Water Cycle: Evaporation and Condensation

Evaporation

• The process by which water is converted from its liquid form to water vapor
• Occurs on the surface of the Earth, such as oceans, lakes, and rivers, as well as on land, including plants and soil
• Energy from the sun heats up the water, increasing its temperature and turning it into vapor
• Evaporation is increased by:
  • Higher temperatures
  • Lower air pressure
  • Higher humidity
  • Wind

Condensation

• The process by which water vapor in the air is converted back into liquid water
• Occurs when the air reaches its dew point, which is the temperature at which the air becomes saturated with water vapor and can no longer hold any more moisture
• Condensation forms:
  • Clouds
  • Fog
  • Dew
  • Frost
• Condensation is increased by:
  • Lower temperatures
  • Higher humidity
  • Presence of condensation nuclei (e.g. dust, salt, and pollutants)

Precipitation

• The process by which water droplets in the atmosphere fall to the ground
• Forms of precipitation include:
  • Rain
  • Snow
  • Sleet
  • Hail
• Precipitation occurs when:
  • The air is cooled to its dew point
  • The air is saturated with water vapor
  • The water droplets in the clouds become too heavy to remain suspended
• Factors that influence precipitation include:
  • Temperature
  • Humidity
  • Wind patterns
  • Topography

Runoff

• The process by which water flows over the land surface, forming streams, rivers, and lakes
• Occurs when the ground is saturated with water and can no longer absorb any more
• Types of runoff include:
  • Surface runoff
  • Groundwater runoff
• Factors that influence runoff include:
  • Topography
  • Soil type and permeability
  • Land use and land cover
  • Precipitation intensity and duration

Transpiration

• The process by which plants release water vapor into the air
• Occurs through the plant's roots, stems, and leaves
• Transpiration is an important part of the water cycle, as it helps to:
  • Recycle water back into the atmosphere
  • Regulate the Earth's temperature
  • Support plant growth and development
• Factors that influence transpiration include:
  • Temperature
  • Humidity
  • Light intensity
  • Soil moisture and availability

Evaporation

• Water is converted from liquid to water vapor on the surface of the Earth, including oceans, lakes, rivers, plants, and soil
• Energy from the sun heats up the water, increasing its temperature and turning it into vapor
• Evaporation is increased by higher temperatures, lower air pressure, higher humidity, and wind

Condensation

• Water vapor in the air is converted back into liquid water when the air reaches its dew point
• Condensation forms clouds, fog, dew, and frost
• Condensation is increased by lower temperatures, higher humidity, and the presence of condensation nuclei (e.g. dust, salt, and pollutants)

Precipitation

• Water droplets in the atmosphere fall to the ground, forming rain, snow, sleet, and hail
• Precipitation occurs when the air is cooled to its dew point, saturated with water vapor, and the water droplets in the clouds become too heavy to remain suspended
• Factors that influence precipitation include temperature, humidity, wind patterns, and topography

Runoff

• Water flows over the land surface, forming streams, rivers, and lakes, when the ground is saturated with water
• Types of runoff include surface runoff and groundwater runoff
• Factors that influence runoff include topography, soil type and permeability, land use and land cover, and precipitation intensity and duration

Transpiration

• Plants release water vapor into the air through their roots, stems, and leaves
• Transpiration helps to recycle water back into the atmosphere, regulate the Earth's temperature, and support plant growth and development
• Factors that influence transpiration include temperature, humidity, light intensity, and soil moisture and availability