Articles | Volume 17, issue 9
https://doi.org/10.5194/tc-17-4133-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-17-4133-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
22 Sep 2023
Research article |
| 22 Sep 2023
| 22 Sep 2023
Forced and internal components of observed Arctic sea-ice changes
Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
David B. Bonan
California Institute of Technology, Pasadena, California, USA
Marius Årthun
Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Lea Svendsen
Geophysical Institute, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway
Robert C. J. Wills
Department of Atmospheric Sciences, University of Washington, Seattle, Washington, USA
Institute for Atmospheric and Climate Science, ETH Zurich, Zurich, Switzerland
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Antarctic sea ice has exhibited variability over satellite records, including a period of gradual expansion and a period of sudden decline. We use a novel statistical method to identify sources of variability in observed Antarctic sea ice changes. We find that the gradual increase in sea ice is likely related to large-scale temperature trends, and periods of abrupt sea ice decline are related to specific flavors of equatorial tropical variability known as the El Niño–Southern Oscillation.
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The Barents Sea is the region of most intense winter sea ice loss, and future projections show a continued decline towards ice-free conditions by the end of this century but with large fluctuations. Here we use climate model simulations to look at the occurrence and drivers of rapid ice change events in the Barents Sea that are much stronger than the average ice loss. A better understanding of these events will contribute to improved sea ice predictions in the Barents Sea.
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Discipline: Sea ice | Subject: Climate Interactions
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Short summary
The Arctic sea-ice cover is retreating due to climate change, but this retreat is influenced by natural (internal) variability in the climate system. We use a new statistical method to investigate how much internal variability has affected trends in the summer and winter Arctic sea-ice cover using observations since 1979. Our results suggest that the impact of internal variability on sea-ice retreat might be lower than what climate models have estimated.
The Arctic sea-ice cover is retreating due to climate change, but this retreat is influenced by...
