The river's rising: a depressing effect.When the rivers in the Amazon basin flood their banks each rainy season, the added weight of the water causes land throughout the region to sink, scientists say. At Manaus, Brazil, the land rises and falls Rise and Fall redirects here. For the Belgian hardcore band, click here. Rises and falls is a category of the ballroom dance technique that refers to rises and falls of the body of a dancer achieved through actions of knees and feet (ankles). as much as 75 millimeters each year, more than has been measured anywhere else on Earth, says geophysicist Michael Bevis of Ohio State University Ohio State University, main campus at Columbus; land-grant and state supported; coeducational; chartered 1870, opened 1873 as Ohio Agricultural and Mechanical College, renamed 1878. There are also campuses at Lima, Mansfield, Marion, and Newark. in Columbus. However, the variation doesn't appear to be correlated with rainfall in Manaus itself, so soil swelling probably isn't causing the elevation change. The fluctuation is in perfect sync with the 15-meter annual rise and fall of the nearby Rio Negro, a major tributary of the Amazon, Bevis and his colleagues report in the Aug. 28 Geophysical Research Letters Geophysical Research Letters is a publication of the American Geophysical Union. GRL is the organization's only letters journal. Since its introduction in 1974, GRL has published only short research letters, typically 3-5 pages long, which focus on a specific discipline or . When the Rio Negro rises and floods, Earth's crust in the region sinks, they note. Bevis and his colleagues accidentally discovered the synchrony synchrony /syn·chro·ny/ (-krah-ne) the occurrence of two events simultaneously or with a fixed time interval between them. atrioventricular (AV) synchrony in land and water motions while examining Global Positioning System Global Positioning System: see navigation satellite. Global Positioning System (GPS) Precise satellite-based navigation and location system originally developed for U.S. military use. (GPS) data collected from 1997 to 2002. Although GPS data have previously revealed changes in elevation near lakes and reservoirs as their water levels rise and fall, the data gathered in Manaus are the first to show such land-elevation oscillations caused by a body of flowing water.--S.P. |
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