Water Vapor in the Atmosphere

Water vapor enters the atmosphere by evaporation from oceans, smaller bodies of water (rivers, lakes, etc.), moisture from the ground, and transpiration of plants.

The amount of water that enters the atmosphere and the rate at which evaporation occurs from an area depends on several factors including:

  • The temperature of the liquid water on the surface
  • How much liquid water is available on the surface
  • How much water vapor is already in the air above the surface
  • The temperature of the air
  • The wind speed