Install and launch Google Earth and zoom to Hoover Dam. Zoom outa bit to see the reservoir, and explore the region at yourpleasure. Identify the approximate coordinates and relativelocation with respect to Phoenix, Arizona.

Using textbook figures 5.9 and 5.10, examine the precipitationand potential evapotranspiration in the area.

1. What is the approximate annual precipitation (P) andpotential evapotranspiration (PET) in the area? Report approximatenumbers in cm. You must read from the same spot to the extentpossible. Alternatively, you may answer by using different, butcredible sources and revealing them.

P: ____________cm

PET: ___________cm

2. If you assume that there is no inflow to or outflow fromthe reservoir, how will the water level change per year? Providethe magnitude (in cm) and explain why you answered as such. Youmust explain based on correct understanding of PET and actualevapotranspiration. 

140 130 50- 30 Phoenix 110 Hudson Bay Toronto. Gulf of Mexico 90 5.9 Precipitation (PRECIP) in North America-the water supply 60 0 ATLANTIC OCEAN 200 ANNUAL PRECIPITATION in. 200 and over 150-199 100-149 50-99 25-49 Under 25 400 MILES cm 0 200 400 KILOMETERS Tropic of Cancer 70 80 and over 60-79 40-59 20-39 10-19 Under 10