Earth Surface Infrared Ultraspectral Emissivity Images Derived From Space Borne Measurements for Environmental Monitoring

Surface emissivity and skin temperature derived from the current and future operational satellites can and will reveal critical information on the Earth?s ecosystem and land surface type properties. Satellite ultraspectral data have been shown to be significant to atmospheric research and monitoring the Earth?s environment. The Earth Observing System (EOS) Aqua satellite with the Atmospheric InfraRed Sounder (AIRS) on board was launched on 4 May 2002. The Infrared Atmospheric Sounding Interferometer (IASI), on the Metop-A satellite, launched on 19 October 2006, is the first of the advanced ultraspectral resolution temperature, humidity, and trace gas sounding instruments for the purpose of improved weather, climate, and air quality observation and forecasting. Future satellite systems, such as the IASI on the European Metop-B and -C satellites and the Cross-track Infrared Sounder (CrIS) on the NPOESS Preparatory Project and the continuing JPSS series of satellites, will continue to provide ultraspectral IR radiance observations that will be used for long-term monitoring for the Earth?s environment and global climate change. Long-term and large-scale observations needed for global change monitoring and other research can only be supplied by satellite based remote sensing. Surface emissivity retrieved from satellite ultraspectral IR measurements can be greatly beneficial but not limit to the assimilation of ultraspectral resolution IR radiances in numerical weather prediction models, climate simulation, and the surface temperature retrieval from other satellite broad-band measurements. In this paper, a retrieval algorithm is briefly described with samples demonstrating surface emissivity spectra retrieved from different surface types. Global surface emissivity with a spatial resolution of 0.5?0.5 degrees of latitude-longitude are produced with temporal variation to indicate seasonal diversity of global land surface emissivity. We demonstrate the ultraspectral IR emissivity images retrievable with IASI satellite global measurements in conjunction with some initial retrieval analyses. IASI is a Michelson interferometer with spectral coverage between 3.6 and 15.5 ?m. At nadir, the instrument samples data at intervals of 25 km along and a cross track, each sample having a maximum diameter of about 12 km. We are also able to demonstrate that surface emissivity images from satellite measurements can be used in assistance of monitoring global change.