Phys.org February 27, 2023
Researchers in Japan investigated the structure and dynamics of two distinct patterns. They showed that the winter climate over East Asia is influenced by two teleconnection patterns, the western Pacific pattern, and the Southeast Asia-Japan pattern. Using meteorological data for winters from 1974 to 2021 they established the baseline climate and analyzed anomalous departures from that baseline. In the first half of the 2020/2021 winter season, an anticyclonic circulation anomaly appeared over the southeastern Tibetan Plateau, and a corresponding cyclonic anomaly occurred over northern Japan. This pattern was associated with enhanced convection over the South China Sea toward the Indian Ocean. But in the second half of this winter season, the anticyclonic anomaly shifted to southern Japan. The resulting changes in the flow of cold air brought warmer-than-normal conditions to East Asia, and the enhanced convection also moved east toward the Philippine Sea and caused changes in the East Asian winter monsoon. According to the researchers closer analysis of interactions of air circulation between the tropics and higher-latitude regions will further improve understanding of these teleconnection patterns and lead to better seasonal forecasting…read more. Open Access TECHNICAL ARTICLEÂ
Time series of 5-day running mean air temperature anomaly at 850 hPa over East Asia… Credit: Journal of the Meteorological Society of Japan. Ser. II (2022)Â