Global Evaporation and Precipitation Describing the amount of water that moves through the water cycle each year involves some very large numbers. For example, the water that evaporates from the ocean surface each year is about 502,800km while evaporation from land is about 74,200 km? To put this in perspective, only 1 km of water equals over 260 billion gallons! (An average swimming pool is only 10,000 gallons) When global atmospheric precipitation is measured, about 458,000 km"falls on the ocean while 119,000 km°falls on land. 1. Calculate the difference between the volume of water evaporating from and precipitating onto the oceans. Show your work 2. Calculate the difference between the volume of water evaporating from and precipitating onto the land. Show your work 3. Notice that more water evaporates from the oceans than falls on the oceans as precipitation. Also notice that the reverse is true on land. Explain why this is the case. Infiltration, Runoff, and Running Water When precipitation falls as rain onto the Earth's surface the water can soak Into the ground (Infiltration) where it may become part of the groundwater system. Water that does not infiltrate begins to flow across the ground surface as runoff, whether infiltration or runoff is dominant depends on many factors: the soil or rock type the water falls upon, the amount of vegetation present, the slope of the land surface (gradient), and the Intensity of precipitation. 4. Consider a hilly landscape covered with abundant vegetation (like the pine forests around Tyler, TX). How might such a landscape affect rates of infiltration and runoff? Explain. 5 Now considera ftat, dry, desert landscape as around El Paso, TX. How might such a landscape affect rates of Infiltration and runoff? Explain.