Severe winters experienced in Europe and in Asia may have been initiated by the melt or decline in the Arctic sea ice, Japanese researchers suggested in a new study published in the Nature Geoscience journal.
The researchers wrote that it may have been initiated through the “excitation of circulation anomalies similar to the Arctic Oscillation.”
Emeritus associate Colin Summerhayes of the Scott Polar Research Institute
said in a statement that the “counterintuitive effect of the global warming that led to the sea ice decline in the first place makes some people think that global warming has stopped,” though “it has not.”
Led by researchers from the Atmosphere and Ocean Research Institute of the University of Tokyo, the study used 100-member collective simulations together with an atmospheric general circulation model that was driven by observed sea-ice concentration anomalies. This was used in order to illustrate that the possibility of severe winters in cental Eurasia has more than doubled because of the reduction of sea-ice in Barents-Kara Sea.
The atmospheric response to the decline in sea-ice is nearly free of the Arctic Oscillation, researchers said.
“Both reanalysis data and our simulations suggest that sea-ice decline leads to more frequent Eurasian blocking situations, which in turn favour cold-air advection to Eurasia and hence severe winters,” read the letter of the study.
The researchers concluded that cold winters driven by sea-ice are not likely to lead in a warming climate in the future, as based on further examination of simulations out of 22 climate models. Nevertheless, they admitted that it still remains uncertain, partly because of an inadequate ensemble size.
The findings of the Japanese researchers were said to have matched well with another current study focusing on the area of Barents-Kara Sea, according to Rutgers University researcher Jennifer Francis in a report by Climate Central. Francis was the first one to have proposed a possible link between sea-ice changes and severe weather at lower latitudes.
Meanwhile, according to Bloomberg Businessweek, the United Nation’s Intergovernmental Panel on Climate Change (IPCC) has gathered around 2,000 envoys, who will meet in Copenhagen this week to talk about their “most extensive assessment yet of climate science” meant to provide guidance to 190 nations set to meet in Peru in December. The nations will discuss new methods to decrease emissions of greenhouse gases after year 2020.
Supplementary information on the paper, Robust Arctic sea-ice influence on the frequent Eurasian cold winters in past decades, can be accessed here [pdf].
