The Hydrosphere all of the water on or near the Earth’s surface covers almost 75% of the Earth’s surface includes water in the oceans, lakes, rivers, wetlands, polar ice caps, soil, rock layers beneath Earth’s surface, and clouds

The Water Cycle water cycle - continuous movement of water from the ocean to the atmosphere to the land and back to the ocean evaporation - change of a substance from a liquid to a gas condensation - change of state from a gas to a liquid precipitation – water in the form of rain, snow, sleet, and hail

The Water Cycle

Estimate Where is most water located? If one liter represented all the water on earth, how much would be ocean water?

Estimate How much of the remaining water (Earth’s freshwater ) is frozen in ice caps and glaciers? How much of the remaining water is available for human use?

Earth’s Oceans all oceans are connected - world ocean regulates Earth’s temp – absorbs and reflects heat

Ocean Water salinity - amount of dissolved salts in a given amount of liquid most salt dissolved in ocean is sodium chloride (NaCl)

The Oceans Three parts: Surface zone: warmest, upper-most, 0-350m deep. Thermocline: Temperature drops quickest. Middle layer m. Deep Zone: 750m-bottom. Temps near freezing (2ºC).

Temperature Zones surface of the ocean is warmed by the sun depths of the ocean (where sunlight never reaches) are very cold

Fresh Water most of the fresh water is locked up in icecaps and glaciers also found in lakes, rivers, wetlands, the soil and atmosphere

Ground water Rain and melting snow sink into the ground and run off the land trickles down through the ground and collects as groundwater makes up only 1 percent of all the water on Earth - fulfills the human need for fresh drinking water, and supplies agricultural and industrial need

Aquifers rock layer that stores and allows the flow of groundwater