when air is cooled to the point where it cannot hold anymore water it starts to rain. evaporation is a cooling processes because it cools the air. Evaporation is a cooling processbecause when liquid turns to gas, it needs more energy, and so it has to take that energy from its surroundings. The energy is in the form of heat, and when the heat energy leaves with theevaporating liquid, the surroundings get cooler. the sun is responsible for unequal hearing in the water cycle.