PROCEEDINGS ARTICLE | February 9, 2001
Proc. SPIE. 4169, Sensors, Systems, and Next-Generation Satellites IV
KEYWORDS: Polarization, Sensors, Calibration, Data storage, Satellites, Ultraviolet radiation, Clouds, Radiometry, Medium wave, Climatology
CLOUDS is a project co-funded by the EC under FP-4 (Environment and Climate), conducted by 12 European partners (7 scientific institutes and 5 industrial companies), also cooperating with NOAA/ETL. It is the mission study of a monitoring satellite to perform measurements necessary to describe cloud-radiation interaction in operational models for climate and long-term weather prediction. Complementary to missions for process study (Picasso-Cena, CloudSat, .. . ), CLOUDS addresses the monitoring aspect. As such, it has to comply with requirements of sufficiently frequent observing cycle, and operational sustainability. This prevents using active systems (radar and lidar) and leads to consider passive radiometry only, however exploiting as much as possible of the e.m. spectrum, with more polarisations and more viewing geometries. The paper reports on the instruments and system concepts developed to comply with the mission requirements. Six instruments are described, operating, respectively, in narrow channels of the UV/VIS/NIRISWIR, the TIRIFIR, the Sub-mm waves and the MW, in broad-band channels from UV to FIR, and in a relatively large-band channel of VIS/NIR. Several channels have three or four polarisations, all take images fore- and aft- (conical scanning), one has multi-angle-viewing capability. The overall system size is estimated as 900 kg mass, 1600 W power, 1 .1 Mbps data rate for real-time S-band transmission and 30 Mbps data rate for global data recovery in X-band.
