4.7 Article

Northern Hemisphere Winter Air Temperature Patterns and Their Associated Atmospheric and Ocean Conditions

Journal

JOURNAL OF CLIMATE
Volume 33, Issue 14, Pages 6165-6186

Publisher

AMER METEOROLOGICAL SOC
DOI: 10.1175/JCLI-D-19-0533.1

Keywords

-

Funding

  1. National Natural Science Foundation of China [41705054]
  2. Natural Science Foundation of Jiangsu Province [BK20170942]
  3. General Program of Natural Science Research of Jiangsu Province University [17KJB170012]
  4. Startup Foundation for Introducing Talent of NUIST [2016r051]
  5. Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)
  6. China Scholarship Council [201808320137]
  7. National Science Foundation [AGS-1353740, OISE-1743738]
  8. U.S. Department of Energy's Office of Science [DE-SC0012602]
  9. U.S. National Oceanic and Atmospheric Administration [NA15OAR4310086, NA18OAR4310425]

Ask authors/readers for more resources

The Northern Hemisphere (NH) has experienced winter Arctic warming and continental cooling in recent decades, but the dominant patterns in winter surface air temperature (SAT) are not well understood. Here, a self-organizing map (SOM) analysis is performed to identify the leading patterns in winter daily SAT fields from 1979 to 2018, and their associated atmospheric and ocean conditions are also examined. Three distinct winter SAT patterns with two phases of nearly opposite signs and a time scale of 7-12 days are found: one pattern exhibits concurrent SAT anomalies of the same sign over North America (NA) and northern Eurasia, while the other two patterns show SAT anomalies of opposite signs between, respectively, NA and the Bering Sea, and the Kara Sea and East Asia (EA). Winter SAT variations may arise from changes in the SOM frequencies. Specifically, the observed increasing trends of winter cold extremes over NA, central Eurasia, and EA during 1998-2013 can be understood as a result of the increasing occurrences of some specific SAT patterns. These SOMs are closely related to poleward advection of midlatitude warm air and equatorward movements of polar cold airmass. These meridional displacements of cold and warm airmasses cause concurrent anomalies over different regions not only in SAT but also in water vapor and surface downward longwave radiation. Anomalous sea surface temperatures in the tropical Pacific, midlatitude North Pacific, and North Atlantic and anomalous Arctic sea ice concentrations also concur to support and maintain the anomalous atmospheric circulation that causes the SAT anomalies.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available