Warm-up Turn in old warm-up sheet to the bin Where is water located on Earth? *Chapter 9 Study Guide due next Friday (1/11)

Water Basics

Water Cycle The water cycle is the continuous movement of Earth’s water from the ocean to the atmosphere to the land and back to the ocean.

Water Cycle

The processes of the Water Cycle Infiltration, condensation Evaporation Condensation Transpiration Precipitation

rain, snow, sleet or hail from clouds onto Earth’s surface. Precipitation rain, snow, sleet or hail from clouds onto Earth’s surface.

Infiltration downward movement of water through the pores and other spaces found in soil

Condensation takes place when water vapor cools and changes into water droplets that form clouds in the atmosphere

Runoff precipitation that flows over land into streams and rivers. This water usually enters oceans

takes place when water from Earth’s surface changes into water vapor Evaporation takes place when water from Earth’s surface changes into water vapor

Transpiration evaporation of water from leaves of plants causing the uptake of water from roots in the soil

Watershed- A region of land where water flows down into a specified body, such as a river, lake, sea, or ocean; or drainage basin. Tributaries – streams that flow into other streams A divide is a high land area that separates one watershed from another.

Questions to Ponder Where is water located on earth? http://ga.water.usgs.gov/edu/earthwherewater.html

World’s Freshwater Resources http://www.bgr.bund.de/EN/Gemeinsames/UeberUns/ueberuns_node_en.html

Questions to Ponder Where is water located on earth? What is its chemical structure? Where do we fit in? http://ga.water.usgs.gov/edu/earthwherewater.html

Why Do Organisms Need Water? Most metabolic processes require water Water is the “universal solvent” – stuff can dissolve in it including food and waste products.

Questions to Ponder Where is water located on earth? What is its chemical structure? Where do we fit in? http://ga.water.usgs.gov/edu/earthwherewater.html

Runoff Forms of precipitation On ground: evaporate, soak into ground, snow/glacier, or runoff Runoff may: evaporate, soak, freeze/glacier, or runoff into river, lake or ocean

Conditions to Soak (Infiltration) Vegetation – slows down runoff Rate of Precipitation – time to soak Soil Composition – large enough pores (spaces) with room for water Slope – erosion on steeper slopes

A Bit about Soil Sand (coarse particle size), silt (medium), clay (very fine) and organic matter (humus) Which soil type would drain the fastest? Why?

Water Quality The amount of dissolved material (solution) is monitored for water quality PPM – parts per million Pollution huge problem from road runoffs, sewage spills, pesticides runoffs from home and commercial land http://ga.water.usgs.gov/edu/waterquality.html

Human Activities that Impact the Water Cycle Use of toxic chemicals in agriculture and manufacturing and runoff from chemical fertilizers and pesticides can pollute surface water or seep into the ground to contaminate groundwater Clear-cutting forests reduces the amount of water plants return to the atmosphere by transpiration.