Water Cycle & Water in Ecosystems Pearson Education Dr. Jeffrey R. Corney, Managing Director of the University of Minnesota’s Cedar Creek Ecosystem Science Reserve

2-A) Earth’s entire freshwater supply makes up approximately what percentage of the total volume of all water found on Earth? a. 97% b. 33% c. 3.0% d. 1.0%

2-B) Of all of the volume of water found on Earth, the amount of freshwater that is readily accessible for human use makes up approximately what percentage of the total volume? a. 97% b. 33% c. 3.0% d. 1.0%

a. Almost all of it b. About half of it c. Less than a tenth of it 2-C) In the United States, approximately how much of our drinking water supply comes from groundwater aquifers? a. Almost all of it b. About half of it c. Less than a tenth of it d. None of it

Distribution of Water on Earth USGS USGS

Not Much Surface Freshwater on Earth! World’s surface freshwater supply just a drop in the bucket Of all the freshwater not locked up in ice caps or glaciers and not below the surface in groundwater aquifers, some 20% is in areas too remote for humans to access; and of the remaining 80%, about three-quarters comes at the wrong time and place – in monsoons and floods – and is not always captured for use by people. The remainder is about 0.08% of the total water on the planet.

Not Much Water on Earth! Spheres showing… LARGE BLUE SPHERE: All of Earth’s water, saline oceans and all freshwater, including within icecaps (sphere over western U.S., 860 miles in diameter). SMALL BLUE SPHERE: All of Earth’s liquid freshwater in the ground, lakes, swamps, and rivers (sphere over Kentucky, 169.5 miles in diameter). USGS & Woods Hole Oceanographic Institution

Where on Earth Is the Water?

Definition of a Watershed A watershed is the area of land where all of the water that is under it or drains off of it goes into the same place. John Wesley Powell, scientist geographer, put it best when he said that a watershed is: “that area of land, a bounded hydrologic system, within which all living things are inextricably linked by their common water course.” Watersheds come in all shapes and sizes. They cross county, state, and national boundaries. In the continental US, there are 2,110 watersheds. U.S. EPA

Great Lakes Watershed Environment Canada

Mississippi Watershed Watersheds.org Fourth largest basin in the world (1.2M sq. miles). Drains nearly 40% of the continental U.S. Travels 2,340 miles from Lake Itasca to Gulf of Mexico. Water retention from headwaters to Gulf is about 90 days.

a. Evaporation b. Transpiration c. Condensation d. Precipitation 2-D) As part of Earth’s hydrologic cycle water is extracted from soil by the roots of plants, transported through the plant, then released through the plant’s leaves back into the atmosphere through a process called: a. Evaporation b. Transpiration c. Condensation d. Precipitation e. Infiltration

a. Evaporation b. Transpiration c. Condensation d. Precipitation 2-E) As part of Earth’s water or hydrologic cycle a significant amount of water makes its way downward through soil and permeable rock to groundwater storage areas through a process called: a. Evaporation b. Transpiration c. Condensation d. Precipitation e. Infiltration

2-F) Match the following WATER RESOURCE terms with the definition that best describes it: Aquifer_____ Watershed_____ Surface runoff_____ Water table_____ Natural recharge_____ a. Precipitation that flows into streams and lakes b. Top of the zone of saturation c. Replenishment of groundwater by infiltration d. Water-saturated sand or gravel where groundwater flows e. Basin where all water drains into same bodies of water

The Water Cycle NOAA

Condensation SGU DEW POINT is the temperature below which the water vapor in a volume of humid air at a given constant barometric pressure will condense into liquid water .

Precipitation Rgee VSC CMMAP

Global Precipitation Pattern 80% of all precipitation falls over the oceans, so only 20% over land

Groundwater (Aquifer) Formation sand & Earthsci.org Precipitation (recharge) (soil moisture)

Groundwater Aquifers of the U.S. NOAA Ogallala

Upper Midwest Aquifers USGS

Groundwater & Surface Water USGS

Climate and Aquifer Recharge Moist Climate w/ Thick Vegetation & Soil Dry Climate w/ Sparse Vegetation & Thin Soil Earthsci.org

Groundcover and Aquifer Recharge

(Evapotranspiration) Temperature (Solar Radiation) Precipitation (Amount & Timing) Soil Moisture (Evapotranspiration)

Where Does the Precipitation Go? Evapotranspiration 67% Surface Runoff 29% Consumptive Use 2% Groundwater Outflow 2% U.S. Estimated Water Budget USGS

Evapotranspiration Wikipedia

Evaporation: Driven by Energy “Heat” UCF.edu Purdue.edu

Evaporation: Soil Moisture Conditions

Soil Moisture Holding Capacity

Transpiration of Water Through Plants Helicon

(Evapotranspiration) Temperature (Solar Radiation) Precipitation (Amount & Timing) Soil Moisture (Evapotranspiration)

Global Soil Moisture Balance IGBP/GAIM Water balance coefficient computed as the difference between annual precipitation and potential evapotranspiration.

Where on Earth Plants Thrive…or Not!

U.S. Temperature & Precipitation

U.S. “Pan” Evaporation Rates (a rough measure of Potential Evapotranspiration) Wikipedia NOAA

Soil Moisture Balance for the Midwest - + USDA USDA - + PRAIRIE FOREST

Soil Moisture & Three Biomes of MN Deciduous Forest Coniferous Forest Grassland MN DNR

Dr. Jeffrey R. Corney, Managing Director University of Minnesota Cedar Creek Ecosystem Science Reserve 2660 Fawn Lake Dr NE East Bethel, MN 55005 (763) 434-5131 www.cbs.umn.edu/cedarcreek jcorney@umn.edu