Relationship between the East Atlantic teleconnection pattern and the spring dust storm in northern China. Part‐I: Impacts of components of the atmospheric circulation over Eurasia on dust storm dynamic power—Spring gales

Abstract

Spring gale is a dynamic power for DSs (DSs), which presents a close connection with the DSs of northern China. Both display declining trends during the past 68 years . In this study, the influencing factors of spring gales and DSs around northern China and possible adjustment functions of the East Atlantic (EA) teleconnection pattern have been investigated. It was found that the major systems controlling spring gales include the North Polar vortex (NPV), mid-high-latitude blocking highs (BHs), air pressure status of the Tibetan Plateau (TP) over the Eurasian continent, India-Burma trough (IBT) and western Pacific subtropical high (WPSH). Under synthetic atmospheric circulation conditions of an enlarged NPV, lower air pressure over the TP, a strong IBT, and a southeastward-retreated WPSH, spring gales increase, and the frequency of DS occurrence is increased, and vice versa. Additionally, spring gales are also negatively affected by BHs. The most important is the Baikal BH, which has influence not only in previous seasons but also in the contemporary spring. Furthermore, the NPV and IBT have close negative correlation with the EA pattern, whereas the TP and WPSH have positive correlation with the EA pattern both in previous seasons and in the contemporary spring. A high-pitched EA pattern results in a strong western current north of Lake Baikal, which may prohibit the expansion of the NPV in the sector of northern China. A shrunk NPV means infrequent cold air attacks and decreased gales and DSs.