一、如何理解“时”首先，任何一个天气系统都是大气环流中相对独立的系统，其生存时间一般较短，教学中应突出因时而异。如长江中下游地区，冬季频繁受到冷锋南下侵袭，出现大风低温雨雪天气；５月～６月又受准静止锋影响，常为阴雨连绵的“梅雨”天气；７月～８月则受副热带 First, how to understand the “time” First of all, any weather system is a relatively independent system in the atmospheric circulation, its survival time is generally shorter, the teaching should highlight the time difference. For example, in the middle and lower reaches of the Yangtze River, winters are frequently attacked by cold fronts in the south, with strong winds, low temperatures, rain, and snow; from May to June, they are affected by quasi-static fronts, often rainy “Meiyu”, and from July to August, they are subject to subtropical conditions.