Science

Different radar designs produce instruments that are directly sensitive to a very broad range of geophysical variables, and which can therefore be used to monitor and improve our scientific understanding of many different physical phenomena, including:

• The year-to-year variability of sea ice in polar regions
• Earth's rapidly changing glaciers and ice sheets
• The 3-dimensional structure of forests and, more generally, above-ground biomass in different environments
• The large-scale movement of ocean water masses, as well as the changes in river and lake water levels globally
• The vertical fluxes of rain and snow in the atmosphere, and the associated latent heating or cooling
• High-resolution topographic mapping, and the geophysical deformations underlying catastrophic events such as earthquakes, volcanic eruptions and sudden (as well as slow) subsidence events
• The measurement of wind vector fields over the oceans
• The search for liquid water and ice under planetary surfaces
• The radiometric properties of terrestrial and extraterrestrial materials.

This explains the breadth of the scientific research and application efforts in Section 334, which include using data from air- and spaceborne radars and other instruments to characterize, understand, and try to improve the predictability of this diverse range of atmospheric, surface and solid Earth phenomena, as well as analyzing, designing, implementing, testing and validating radar processing algorithms for different kinds of synthetic aperture radars, interferometers, scatterometers, sounders, and atmospheric radars.

The two images show exactly the same area in South America – the Guiana Highlands straddling the borders of Venezuela, Guyana and Brazil. The panel on the left was created using the best global topographic data set available in 1999, the US Geological Survey's GTOPO30.The panel on the right was generated with the new data set created by the Shuttle Radar Topography Mission (SRTM) called SRTM30, which represents a significant improvement in our knowledge of the topography of much of the world. GTOPO30, with a resolution of about 900 meters, was compiled over a three-year period from a number of different map sources, with very inconsistent quality. The SRTM data were collected within a ten-day period using the same synthetic aperture radar, and have an intrinsic resolution of about 30 meters.