3-D computer simulations may stimulate weather forecasting

Meteorologists are swamped with information. Weather satellites, radars, and other instruments can produce hundreds of thousands of data points describing an atmospheric scene. Both weather research and forecasting would gain if this data were presented so that key points could be grasped quickly. One way to do this is to use computer processing to present the information as three-dimensional images projected onto a two-dimensional surface such as a computer screen or a sheet of paper.

Arthur F. Hasler of the National Aeronautics and Space Administration's Goddard Space Flight Center and his colleagues explain in the July issue of the Bulletin of the American Meteorological Society that ``computer-synthesized representations can now be made of nearly any real-life object.'' These include such meteorological ``objects'' as storms and cloud systems.

For example, satellite pictures taken by infrared (heat) radiation give cloud height data. Pictures taken in visible light give information on shadowing and shading. These two kinds of data can be combined to yield realistic 3-D images of, say, a hurricane. If the visible light data are missing, as they are for night scenes, a computer program can supply substitute shading.

Combining a series of such images produces a movie strip which, the scientists say, ``creates the impression of actually flying down into a hurricane.''

Nonvisual data can also be combined into a simulated 3-D image, as in the picture shown here. It was synthesized from satellite and aircraft data of a cloud system that produced water spouts. As display techniques improve, Hasler says, they should, among other uses, add a dramatic new aspect to the TV weather reports.