Satellite records spanning three decades confirm the dramatic transformation of Arctic ice. Ice coverage has steadily decreased, becoming thinner and more mobile. Until recently, detailed monitoring of pressure ridges was unavailable due to technological constraints. However, recent analysis offers the first comprehensive look at these critical formations.
Pressure ridges arise when ocean currents or wind forces collide ice floes, creating thick formations with above-water "sails" and underwater "keels" extending up to 30 meters deep. These features influence the ecosystem and Arctic processes, providing habitats for polar bears, fostering nutrient mixing in ocean waters, and impacting ice dynamics.
AWI researchers, using data from 30 years of research flights totaling over 76,000 kilometers, have documented a 12.2% reduction in pressure ridge frequency and a 5% reduction in height per decade in key Arctic regions. The Lincoln Sea, where old ice once dominated, shows a 14.9% decrease in frequency and a 10.4% decrease in height per decade.
Dr. Thomas Krumpen, the study's lead author, explained, "More and more of the Arctic consists of ice that melts in the summer and is no more than a year old. This young, thin ice can more readily be deformed and rapidly forms new pressure ridges. However, the loss of older, multiyear ice, which had accumulated many pressure ridges, has led to an overall decline in their frequency."
The findings indicate the most significant changes occur in areas where ice age has dramatically reduced, such as the Beaufort Sea and the Central Arctic. These regions, now partly ice-free in summer, were once dominated by five-year-old ice, highlighting the extensive impact of climate change on Arctic ice.
Using precise aerial laser measurements, AWI researchers were able to map pressure ridge terrain with unprecedented detail. Flights, conducted at altitudes under 100 meters, began in the 1990s and continue to provide valuable insights into Arctic ice dynamics.
Research Report:Smoother ice with fewer pressure ridges in a more dynamic Arctic
Related Links
Alfred Wegener Institute
Beyond the Ice Age
Subscribe Free To Our Daily Newsletters |
Subscribe Free To Our Daily Newsletters |