Impacts of Western Disturbances on Wintertime Precipitation Over the Southeastern Tibetan Plateau. Issue 7 (28th March 2022)

• Record Type: Journal Article
• Authors: Qiu, Tianpei; Huang, Wenyu; Wright, Jonathon S.; Yang, Zifan; Wang, Bin
• Is Part Of: Journal of geophysical research. Volume 127:Issue 7(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-03-28
• Subjects: western disturbances -- wintertime precipitation -- Tibetan Plateau -- circumglobal teleconnection; Atmospheric physics -- Periodicals; Geophysics -- Periodicals; 551.5
• DOI: 10.1029/2021JD035789
• Languages: English
• ISSNs: 2169-897X

Abstract

Abstract: In this work, we examine the impacts of wintertime western disturbances (WDs) on precipitation over the southeastern Tibetan Plateau (SETP) during 1979–2017. Most WDs initially formed within the central Himalayas and dissipated over southeastern China and its neighboring seas. All extreme precipitation days over the SETP region during this period were linked to WDs, often when a WD center entered the region about 10° west of the SETP. Significant warm temperature anomalies over the SETP region preceding WD arrival favored moisture accumulation there. During the passage of WDs, both strong updrafts along the eastern edge of the WD and rapid decreases in temperature over the SETP (linked to WD‐associated cold anomalies below 300 hPa) favored the occurrence of wintertime precipitation over the SETP region. WD strength and moist static energy variations over the SETP region were key factors affecting the intensity of WD‐induced precipitation, while the size and latitudinal position of the WD played minor roles. The relatively strong WDs that produced extreme precipitation days over the SETP mainly originated above the eastern Mediterranean Sea, northern Arabian Peninsula, and Iranian Plateau. A distinct transition of the circumglobal teleconnection pattern modulated the generation of strong‐intensity WDs within these major genesis regions, as well as their eastward propagation and the generation of extreme precipitation over the SETP region. Key Points: All wintertime extreme precipitation days over the southeastern Tibetan Plateau (SETP) occurred in tandem with western disturbances (WDs) Most WDs with extreme precipitation originated in a band extending from the Eastern Mediterranean to the Iranian Plateau The circumglobal teleconnection modulated the effects of WDs on precipitation over the SETP