FastFind »   Lastname: doi:10.1029/ Year: Advanced Search  

AGU: Geophysical Research Letters

 

Keywords

  • Arctic
  • CMIP5
  • climate projections
  • sea ice

Index Terms

  • 0750 - Sea ice
  • 1616 - Climate variability
  • 1621 - Cryospheric change
  • 1626 - Global climate models
  • 9315 - Arctic region

Paper in Press

GEOPHYSICAL RESEARCH LETTERS, doi:10.1029/2012GL052868

A sea ice free summer Arctic within 30 years-an update from CMIP5 models

Key Points
  • A nearly sea ice free summer Arctic is projected by the 2030s
  • There is little consensus on causes for spread in projections among CMIP5 models
  • Arctic sea ice loss is a major indicator of local and global change

Authors:

Muyin Wang

James E. E. Overland

Three years ago we proposed that the summer Arctic would be nearly sea ice free by the 2030s; "nearly" is interpreted as sea ice extent less than 1.0 million km2. We consider this estimate to be still valid based on projections of updated climate models (CMIP5) and observational data. Similar to previous models (CMIP3), CMIP5 still shows a wide spread in hindcast and projected sea ice loss among different models. Further, there is no consensus in the scientific literature for the cause of such a spread in results for CMIP3 and CMIP5. While CMIP5 model mean sea ice extents are closer to observations than CMIP3, the rates of sea ice reduction in most model runs are slow relative to recent observations. All CMIP5 models do show loss of sea ice due to increased anthropogenic forcing relative to pre-industrial control runs. Applying the same technique of model selection and extrapolation approach to CMIP5 as we used in our previous paper, the interval range for a nearly sea ice free Arctic is 14 to 36 years, with a median value of 28 years. Relative to a 2007 baseline, this suggests a nearly sea ice free Arctic in the 2030s.

Received 28 June 2012; accepted 9 August 2012.

Citation: Wang, M. and J. E. E. Overland (2012), A sea ice free summer Arctic within 30 years-an update from CMIP5 models, Geophys. Res. Lett., doi:10.1029/2012GL052868, in press.