This paper investigates teleconnection patterns in the geopotential height field during Northern Hemisphere winter, focusing on recurrent spatial patterns that may indicate standing oscillations in planetary waves. The authors analyze a 15-year dataset of monthly mean sea level pressure and 500 mb height anomalies to identify and document these patterns. They find that the strongest teleconnection patterns resemble the leading eigenvectors of the correlation matrix. Four main teleconnection patterns are identified: the North Atlantic Oscillation (NAO), the North Pacific Oscillation (NPO), the zonally symmetric seesaw, and the Pacific/North American (PNA) pattern.
The NAO is characterized by a seesaw in winter temperatures between the Greenland-Labrador region and northwestern Europe, with a strong association with the strength of the climatological mean jet stream over the western Atlantic. The PNA pattern includes a north-south seesaw in the central Pacific and centers of action over western Canada and the southeastern United States. The zonally symmetric seesaw is a standing oscillation in the sea level pressure field with a node near 50°N latitude. The NAO and PNA patterns are strongly evident in both the primary and independent data sets.
The analysis reveals that the sea level pressure statistics are dominated by negative correlations between the polar region and temperate latitudes, while the 500 mb statistics show regional-scale patterns with a nearly equivalent barotropic structure. The NAO and PNA patterns are well supported by the analysis, and both share features such as influencing winter temperatures over the eastern United States and involving a seesaw between the depths of the Icelandic and Aleutian lows. The study also highlights the importance of these patterns in understanding long-range atmospheric teleconnections and their implications for weather forecasting.This paper investigates teleconnection patterns in the geopotential height field during Northern Hemisphere winter, focusing on recurrent spatial patterns that may indicate standing oscillations in planetary waves. The authors analyze a 15-year dataset of monthly mean sea level pressure and 500 mb height anomalies to identify and document these patterns. They find that the strongest teleconnection patterns resemble the leading eigenvectors of the correlation matrix. Four main teleconnection patterns are identified: the North Atlantic Oscillation (NAO), the North Pacific Oscillation (NPO), the zonally symmetric seesaw, and the Pacific/North American (PNA) pattern.
The NAO is characterized by a seesaw in winter temperatures between the Greenland-Labrador region and northwestern Europe, with a strong association with the strength of the climatological mean jet stream over the western Atlantic. The PNA pattern includes a north-south seesaw in the central Pacific and centers of action over western Canada and the southeastern United States. The zonally symmetric seesaw is a standing oscillation in the sea level pressure field with a node near 50°N latitude. The NAO and PNA patterns are strongly evident in both the primary and independent data sets.
The analysis reveals that the sea level pressure statistics are dominated by negative correlations between the polar region and temperate latitudes, while the 500 mb statistics show regional-scale patterns with a nearly equivalent barotropic structure. The NAO and PNA patterns are well supported by the analysis, and both share features such as influencing winter temperatures over the eastern United States and involving a seesaw between the depths of the Icelandic and Aleutian lows. The study also highlights the importance of these patterns in understanding long-range atmospheric teleconnections and their implications for weather forecasting.