January northern hemisphere circumpolar vortex variability and its relationship with hemispheric temperature and regional teleconnections

✍ Scribed by Robert V. Rohli; Kalyn M. Wrona; Maurice J. Mchugh

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 663 KB
• Volume: 25
• Category: Article
• ISSN: 0899-8418
• DOI: 10.1002/joc.1204

✦ Synopsis

Variability in the hemispheric-scale atmospheric circulation can be directly linked to variations in surface environmental features, such as temperature, precipitation, salinity of water bodies, and pollutant transport. One indicator of the behavior of the hemispheric-scale circulation is the circumpolar vortex (CPV). This research utilizes a geographic information system approach to characterize variability in the Northern Hemispheric (NH) CPV. Specifically, the area, shape, and centroid of the January NHCPV are analyzed for 1959-2001 because it may provide insight about relationships between hemispheric-scale circulation and global temperature change. We also use a new means of characterizing the hemisphericscale circulation using a 'circularity ratio' (R c ). Results suggest that the January NHCPV has exhibited no long-term trends in area or shape, and that the mean centroid is positioned at approximately 85.3 °N, 178.0 °W. Regional patterns emerge, which suggest that the area and circularity are associated with variability in surface temperature and moist static energy. Furthermore, the area of the January NHCPV is associated with variability in the Arctic Oscillation, while the shape is tied to variability in the Pacific-North American teleconnection pattern. These results will facilitate understanding of the relationship between hemispheric-scale circulation, regional circulation, and local temperatures.