Eu-R-Cool: EuRasian Cooling in CMIP5 Models

Investigating the representation of Euriasan cooling in the CMIP5 models. 

Objectives

  1. Submitted publication on Eurasian cooling CMIP5 models
  2. Submitted publication on representation of dynamical processes in the Arctic in CMIP5 models

Project Summary

There has been great interest and debate regarding the unusually low sea ice extent (SIE) over the Arctic in recent weeks, and while the summer minimum wasn’t record breaking, it is the sea-ice’s failure to recover since then that has sparked concern. The average SIE for 1981-2010 for this late in November is around 11.5M km2, but currently it is approximately 9.25M km2, a deficit of around 20%. While such a low SIE is unprecedented for this late in the year, it is the temperature response that is even more striking (Figure 1). In parts of the Arctic, surface air temperatures (SAT) have reached up to 20°C above their long term average, while at the same time, Northern Eurasia has experienced extreme cooling. Many studies have investigated the links between sea ice loss and the so-called Eurasian Cooling that occurs during wintertime [Cohen et al., 2012; Outten and Esau, 2012; Petoukov and Semenov, 2010; Mori et al., 2014]. They have found that changes in the large-scale flow and the reduction of the meridional temperature gradient both contributed to the reduced temperatures seen over continental Eurasia. Since our previous studies into Eurasian Cooling [Outten and Esau, 2012; Outten et al., 2013] and work on the temperature hiatus [Outten et al., 2015; Thorne et al., 2015], my colleagues and I have continued to investigate this phenomenon, focussing on the question of how well do the climate models reproduce this observed cooling over Eurasia and the associated teleconnection with the Arctic sea ice. Given the heightened interest in recent weeks, and what promises to be a very interesting winter in terms of Arctic temperatures and sea ice, we feel this is an opportune moment to consolidate and publish our resusults.

 
Project Details
Acronym: 
Eu-R-Cool
NERSC Principal Investigator: 
Stephen Outten
Coordinating Institute: 
Nansen Environmental and Remote Sensing Center
Project Status: 
Completed