Shifts in weather fronts of the Southern Ocean: SPbU scientists
SPbU’s researchers have evaluated the results of the synoptic monitoring of the weather fronts in the Southern Ocean. The monitoring has been carried out for ten years during the annual expeditions of the Russian Antarctic Expedition (RAE) from Africa to Antarctica and back. A newly-developed method was successfully applied to study the meridional shifts of the surface thermal fronts of the Southern Ocean, an important indicator for the ocean climate in the Antarctica.
Located mostly in polar regions, the Arctic Ocean and Southern Ocean have specific spatial patterns and are covered by ice all year round. These oceans have a significant impact on climate in Southern and Northern Hemispheres, and their ice cover melt, primarily due to global warming, can have potential impact on the sea level rise.
“The insight into the physical processes in the upper layer of the oceans and seas is vital in understanding climate changes globally”, — said the author of the research, SPbU’s Associate Professor Viktor Ionov. The Southern Ocean is comparatively little studied, and no direct research has so far been carried out there, says Viktor Ionov.
A thorough and objective evaluation in the World Ocean is only possible if we carry out the synoptic monitoring of its surface thermal characteristics. For the first time, SPbU’s oceanologists, on board of the research vessel during the RAE’s seasonal expeditions, have combined direct measurements of the temperature of the sea surface layer (SSL) and satellite observations of the sea surface temperature (SST) in the Southern Ocean.
What makes the research different is georeferencing when making measurements of the temperature in the surface layer as the vessel moves forward, and operational satellite data on the temperature gradients with the high spatial resolution, says Viktor Ionov.
“The advent of GPS and GIS technologies, which are a core part of the software for operational on-board processing of the satellite images of the sea surface in the infra-red band, made it possible to carry out an operational monitoring of the fronts on-line”, — said the researcher. The monitoring of the latitudes of the main weather fronts on the surface of the Indian Ocean sector of the Southern Ocean in 2007-2016 has revealed a tendency that the weather fronts have been moving towards south, to the Antarctica, which makes the monitoring at the forefront of research.
The method of the synoptic monitoring of the surface thermal fronts of the Southern Ocean allows to obtain data on climate changes in the ocean circulations. All in all, SPbU’s scientists have significantly contributed into ocean studies and shed light on the under-studied region of the World Ocean.