Where's Waldo ... and 6 billion others?Scientists at Oak Ridge Oak Ridge, city (1990 pop. 27,310), Anderson and Roane counties, E Tenn., on Black Oak Ridge and the Clinch River; founded by the U.S. government 1942, inc. as an independent city 1959. (Tenn.) National Laboratory have combined satellite imagery Satellite imagery consists of photographs of Earth or other planets made from artificial satellites. History The first satellite photographs of Earth were made August 14, 1959 by the US satellite Explorer 6. and detailed census data to develop a worldwide database that can provide estimates of the number of people located in areas on a grid that has boxes with areas of 1 square kilometer or less. The researchers describe the LandScan database, which they say will help determine populations at risk from natural and manmade disasters, in the July PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING Deriving digital models of an area on the earth. Using special cameras from airplanes or satellites, either the sun's reflections or the earth's temperature is turned into digital maps of the area. . Jerome E. Dobson dob·son n. See hellgrammite. [Probably from the name Dobson.] Noun 1. dobson - large brown aquatic larva of the dobsonfly; used as fishing bait hellgrammiate and his colleagues used satellite images and other geographic data Geographic data is about much more than electronic pictures of maps. The geographic data that describes our world allows for city planning, flood prediction and relief, emergency service routing, environmental assessments, wind pattern monitoring and many other applications. to determine land characteristics, such as the slope of terrain, and the prevalence of roads and nighttime lights. With this information, scientists can estimate the number of people located in rectangles measuring 30 arcseconds of the Earth's circumference on a side. Such cells measure 1 km on a side at the equator and become smaller as latitudes increase. Although future versions will provide both a daytime and a nighttime allocation of people, the new database gives a single estimate. For example, the calculations assume that the traffic on roads stretching through unpopulated deserts will place small numbers of people in the area during the day. "This database has a higher resolution and is more realistic than any that's been produced to date," says Andrew T. Bower, a geospatial Geospatial is a term widely used to describe the combination of spatial software and analytical methods with terrestrial or geographic datasets. The term is often used in conjunction with geographic information systems and geomatics. analyst at the National Imagery and Mapping Agency in Washington, D.C. The researchers are currently working on next year's model. "We recently received a ton of data--literally," Dobson says. The two pallets of CD-ROMs, which weighed a total of 2,086 pounds, contained geographical information that's far more detailed than what's included in the current model. Dobson predicts that government agencies will use the high-resolution population plots to estimate numbers of people at risk from volcanic eruptions volcanic eruptions discharging of fumes, dust and lava from volcanoes. They have damaging potential in addition to those of being physically overpowering by the lava flow or the ash or dust fallout. , floods, and other large disasters, as well as from more localized threats, such as releases of toxic chemicals Any chemical which, through its chemical action on life processes, can cause death, temporary incapacitation, or permanent harm to humans or animals. This includes all such chemicals, regardless of their origin or of their method of production, and regardless of whether they are produced . Personnel at the State Department have already taken advantage of the LandScan model--when they planned the U.S. response to the flooding in Mozambique last March. "The better an idea we have of where people are and how they can be reached, the better they can be helped," says William B. Wood, director of the State Department's Office of the Geographer and Global Issues. |
|
||||||||||||||||||
Printer friendly
Cite/link
Email
Feedback
Reader Opinion