Characteristics and possible influencing factors of Siberia-Qinghai-Tibet Plateau dipole temperature anomaly in boreal winter
LI Gaolong
LI Chun
Abstract：Based on observational data and multi-source reanalysis materials,this study explores the characteristics and possible influencing factors of the Siberia-Qinghai-Tibet Plateau dipole surface temperature anomaly pattern during the winter(December-February of the following year)from 1981 to 2023.The research shows the following results.(1)The Siberia-Qinghai-Tibet Plateau dipole surface temperature anomaly is observed over Asia in winter.The Siberia cold anomaly is primarily driven by cold advection resulting from weakened sub-polar westerlies under the influence of an anomalous low-pressure system over Lake Baikal.The Qinghai-Tibet Plateau warm anomaly stems from the increased short-wave radiation due to reduced cloud cover controlled by a persistent high-pressure anomaly,with additional amplification via ice/snow-albedo feedback.(2)In late autumn(October-November),the low sea ice concentration in the Barents-Kara Sea triggers an abnormal high-pressure system in the upper atmosphere by thermal action and maintains it until winter.Subsequently,the Rossby wave energy spreads to the south,which is conducive to the formation of a low-pressure anomaly over Lake Baikal.This is conducive to the occurrence of the Siberia cold anomaly and ultimately helps to form the positive phase of the Siberia-Qinghai-Tibet Plateau dipole temperature anomaly.However,the situation is the opposite when there is high sea ice concentration.(3)The positive(negative)winter precipitation anomaly over western Mediterranean Sea-northeastern Atlantic Ocean excites a negative(positive)upper-level wave source,which in turn triggers both sub-polar and sub-tropical wave trains.Contrasting pressure anomalies—low pressure(high pressure)near Lake Baikal and high pressure(low pressure)over the Qinghai-Tibet Plateau,promote the development of the positive(negative)phase of the Siberia-Qinghai-Tibet Plateau dipole temperature anomaly.This study clarifies the regulatory effects of the thermal-dynamic coupling between sea ice and the atmosphere and the remote propagation of wave energy on the Siberia-Qinghai-Tibet Plateau dipole temperature anomaly,providing a theoretical basis for predicting the interannual variations of winter temperatures in Siberia and Qinghai-Tibet Plateau.
Keywords：Siberia-Qinghai-Tibet Plateau dipole surface temperature anomalysea ice over the Barents-Kara seaprecipitation over western Mediterranean Sea-northeastern Atlantic OceanRossby wave trainstemperature advection
Publication Date：2026-02-28
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：11( 106-116 )