The role of the subtropical jet stream in spring rainfall in Northern Vietnam

Abstract

This paper employs statistical methods to investigate the role of the subtropical jet stream in spring rainfall. The research findings indicate that when the jet stream is strong and the westerly trough deepens, rainfall increases, and vice versa. The eastward movement of the jet stream at 500mb and 200mb levels shows that the stronger and deeper the jet stream, the slower its eastward displacement. Although the jet stream plays a minor role in causing spring rainfall in Northern Vietnam, its role in the region's convective processes leading to rainfall cannot be denied. The combination of the upper-level jet stream and weakened, eastward-shifting low-level cold air is the main cause of rainfall events during the spring in this area, with significant implications for Northern Vietnam.