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the U.S. Agency for International Development requested the EROS Data Center of the U.S. Geological Survey in Sioux Falls, S. Dak., to develop and put into place a seasonal vegetation monitoring program. The program uses National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer (AVHRR) satellite data and USGS geographic information systems technology.
The greenness field sheets
provide information on
favorable grasshopper and
Data received daily from the AVHRR were merged with a cartographic data base to produce Normalized Difference Vegetation Index (greenness) field sheets. The field sheets are produced at a scale of 1:2,500,000 (1 inch
represents about 40 miles) for most countries and are sent by express mail from South Dakota to Africa every 2 weeks. The greenness information, which relates to vegetation growth and condition, is used to monitor the complex seasonal patterns of greening-up and drying of vegetation on a countrywide basis through the critical periods of vegetation growth and grasshopper and locust activity.
The field sheets are used by numerous organizations involved in grasshopper and locust control in Africa. The primary users include national crop protection services in Africa, the U.S. Agency for International Development, and the United Nations Food and Agriculture Organization. Training is provided to users in each country on how to interpret and to use the information in their surveillance systems. Grasshopper and locust control teams use the sheets for planning and conducting field and aerial surveys to locate infestation areas more efficiently. Sheet use is based on the principle that seasonal rainfall triggers both the growth of herbaceous vege
Lessons from the
By Walter W. Hays
Armenia, a Soviet Socialist Republic, is located in an environment where, over time, the collision of the Eurasian and Arabian tectonic plates has produced a broad zone of faulting and crustal deformation that extends southward from the Caucasus Mountains in Armenia to northern Turkey and Iran. The December 7, 1988, earthquake that centered on Spitak, Armenia, is the latest in a long series of earthquakes in the region that reflects the ongoing collision of the plates. The magnitude 6.8 earthquake was one of the worst disasters of the 20th century. It struck Spitak at 11:41 a.m., local time, and left an estimated 25,000 dead, 18,000 injured, 510,000 homeless, and reconstruction costs of $16 billion. It reminded the world of the damage that an earthquake can do to a nation, its urban centers, gross national product, and to the fabric of the society.
An earthquake disaster can serve as an ail-too uncomfortable reminder of how unprepared an area may be to cope with such a calamity. Such disasters show whether or not preparedness planning and mitigation measures were adequate. They also test the siting, design, and construction practices for lifelines, buildings, and critical facilities. Perhaps most critically, earthquakes and their aftermath stretch the capacity of the populace to respond to these disasters and to modify their activities and practices during the recovery period.
Multidisciplinary studies of the 1988 Armenia earthquake by a U.S. team of experts in cooperation with their Soviet counterparts and previous studies of