赤道中东太平洋已进入拉尼娜状态 我国今冬冷暖起伏大

Core Viewpoint - The recent monitoring by the National Climate Center indicates that the equatorial central and eastern Pacific has entered a La Niña state, which typically leads to lower winter temperatures in China. Public interest has surged regarding the potential for a "double La Niña" this winter and whether it will be a cold winter [1]. Group 1: Understanding La Niña - La Niña refers to a phenomenon where the sea surface temperatures in the equatorial central and eastern Pacific are abnormally cold. It is defined by the NINO 3.4 index, which indicates La Niña when the three-month average is less than or equal to -0.5°C [2]. - The current La Niña state is expected to persist until early 2026, but the likelihood of it developing into a full La Niña event is relatively low, making the occurrence of a double La Niña this winter unlikely [2]. Group 2: Climate Impact of La Niña - The occurrence of La Niña leads to significant global climate anomalies, particularly affecting China's climate. During La Niña winters, cold air from the north is more likely to move south, resulting in lower temperatures in central and eastern China [3]. - La Niña conditions can also lead to reduced precipitation in southern regions, increasing the risk of drought during the winter and spring [3]. - In the summer following a La Niña event, the position of the subtropical high in the western Pacific tends to shift northward, which can lead to increased rainfall in northern China but decreased rainfall in the Yangtze River basin, raising the risk of high temperatures and drought [3]. Group 3: Preparations for Winter - The forecast suggests that winter temperatures in China will be close to or slightly above the historical average, with significant fluctuations expected. Overall precipitation is predicted to be lower, particularly in southern regions [4]. - In northern areas, there may be risks of strong winds, severe cold, and heavy snowfall, which could impact agriculture and energy supply. Preparations for energy demand spikes and material reserves are recommended [4]. - Southern and eastern regions may face risks of winter-spring droughts due to higher temperatures and lower precipitation, necessitating improved water resource management and fire risk monitoring [4].