The warming of the Tasman Sea is warming the Antarctic Peninsula’s climate due to changes in wind patterns, a new study by Japanese and Australian scientists shows
RESEARCH ORGANIZATION OF INFORMATION AND SYSTEMS
IMAGE: Warming in the Tasman Sea results in warm winters and melting of the ice in Antarctica. show more CREDIT: KAZUTOSHI SATO (KITAMI INSTITUTE OF TECHNOLOGY)
The melting of the Earth’s ice sheet increased in the 20th century, and glaciers and sea ice in the Arctic and Antarctic regions were melting at alarming rates. In fact, the Antarctic Peninsula (AP), the only landmass in Antarctica that extends beyond the Arctic Circle, has been found to be one of the fastest warming regions on earth in the second half of the 20th century. This rapid climate change has raised serious sea level rise concerns around the world.
Several factors have been linked to the melting of the ice sheet: The main one is greenhouse gas emissions from human activities, which cause warming of the atmosphere and oceans and the resulting melting of the ice. Apart from that, atmospheric fluctuations, ocean currents and wind patterns also play an important role. A collaborative group of scientists from Japan and Australia – led by Assistant Professor Kazutoshi Sato from the Kitami Institute of Technology and Associate Professor Jun Inoue from the National Institute for Polar Research in Japan – has now focused on understanding how variations in these climatic factors affect climate affect Antarctica warming. They documented their findings in a brand new article published in Nature Communications.
Previous studies have examined the relationship between wind dynamics over the Southern Ocean (also called SE; north of Antarctica) and climate variability in tropical oceans. In tropical regions, warming has been found to create atmospheric waves called “Rossby waves” across the SE from the tropics to Antarctica, warming West Antarctica. Interestingly, Rossby waves are nature’s attempt to balance the heat in the atmosphere by transferring heat from the tropics to the poles and cold air to the tropics.
On the path to understanding AP warming, Dr. Sato points out, “The effects of climate variability in the mid-latitudes of the southern hemisphere on this warming of Antarctica have yet to be quantified.” His team has closed this gap by studying climatic changes in the Tasman Sea between Australia and New Zealand and the SE and has drawn correlations with temperature fluctuations in the AP.
Dr. Sato and his team analyzed the temperature data from six stations in AP as well as the wind and cyclone patterns over the Tasman Sea and SE from 1979 to 2019. They found that even without unusual warming in the tropics, only warming in the Tasman changes the sea the wind patterns over the SE, forcing the Rossby waves to move even deeper into the Amundsen Sea Depression, a low pressure area west of the AP. This greater pressure gradient causes stronger colder winds towards the poles. The meandering wind current moves towards AP, which leads to the warming of this region. In addition, it was found that this effect is pronounced in the winter months when the cyclones are more active. “We have shown that warm winter episodes in the Tasman Sea affect warm temperature anomalies in key regions of West Antarctica, including the AP, through a poleward shift in the South Pacific cyclone tracks,” concludes Dr. Sato together.
The increasing warming of the AP – more likely the whole of Antarctica as a whole – is a major concern of climatologists around the world. Dr. Commenting on the severe impact of this rapid rise in temperature and sea level, and the significance of the results of her study, Inoue said, “Antarctic warming is accelerating the melting of the Antarctic ice sheet and is contributing to sea level rise around the world. Therefore, knowing the mechanisms behind the melting of the Antarctic ice sheet would help scientists, policymakers, and administrations develop measures for people most affected by sea level rise. “
Dr. Sato and his team conclude by stating that the results of their study may also support future prediction of the melting of the Antarctic ice sheet and the resulting global rise in sea level.
Via the Kitami Institute of Technology, Japan
The Kitami Institute of Technology is a national university in Kitami, Hokkaido, Japan. It was founded as the Kitami Junior College of Technology on April 1, 1960 and chartered as a university on April 1, 1966. In 2004 it became part of the National University Corporation.
About Dr. Kazutoshi Sato from the Katami Institute of Technology, Japan
Dr. Kazutoshi Sato is an Assistant Professor at the Kitami Institute of Technology in Japan. He worked as a project researcher at the National Institute of Polar Research in Japan. His research group is interested in understanding climate variability and its effects on sea level rise.
About the National Institute for Polar Research (NIPR)
The NIPR conducts extensive research on observation stations in the Arctic and Antarctic. As a member of the Information and Systems Research Organization (ROIS), the NIPR provides researchers across Japan with infrastructure support for observations in the Arctic and Antarctic, plans and implements Japan’s Antarctic observation projects, and conducts Arctic research in various scientific fields such as the atmosphere, ice sheets, the ecosystem, the upper atmosphere, the aurora, and the earth’s magnetic field. In addition to the research projects, the NIPR also organizes the Japanese Antarctic Research Expedition and manages samples and data obtained during such expeditions and projects. As the core institution for research in the polar regions, the NIPR also offers doctoral students a global perspective on originality through its doctoral program. Further information on the NIPR can be found at: https: // http: //www.nipr.ac.jp/english/
About the Research Organization for Information and Systems (ROIS)
The Research Organization for Information and Systems (ROIS) is a parent organization of four national institutes (National Institute for Polar Research, National Institute for Computer Science, Institute for Statistical Mathematics and National Institute for Genetics) and the Joint Support Center for Data Science Research. It is ROIS’s mission to promote integrated, cutting-edge research that goes beyond the barriers of these institutions and facilitates their research activities as members of inter-university research institutes.