When investigating the Arctic, researchers came to a frightening result: the thickness of the sea ice there is decreasing significantly faster than previous models have shown. This has serious consequences for the climate.
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British climatologists have sounded the alarm in a new study and warned of dramatic ice melt in the Arctic. The sea ice thickness in the coastal regions of the Arctic is decreasing 70 to one hundred percent faster than generally assumed, according to the study published on Friday in the specialist magazine “The Cryosphere”. The sea ice in the Arctic keeps the earth cool – its disappearance would therefore exacerbate climate change from the point of view of scientists.
“From our point of view, our calculations are a huge step forward when it comes to the more precise interpretation of data from satellite data,” said co-study author and professor at University College London (UCL), Julienne Stroeve. According to the scientist, the affected Arctic region is warming three times as much as the earth as a whole.
Determination using satellite data
To determine the thickness of the sea ice, scientists measure the part of the ice that protrudes from the ocean. However, the values are distorted by the snow that lies on the clods and pushes them down. For their study, the UCL researchers said they used more up-to-date satellite data from the European Space Agency (ESA) than were used in previous studies and combined them with calculations from a new climate model that they had developed together with US scientists from the University of Colorado.
“Previous measurements of sea ice thickness were based on a snow map that was last updated 20 years ago,” said PhD student and lead author Robbie Mallett. “Because the sea ice started to form later in the year, the snow on top of it has less time to pile up,” he said. The study presented by him and his colleagues takes this phenomenon into account for the first time. The result is that “the sea ice is thinning out faster than we thought”.
Sea ice thickness as an important indicator
The sea ice thickness is an important “indicator of the health of the Arctic,” stressed Mallett. Thick layers of sea ice served as a type of thermal insulation that prevented the Arctic Ocean from warming the earth’s atmosphere in winter. In summer, the floes protected the ocean from solar radiation. “Thinner ice also has a poorer chance of survival during the Arctic summer melt,” said Mallett.
The melting of ice in the Arctic is also fueling geopolitical tensions in the region, as neighboring states see opportunities for the development of previously unused resources and the potential for new sea routes in the disappearance of the floes. At a meeting of foreign ministers at the end of May, eight countries bordering the polar region, including the USA and Russia, agreed on peaceful cooperation to combat global warming.