Toggle Main Menu Toggle Search

Open Access padlockePrints

The Karakoram/Western Tibetan Vortex: seasonal and year-to-year variability

Lookup NU author(s): Dr Xiaofeng Li, Professor Hayley Fowler, Dr Nathan Forsythe, Dr Stephen Blenkinsop, Dr David Pritchard

Downloads


Licence

This work is licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0).


Abstract

The “Karakoram Vortex” (KV), hereafter also referred to as the “Western Tibetan Vortex”, (WTV) has recently been recognized as a large-scale atmospheric circulation system related to warmer (cooler) near-surface and mid-lower troposphere temperatures above the Karakoram in the western Tibetan Plateau (TP). It is characterized by a deep, anti-cyclonic (cyclonic) wind anomaly associated with higher (lower) geopotential height in the troposphere, during winter and summer seasons. In this study, we further investigate the seasonality and basic features of the WTV in all four seasons, and explore its year-to-year variability and influence on regional climate. We find the WTV accounts for the majority of year-to-year circulation variability over the WTP as it can explain over 50% (R2≥0.5) variance of the WTP circulation on multiple levels throughout the troposphere, which declines towards the eastern side of the TP in most seasons. The WTV is not only more (less) active but also has a bigger (smaller) domain area, with a deeper (shallower) structure, in winter and spring (summer and autumn). We find that the WTV is sensitive to both the location and intensity of the Subtropical Westerly Jet (SWJ), but the relationship is highly dependent on the climatological mean location of SWJ axes relative to the TP in different seasons. We also show that the WTV significantly modulates surface and stratospheric air temperatures, north-south precipitation patterns and total column ozone surrounding the western TP. As such, the WTV has important implications for the understanding of atmospheric, hydrological and glaciological variability over the TP.


Publication metadata

Author(s): Li X-F, Fowler HJ, Forsythe N, Blenkinsop S, Pritchard D

Publication type: Article

Publication status: Published

Journal: Climate Dynamics

Year: 2018

Volume: 51

Issue: 9-10

Pages: 3883–3906

Print publication date: 01/11/2018

Online publication date: 21/02/2018

Acceptance date: 02/02/2018

Date deposited: 13/02/2018

ISSN (print): 0930-7575

ISSN (electronic): 1432-0894

Publisher: Springer

URL: https://doi.org/10.1007/s00382-018-4118-2

DOI: 10.1007/s00382-018-4118-2


Altmetrics

Altmetrics provided by Altmetric


Actions

Find at Newcastle University icon    Link to this publication


Share