Arctic sea ice thinning faster than expected. Sea ice in Arctic coastal locations is shrinking up to twice as rapidly as previously anticipated. According to a recent modeling study that used data from the University College London (UCL) and other sources.
To determine sea ice thickness, you use an instrument that measures the height of the ice above the water. And the measurements are thrown off because of the weight of the snow on the ice floe. Scientists take steps to compensate for this inaccuracy using a map of snow depth in the Arctic. Which is decades out of date and does not account for climate change.
A new study was recently published in the journal “The Cryosphere” that utilized a new computer model to replace the map shown in the first study and used that model to estimate ice thickness variation across the Arctic in key coastal regions. Researchers discovered that the thinning of sea ice in these regions is occurring at a rate that is 70 to 100% faster than estimated in the first study.
We saw a change in the chemistry of the mixture. We saw a change in the composition of the mixture. “A diminished thickness of Arctic sea ice is an early indication of the Arctic’s health. Thick ice is a major insulator, with winter months when it is abundant acting to trap heat inside the water. 2) in the summer months when it is less abundant acting to block sunlight. Thinner ice will be less stable through the summer melt because it will break down quicker.”
To calculate the thickness of sea ice we used a snow map, 20 years ago. Which was the last update.
Sea ice formation is happening later and later in the year, and thus, the snow on top doesn’t have enough time to pile up. This is the first time our calculations have accounted for this reduced snow depth, and the results show that the ice shelf is shrinking quicker than we believed.
The study’s lead author, Professor Julienne Stroeve (UCL Earth Sciences), commented: “There are a number of uncertainties in measuring sea ice thickness, but we believe our new measurements are a significant advance over previously used calculations, with respect to how they more accurately interpret the data we have from satellites.
We hope this research can be used to better examine the performance of climate models that forecast the long-term consequences of climate change in the Arctic — a region that is warming three times faster than the rest of the world, and whose billions of square kilometers of ice are necessary to maintain global temperature equilibrium.
The researchers used radar from the European Space Agency’s CryoSat-2 satellite to determine the thickness of sea ice. The researchers studied how long it takes for the radar waves to bounce back off the ice, with which they determined the ice’s height above the water, using which they concluded the ice’s entire thickness.
The new study used a novel snow model
Previously developed by researchers at UCL and Colorado State University, called SnowModel-LG, which is capable of calculating snow depth and density using inputs such as air temperature, snowfall, and ice motion data to follow how much snow accumulates on sea ice as it moves around the Arctic Ocean.
The team performed all of the previous research, including a snow model simulation and satellite radar readings, and determined the overall rate of loss in sea ice thickness in the Arctic, as well as the year-to-year variability in sea ice thickness.
New models were developed, and the data was compared to previous models, with the newer model indicating a 70%, 98%, and 110% rise in the three coastal seas, Laptev, Kara, and Chukchi seas, respectively, in terms of decrease.
By correlating data from all seven coastal seas throughout the period from 1958 to 2009. They discovered that year-to-year variability in sea ice thickness had grown by 58% in all coastal seas.
The thickness of sea ice on the shoreline is normally anything from half a meter to two meters. As the amount of ice in this location diminishes, it is harder to keep the ice around during the summer. More and quicker thinning of sea ice in the coastal Arctic Seas has ramifications for human activity in the area. Particularly as it pertains to shipping in the Northern Sea Route during part of the year. As well as the exploitation of resources from the seabed, such as oil, gas, and minerals.
Arctic sea ice thinning faster than expected
Mallet explained. “It will help if more ships take the route around Siberia. Which would result in less fuel and carbon emissions used to transfer commodities across the globe. Notably between China and Europe.
“Although this increased risk increases the repercussions of a gasoline leak in the Arctic, which is disastrous. It is worth noting that an increase in risk entails an increase in financial load. While a thinning of coastal sea ice makes coastal towns more vulnerable to extreme weather and wave action. So, the same development may also be concerning for indigenous populations. As it exposes their villages to dangerous and volatile conditions from the ocean.”
In addition to being a co-author of this study. Mallett, Professor Stroeve, and his colleague Michel Tsamados from UCL Earth Sciences have contributed to investigating snow and ice in the Arctic aboard the German research vessel Polarstern. Which circumnavigated the central Arctic Ocean in 2019 and 2020.
The United Kingdom’s Natural Environment Research Council, the European Space Agency (ESA), And the United States National Aeronautics and Space Administration (NASA). Supports the researchers.