我国进入拉尼娜状态，今年冬天到底是冷还是热？

Group 1 - The article discusses the current La Niña phenomenon, which indicates a significant cooling of sea surface temperatures in the eastern and central equatorial Pacific, with China entering a La Niña state as of October this year [2][3]. - La Niña status is defined by the NINO 3.4 index falling below -0.5°C, while a La Niña event requires this condition to persist for five consecutive months [5][6]. - The article highlights that La Niña can lead to increased climate anomalies, with historical occurrences of "double La Niña" events noted in 2000, 2011, and 2021, which have been linked to extreme weather patterns [7]. Group 2 - Experts predict that while a double La Niña event is unlikely this winter, the ongoing La Niña status may still influence China's climate, particularly with a higher probability of reduced precipitation in southern regions [8][10]. - The article mentions that La Niña is often associated with colder winters, but this year may not follow that trend, as the overall temperature is expected to be close to or slightly above normal, with significant fluctuations [11]. - The potential for winter-spring droughts in eastern and southern China is highlighted, with predictions of increased cold air activity leading to temperature swings [10][11].