climate reached its minimum nearly 600 years ago by getting cooled in two stages. This cooling also resulted in the expansion of northern Antarctic Peninsula ice shelves. Nearly at this period, the local temperature began to warm again, subsequently increasing more rapidly in the past 50-100 years that corresponds with today’s break-up of ice shelves and glacier retreat.
Co-Author, Nerilie Abram the continuation of rapid warming may affect ice shelves further south alongside the Peninsula, which have been stable for the past several thousands of years. The study findings provide insights into the role of Antarctica’s ice sheets in impacting future sea-level rise and climate change.
Source: http://www.bgs.ac.uk