water is a kind of substance & water absorbs solar energy in the water cycle & if a substance absorbs solar energy then that substance will increase in temperature ->  water absorbing solar energy will increase in temperature  water absorbing solar energy will increase in temperature & temperature is a measure of heat energy ->  water absorbing solar energy will increase in heat energy  evaporation means a substance changes from a liquid into a gas by increasing heat energy & water is a kind of substance ->  evaporation of water is when water changes from a liquid into a gas by increasing heat energy  water absorbing solar energy will increase in heat energy & evaporation of water is when water changes from a liquid into a gas by increasing heat energy ->  water absorbing solar energy will cause the evaporation of water  water absorbing solar energy will cause the evaporation of water & the sun is a source of solar energy called sunlight -> in the water cycle the sun has the role of causing evaporation