When water changes state, heat is exchanged between water and its surroundings. When water evaporates, heat is absorbed. When water condenses, heat is released. This heat is measured by calories. One calorie is the amount of heat required to raise the temperature of 1 gram of water 1C.Because the Heat is used to melt ice does not produce a temperature change, its referred to as latent heat. Latent heat means hidden.

It takes 80 calories to melt one gram of ice It takes 80 calories to melt one gram of ice. It takes about 540 to 600 calories to go from gas to liquid. To go from Gas to Solid (deposition) heat released 680 calories.

Four mechanisms that cause air to rise are (1) orographic lifting, where air is forced to rise over a mountainous barrier, (2) frontal wedging, where warmer, less dense air is forced over cooler, denser air along a front, (3) convergence, a pileup of horizontal air flow resulting in an upward flow, and (4) localized convective lifting, where unequal surface heating causes localized pockets of air to rise because of their buoyancy.