The Dominant Intraseasonal Coupling Mode between the Stratosphere and Troposphere: Stratosphere-Troposphere Oscillation ...

• Main Authors: Shen, Xiaocen, Wang, Lin, Scasife, Adam A., Hardiman, Steven C., Xu, Peiqiang
• Format: Conference Object
• Language: English
• Published: GFZ German Research Centre for Geosciences 2023
• Subjects: Pacific; North Atlantic
• Online Access: https://dx.doi.org/10.57757/iugg23-3326; https://gfzpublic.gfz-potsdam.de/pubman/item/item_5019677

Changes in the stratospheric polar vortex (SPV) can remarkably impact tropospheric circulation. Based on the diagnosis of reanalysis data, this study finds that the location shift rather than the strength change dominates the intraseasonal variability of SPV. Further analysis suggests that it couples well with the tropospheric circulation, forming an intraseasonal stratosphere-troposphere oscillation (STO). The STO shows periodic westward propagation throughout its life cycle and has a deep structure extending from the troposphere to the stratosphere. It reflects the movement of the SPV toward North America, then North Pacific, Eurasia, and the North Atlantic, and causes significant changes in surface air temperature over North America and East Asia. The mechanism of the STO involves Rossby wave propagation between the troposphere and stratosphere and cross-scale interactions in the troposphere. Upward Rossby wave propagation from the troposphere over East Asia maintains the STO’s stratospheric component, ... : The 28th IUGG General Assembly (IUGG2023) (Berlin 2023) ...