Scientific requirements for a Moderate-Resolution Imaging Spectrometer (MODIS) for EOS

The MODIS is an instrument planned for the sun-synchronous polar orbiting segment of the Space Station system. The radiometer is required to have 1 km resolution in terrestrial remote sensing applications. The monitoring program is targeted to last 10 yr in order to provide a sufficient database for discerning trends as opposed to natural variations. The study areas of interest include tropical deforestation, regrowth and areal distributions, acid rain effects on northern forests, desertification rates and locations, snow cover/albedo relationships and total biomass. MODIS will have 192 channels with 30 m spatial resolution and cover seven bands in the 3.5-12 microns interval for land viewing. Ocean studies will be carried out in 17 bands from 0.4-1.0 micron, and atmospheric scans will be performed over the land and ocean intervals at narrowband wavelengths (1.2 nm). Si detector arrays will be used and will be accompanied by an expected 600:1 SNR and produce data at a rate of 1.4-9.1 Mb/sec.