唠“科”话｜体感入冬、气象入冬、节气立冬，冬天到底来了没有？

Core Viewpoint - The onset of winter has been perceived earlier this year in northern China, particularly in Shanxi province, due to a significant drop in temperatures and continuous rainy weather since October, leading to early heating supply in Taiyuan [1][4]. Group 1: Weather Conditions - Northern regions of China, including Shanxi, have experienced continuous rainy weather and a sharp decline in temperatures since October [1]. - Taiyuan began its heating supply on October 19, more than ten days earlier than the same period last year [1]. - The minimum temperature in southern Beijing dropped below freezing on October 20, prompting public comments about an abrupt transition to winter [1]. Group 2: Meteorological Definitions - The term "入冬" (entering winter) is defined meteorologically as the first day when the sliding average temperature falls below 10 degrees Celsius [3]. - "立冬" (Beginning of Winter) and "冬至" (Winter Solstice) are traditional solar terms, with "立冬" fixed around November 7 or 8, and "冬至" marking the shortest day of the year [3]. Group 3: Perception of Cold - Residents in Taiyuan report feeling a stark cold, with comments on the biting wind and sudden temperature drop [4]. - Meteorological experts indicate that while some areas may feel like winter has arrived, actual winter conditions are not met in Taiyuan, where temperatures are expected to remain above 10 degrees Celsius in the coming days [5]. - The discrepancy between perceived and actual temperatures is attributed to factors such as wind speed, humidity, and sudden changes in weather patterns, leading to a psychological feeling of "winter" despite meteorological definitions [6].