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2.0 Protecting Life and Property through Improved Weather Prediction


Scientific understanding of the atmosphere and the ability to forecast the large-scale evolution of the weather have increased dramatically over the past two decades. Today, general forecasts of temperature and precipitation are as accurate at 48 hours as they were at 24 hours a generation ago. Significant skill exists today in six-day forecasts, where little existed ten years ago. This progress has been possible because of the major investments made by the nations of the world in support of meteorological operations and research. These investments have improved global observations, primarily by weather satellites, and have provided supercomputers to process the data and run sophisticated forecast models of the global atmosphere. However, these technological advances by themselves would have been fruitless without the better scientific understanding that has resulted from sustained international operational and research programs.

Much of the progress was initiated by two highly successful international programs that grew out of a speech by President Kennedy to the United Nations in 1961. The World Meteorological Organization (WMO) of the United Nations developed the World Weather Watch, which coordinates the collection and exchange of meteorological data from all nations. These data were used in a complementary research effort, the Global Atmospheric Research Program, to improve our understanding and ability to predict day-to-day changes in large-scale weather patterns. The research involved a series of focused international field experiments coordinated by the intergovernmental agency WMO and the nongovernmental scientific agency the International Council of Scientific Unions (ICSU).

In spite of the resulting improvements in forecasts of large-scale weather patterns beyond one day, the weather events that are usually most significant for society--smaller-scale, rapidly developing events such as flash floods, thunderstorms, hail, tornadoes, wind shear, hurricanes, and heavy snow--are neither understood, observed, nor predicted as well as they could be.

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