Kalman filter physical retrieval of surface emissivity and temperature from geostationary infrared radiances

[摘要] The high temporal resolution of data acquisition by geostationary satellitesand their capability to resolve the diurnal cycle allows for the retrieval of a valuable source ofinformation about geophysical parameters. In this paper, we implementa Kalman filter approach to apply temporal constraints on the retrievalof surface emissivity and temperature from radiance measurements made fromgeostationary platforms. Although we consider a case study in which we apply astrictly temporal constraint alone, the methodology will be presented in itsgeneral four-dimensional, i.e., space-time, setting. The case study we consideris the retrieval of emissivity and surface temperature from SEVIRI (SpinningEnhanced Visible and Infrared Imager) observations over a target areaencompassing the Iberian Peninsula and northwestern Africa. The retrievalsare then compared with in situ data and other similar satellite products.Our findings show that the Kalman filter strategy can simultaneouslyretrieve surface emissivity and temperature with an accuracy of ± 0.005and ± 0.2 K, respectively.

[学科分类] 几何与拓扑