Chapter 3 Section 3 OBJECTIVES: Identify major processes in water cycle. Describe properties of ocean water. Discuss factors that allow life in the biosphere. KEY TERMS: Water cycle Salinity Biosphere
The Hydrosphere All the water on or near Earth’s surface. Oceans, lakes, rivers, wetlands, polar ice caps, soil, and clouds.
The Water Cycle Continuous movement of water from Earth to atmosphere and back to Earth.
The Water Cycle - Evaporation Water continually evaporates from Earth. Majority of water evaporates from oceans. Transpiration – water released from plants.
The Water Cycle - Condensation Water vapor forms droplets on dust particles Particles form clouds (droplets collide to create larger, heavier drops)
The Water Cycle - Precipitation Drops of water fall to Earth as precipitation. Rain, snow, sleet, hail
The Water Cycle - Collection Water falls back to Earth and gathers in lakes, rivers, streams, oceans
Ocean Water - Salinity Salinity - amount of dissolved salt in a liquid. Lower in areas with lots of rain or where fresh water flows in to the sea. Higher where water evaporates rapidly (leaves salt behind).
Temperature Zones Why is the surface of the ocean warm and the depths of the ocean cold? Ocean surface is warmed by the sun. Depths of the ocean are very cold.
Global Temperature Regulator Oceans absorb and store solar radiation - regulates atmospheric temperatures. Oceans absorb and release heat slower than land Without regulation of temperatures life could not exist on Earth.
A Global Temperature Regulator Currents circulate warm water Causes land areas they flow past to have moderate climates.
Surface Currents Movements of water at or near the surface of the ocean. What drives (causes) these currents? Wind-driven (from global wind patterns).
Fresh Water Fresh water - water that contains insignificant amounts of salts. Most fresh water is in icecaps and glaciers.
Ground water Water in ground Replenished by rain and melting snow. 1% of water on Earth.
Aquifers A rock layer that stores and allows the flow of groundwater.
The Biosphere Area on Earth where life exists. Located on or near Earth’s surface Why is biosphere on or near Earth’s surface? Sunlight is available near the surface. Plants need sunlight to produce food most other organisms use plants and algae for food. Other Factors: Water, Moderate Temperatures
Energy Flow in the Biosphere Energy used by organisms is obtained in the biosphere. Organism dies, body decays and nutrients in it are available for other organisms. This flow of energy allows life on Earth to continue to exist.
Energy Flow in the Biosphere Matter does not enter or leave Earth but energy does energy comes from the sun. energy travels from plant to animal. energy is lost to space as heat.