Comment: 24:59 - 26:12 (01:13)
Source: Annenberg/CPB Resources - Earth Revealed - 19. Running Water I: Rivers, Erosion and Deposition
Keywords: "James Sadd", "Mississippi River", river, flood, landscape, discharge, water, humans, civilization, "geologic hazard", "United States"
Our transcription: The power of running water extends far beyond the Mississippi.
Indeed, it is the dominant force shaping Earth's landscape.
The combined discharge of all of the rivers on Earth is only one ten-thousandth of one percent of all the water on this planet.
But few geologic processes have exerted a greater influence on human history and civilization.
Many of the world's great cities were first established as riverside settlement, and throughout their history, these cities have depended on the river for food, a water supply, and an avenue of transport and trade.
But like all natural systems, rivers undergo relatively rare, but extreme, events.
River flooding is a threat to nearly every nation on Earth.
In the United States, floods exact the greatest toll of any geologic hazard, causing billions of dollars in property damage and killing about a hundred people every year.
And this loss is modest when compared to the destruction in countries with primitive flood control systems, or the devastation in pre-industrial societies which were visited by floods without warning.
Geology School Keywords