地球大气圈和水圈互相渗透、互相影响，结为一对密不可分的自然系统。大气中所产生的冷、热、干、湿、风、云、雨、雪、霜、雾、雷、电等现象，无一不对地球水文状况产生直接或间接的影响。大气现象、水文状况超过人类所能忍受的程度，突破临界限度，使成为灾害，构成统一的气 The Earth’s atmosphere and hydrosphere infiltrate and interact with each other and become a pair of natural systems inseparable from each other. The phenomena of cold, heat, dryness, wetness, wind, cloud, rain, snow, frost, fog, thunder and electricity in the atmosphere all have a direct or indirect impact on the hydrological conditions of the earth. Atmospheric phenomena, hydrological conditions exceed the extent of humankind can break through the critical limits, so that a disaster, a unified gas