Floods are the most common natural hazard and have also proven to be the deadliest and costliest of all natural disasters in history. Individual floods have killed upwards of a million people in China on several occasions, and cause billions of dollars of damage annually in different parts of the world. The risk of flooding increases with time as many countries are allowing settlements on floodplains and even encouraging commercial and residential growth on floodplains known to experience floods at frequencies of every several to every couple of hundred years. As world population continues to grow and people move into harm's way on floodplains, this problem will only worsen. Further, as the climate changes, some areas will experience more rainfall while others experience drought, so areas that may be relatively safe on floodplains now may be frequently inundated with floodwaters in the near future. Development of floodplains should not proceed without proper scientific analysis of the risks. in most cases floodplains should be preserved as natural areas or used for farming, but should not be the sites of major commercial or residential development.
Several kinds of floods affect different areas, act on different timescales, and present different types of hazards. Floods associated with hurricanes and tidal surges in coastal areas can cause extreme damage during these coastal storms. Rare, large thunderstorms in mountains and canyon territory typically cause a second type of flood, known as a flash flood. These floods can move into areas as a mud- and debris-laden wall of water, wiping out buildings and towns within a few seconds to minutes. Prolonged rains over large drainage basins cause a third category of floods, called regional floods. A final type of flood occurs in areas where rivers freeze over. In cold climate zones the annual spring breakup can cause severe floods, initiated when blocks of ice jam up behind islands, beneath bridges, or along river bends. These ice dams can create severe floods, causing the high spring waters to rise quickly, bringing the ice-cold waters into low-lying villages on floodplains. When ice dams break up, the force of the rapidly moving ice is sometimes enough to cause severe damage, knocking out bridges, roads, and homes. Ice-dam floods are fairly common in parts of New England, including New Hampshire, Vermont, and Maine. They are also common across much of Alaska and Canada, but the floodplains in these areas tend to be less developed so the floods pose fewer hazards to humans.
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This work on 2012 will attempt to note them allfrom the concepts andinvolvement by the authors of the Bible and its interpreters and theprophecies depicted in both the Hopi petroglyphs and the Mayan calendarto the prophetic uttering of such psychics, mediums, and prophets asNostradamus, Madame Blavatsky, Edgar Cayce, and Jean Dixon.