Water Resources Chapter 4 PDF

CHAPTER 4 Water Resources Water Resources Objectives Identify the various water resources on Earth Recognize how water is distributed on Earth Suggest ways of conserving and protecting water resources Question 89% to Ponder: Significance of Agriculture Industry How...

CHAPTER 4 Water Resources Water Resources Objectives Identify the various water resources on Earth Recognize how water is distributed on Earth Suggest ways of conserving and protecting water resources Question 89% to Ponder: Significance of Agriculture Industry How is water cycled through the different components of Earth? Hydrologic cycle: movement of water around Earth’s surface and its subsystems Evaporation liquid water changes to vapor It occurs in the ocean, surface water bodies, vegetation, and soil. About 80% of water vapor in the atmosphere evaporates from the ocean. Transpiration is the evaporation of water from the leaves and stems of plants, which contributes about 10% of the water vapor in the atmosphere. Sublimation solid to the gaseous state without its becoming liquid In high altitudes, ice can directly transform into water vapor Condensation The water vapor enters the atmosphere and moves with the flowing air. As the air rises, it cools and slows down the movement of water molecules. This allows condensation, the change from vapor into liquid or solid, to occur. Water droplets group together and form clouds. Precipitation When water droplets or ice crystals in the clouds become large and heavy, precipitation occurs. Precipitation transfers water from the atmosphere to Earth's surface in liquid or solid form as rain, snow, or hail. Earth’s Water Budget: total amount of water in the planet Residence time: average length of time spent by water molecule in the reservoir.