Continuing high spatial resolution data from the Landsat and SPOT satellites, passive microwave data from the Special Sensor/Microwave Imager (SS/MI) and continuing meteorological satellite coverage from the NOAA, GOES, GMS and Meteosat series all mean that the remotely sensed techniques described in this chapter can continue to be employed and expanded upon.
New sensors, particularly in the microwave region, promise great potential for hydrologic applications [ Blyth, 1993]. There are several satellites, such as ERS-1, the JERS-1, and Radarsat to be launched by the Canadians that will provide useful data to hydrologists. All carry single-polarization, single-wavelength, synthetic aperture radars, plus radiometers at various wavelengths. An additional satellite being planned is the Tropical Rainfall Measurement Mission (TRMM) [ Simpson et al., 1988].
The EOS (Earth Observational System) [ Butler et al. 1988], and its counterpart European and Japanese platforms, will lead to considerable advances in the understanding of all the earth sciences, including hydrology. EOS includes the organization and archiving of the data in an information system where time series of all the data will be readily available.
There are many new and exciting observations of the hydrologic cycle that are going to be available from new satellite systems, and concurrently, new models to allow the data to be analyzed and address previously intractable problems. Remote sensing can provide many of the necessary data to supplement conventional data to expand hydrology in new directions and also provide entirely new data types and forms that will help hydrologists tackle previously unsolvable questions.