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Arctic sea ice succumbs to Atlantification


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CryoSat key to measuring sea-ice thickness

With alarm bells ringing about the rapid demise of sea ice in the Arctic Ocean, satellite data have revealed how the intrusion of warmer Atlantic waters is reducing ice regrowth in the winter. In addition, with seasonal ice more unpredictable than ever, ESA’s SMOS and CryoSat satellites are being used to improve sea-ice forecasts, which are critical for shipping, fisheries and indigenous communities, for example.

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      The sea level change team undertook the analysis of this region at the request of several Pacific Island nations, including Tuvalu and Kiribati, and in close coordination with the U.S. Department of State.
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      Team members, led by researchers at the University of Hawaii and in collaboration with scientists at the University of Colorado and Virginia Tech, started with flood maps of Kiribati, Tuvalu, Fiji, Nauru, and Niue. They plan to build high-resolution maps for other Pacific Island nations in the near future. The maps can assist Pacific Island nations in deciding where to focus mitigation efforts.
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      Researchers would like to combine satellite data on ocean levels with ground-based measurements of sea levels at specific points, as well as with better land elevation information. “But there’s a real lack of on-the-ground data in these countries,” said Hamlington. The combination of space-based and ground-based measurements can yield more precise sea level rise projections and improved understanding of the impacts to countries in the Pacific.  
      “The future of the young people of Tuvalu is already at stake,” said Malie. “Climate change is more than an environmental crisis. It is about justice, survival for nations like Tuvalu, and global responsibility.”
      To explore the high-tide flooding maps for Pacific Island nations, go to:
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