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The Iowa flood of 2008 was a hydrological event involving most of the rivers in eastern Iowa beginning around June 8, 2008 and ending about July 1. Flooding continued on the Upper Mississippi River in the southeastern portion of the state for several more days. The phrase "Iowa's Katrina" was often heard.〔"(Editorial: Iowa's Katrina? Not if state does its part: Charity helps now, but eventually, state must pay )," Minneapolis Star Tribune, June 16, 2008, Retrieved June 22, 2008〕 The flooding included (from north to south, east to west), the Upper Iowa River, the Turkey, and the Maquoketa Rivers; outside of the Driftless Area, they include the catchments of the Wapsipinicon River and that of the Iowa River, to include the latter's major tributary, the Cedar River (and its significant tributaries); and the Skunk River in its various forks. The Des Moines River had some minor flooding, but floodwalls and levees for the most part held fast. The Upper Mississippi River which receives the outflow from all these rivers remained at flood stage. The flooding of Cedar Rapids and Iowa City were the most significant events. Recovery in particular for Cedar Rapids is considered to be a protracted and costly affair. For Iowa City, the level of damage was less than expected, but that of Cedar Rapids was greater than anticipated. In Iowa City, the campus of the University of Iowa was vulnerable, and serious flooding did occur there. President George W. Bush landed on Air Force One at The Eastern Iowa Airport on June 20. He toured on foot and by helicopter the Cedar Rapids and Iowa City region. On the same day, Senator John McCain made a stop in Columbus Junction.〔John Q, Lynch, "We're going to help you", ''Cedar Rapids Gazette'', June 20, 2008, p.1A〕〔Associated Press, "McCain tours flood-damaged Columbus Junction", ''Cedar Rapids Gazette'', June 20, 2008, p.1B〕 ==Origins== State Meteorologist Elwynn Taylor of Iowa State University said that the wet spring of 2008 was traceable to relatively warm and wet air over the winter. Taylor explained: "Fog in the winter is normally the result of a strong flow of warm, moist air from the Gulf of Mexico, which normally does not occur in the winter," he said. "Usually that occurs in March and April. It's caused by either low pressure over New Mexico or high pressure over Bermuda. Both are common in the summer. Both are rare in the winter. More than 80 percent of moisture that falls in the Midwest is from the Gulf of Mexico, and the primary cause of it coming here is the Bermuda high pressure. The pressure arrived very early and much stronger than usual by April and May this year. And it was the case in 1993."〔 〕 Taylor was quoted at length in the article, concluding: "Rule of thumb is, if a storm begins in the Texas panhandle, it will come to Iowa. The conditions that allow a storm to develop there are the conditions that move the storm to Iowa." The 2007-2008 winter was particularly severe in northeast Iowa, with a heavy snow cover that persisted in many areas until early spring rains. From the last week in April, the state experienced heavy rain, particularly in the form of thunderstorms, which saturated the soils. It was an extension of the Late-May 2008 tornado outbreak sequence, which aside from record-setting tornadoes, also brought huge quantities of rain in the form of stalled thunderstorm systems. Another possible, contributing factor was the extensive field tiling (installation of drain tile) in Iowa. Almost 40% of agricultural fields in Iowa are tiled, which allows water to flow more quickly from fields into waterways, possibly causing water levels to rise faster. Also, farming closer to creeks and rivers, without adequate buffer strips, allows the water to move rapidly from the field directly to the surface water. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Iowa flood of 2008」の詳細全文を読む スポンサード リンク
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