Since the level of Arctic sea ice set a new record low in 2007, significantly above-normal winter snow cover has been seen in large parts of the northern United States, northwestern and central Europe, and northern and central China. During the winters of 2009-2010 and 2010-2011, the Northern Hemisphere measured its second and third largest snow cover levels on record.
“Our study demonstrates that the decrease in Arctic sea ice area is linked to changes in the winter Northern Hemisphere atmospheric circulation,” said Judith Curry, chair of the School of Earth and Atmospheric Sciences at Georgia Tech. “The circulation changes result in more frequent episodes of atmospheric blocking patterns, which lead to increased cold surges and snow over large parts of the northern continents.”
The study was published on Feb. 27, 2012 in the online early edition of the journal Proceedings of the National Academy of Sciences. The research was supported by NASA and the National Science Foundation.
In this study, scientists from Georgia Tech, the Chinese Academy of Sciences and Columbia University expanded on previous research by combining observational data and model simulations to explore the link between unusually large snowfall amounts in the Northern Hemisphere in recent winters and diminishing Arctic sea ice.
The researchers analyzed observational data collected between 1979 and 2010 and found that a decrease in autumn Arctic sea ice of 1 million square kilometers -- the size of the surface area of Egypt -- corresponded to significantly above-normal winter snow cover in large parts of the northern United States, northwestern and central Europe, and northern and central China.
The analysis revealed two major factors that could be contributing to the unusually large snowfall in recent winters -- changes in atmospheric circulation and changes in atmospheric water vapor content -- which are both linked to diminishing Arctic sea ice. Strong warming in the Arctic through the late summer and autumn appears to be enhancing the melting of sea ice.
“We think the recent snowy winters could be caused by the retreating Arctic ice altering atmospheric circulation patterns by weakening westerly winds, increasing the amplitude of the jet stream and increasing the amount of moisture in the atmosphere,” explained Jiping Liu, a senior research scientist in the School of Earth and Atmospheric Sciences at Georgia Tech. “These pattern changes enhance blocking patterns that favor more frequent movement of cold air masses to middle and lower latitudes, leading to increased heavy snowfall in Europe and the Northeast and Midwest regions of the United States.”
Diminishing Arctic sea ice can cause changes in atmospheric circulation that lead to a circulation pattern that is different than the “negative phase” of the Arctic Oscillation.
In addition to analyzing observational data, the researchers also assessed the impact of the diminishing Arctic sea ice on atmospheric circulation by comparing the results of model simulations run with different sea ice distribution. They ran one experiment that assumed seasonally varying Arctic sea ice and utilized sea ice concentration data collected between 1979 and 2010. Another simulation incorporated prescribed sea ice loss in autumn and winter based on satellite-derived Arctic sea ice concentrations.
The simulations showed that diminishing Arctic sea ice induced a significant surface warming in the Arctic Ocean and Greenland/northeastern Canada, and cooling over northern North America, Europe, Siberia and eastern Asia. The models also showed above-normal winter snowfall in large parts of the northern United States, central Europe, and northern and central China.
The consistent relationships seen in the model simulations and observational data illustrate that the rapid loss of sea ice in summer and delayed recovery of sea ice in autumn modulates snow cover, winter temperature and the frequency of cold air outbreaks in northern mid-latitudes.
Huijun Wang and Mirong Song of the Chinese Academy of Sciences Institute of Atmospheric Physics and Radley Horton from the Columbia University Center for Climate Systems Research also contributed to this work.
This project was supported by the NASA Energy and Water Cycle Study and the National Science Foundation (NSF) (Award No. ANT-0838920). The content is solely the responsibility of the principal investigators and does not necessarily represent the official views of NASA or the NSF.Research News & Publications Office
Writer: Abby Robinson
Abby Robinson | Newswise Science News
Mountain glaciers shrinking across the West
23.10.2017 | University of Washington
Climate change weakens Walker circulation
20.10.2017 | MARUM - Zentrum für Marine Umweltwissenschaften an der Universität Bremen
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
23.10.2017 | Event News
17.10.2017 | Event News
10.10.2017 | Event News
23.10.2017 | Life Sciences
23.10.2017 | Automotive Engineering
23.10.2017 | Event News