Temperature and Solar Radiation

The heat required to change water from a liquid to vapor is obtained from the sun. Solar heat increases the temperature of the Earth's surface and the air surrounding it. Evaporation of water occurs at a faster rate if both the evaporating surfaces -- such as seas, lakes, rivers, soil or vegetation -- and the air surrounding them have a higher temperature.

Wind Flow and Air Humidity

On a hot day, air close to the evaporating surface is saturated with moisture quickly. If the day is hot and windy, hot, dry air replaces the moisture-laden air quickly, thus increasing the rate of evaporation. Decreased evaporation occurs if humid air surrounds the evaporating surface and dry air does not replace it.

Evaporation from Water

Evaporation occurs at a lower rate from oceans than from fresh water surfaces due the presence of salts. Another factor affecting the rate of evaporation from a water body is its depth. Deep waters absorb more heat in the summer, warming water to a greater depth. This reduces the rate of evaporation.

Evaporation From Soil

Evaporation is faster from soil that is moist and surrounded by dry air. It is also faster from barren land than from land covered with vegetation. Air, humidity levels, wind, temperature and solar radiation all affect the rate of evaporation from soil.