The Influence of Interdecadal Changes in Boreal Winter Teleconnections Around the 1980s on Planetary Waves and Stratospheric Sudden Warmings. Issue 19 (4th October 2021)

• Record Type: Journal Article
• Authors: Li, Yuanpu; Wen, Zhiping
• Is Part Of: Journal of geophysical research. Volume 126:Issue 19(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-10-04
• Subjects: teleconnections -- SSW -- interdecadal change; Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1029/2021JD035341
• Languages: English
• ISSNs: 2169-897X

Abstract

Abstract: This study investigated the influence of the interdecadal changes in the Pacific‐North America (PNA) and Western Pacific (WP) teleconnections on the planetary waves and stratospheric sudden warmings (SSWs), based on the National Center for Environmental Prediction reanalysis and Japanese 55‐year reanalysis. Before the 1980s, there were more negative PNA & negative WP combinations (−PNA&−WP), and after the 1980s, there were more +PNA&+WP. +PNA&−WP and −PNA&+WP had no significant interdecadal changes before and after the 1980s. The interdecadal changes in the teleconnection combinations may be related to the Pacific Decadal Oscillation (PDO). During +PNA&+WP (−PNA&−WP), the planetary waves with wavenumber 1 have the maximum (minimum) wave energy and propagating more (less) to the stratosphere, causing a greater (lesser) frequency of SSWs. Thus, the interdecadal changes in the teleconnection combinations are one of the important factors which could contribute to the possible increase in SSWs after the 1980s. Since there are no satellite observations on the stratosphere before 1979, there are still many uncertainties in the interdecadal changes in SSWs. Plain Language Summary: Stratospheric sudden warmings (SSWs) are rapid warming processes occurring in the stratosphere in winter. In the northern hemisphere, SSWs mitigate springtime ozone depletion and have potential effects on tropospheric weather. Nevertheless, the number of SSWs recorded in each decade is variable, and these interdecadal changes give rise to changes in SSW impacts. At the same time, the Pacific‐North America (PNA) and Western Pacific (WP) patterns are the most prominent modes of low frequency variability in the Northern Hemisphere. Before the 1980s, there were more −PNA&−WP (negative PNA and negative WP combinations), and after the 1980s, there were more +PNA&+WP. The interdecadal changes in the teleconnection combinations may be related to the Pacific Decadal Oscillation, which is an important decadal signal in the climate system. +PNA&+WP and −PNA&−WP have a significant influence on SSWs, since more (less) planetary waves enter the stratosphere during +PNA&+WP (−PNA&−WP). The interdecadal changes in the teleconnection combinations may have an important contribution to the possible increase in SSWs after the 1980s. Key Points: The teleconnection combinations of +PNA&+WP and −PNA&−WP had significant interdecadal changes around the 1980s The interdecadal changes in +PNA&+WP and −PNA&−WP may be related to the Pacific Decadal Oscillation The interdecadal changes in +PNA&+WP and −PNA&−WP could contribute to the possible increase in SSWs after the 1980s