GROUND SIGNATURE OF AN ANTECEDENT PRECIPITATION EVENT: DETECTION OF SURFACE COOLING BY AVHRR SATELLITE DATA

Abstract

Evaluation of the Advanced Very High Resolution Radiometer (AVHRR) sensor on-board the National Oceanic and Atmospheric Administration (NOAA) satellites shows that the spatial pattern of rainfall distribution can be detected on data acquired after a precipitation event. The thermal infrared spectral region of AVHRR data shows good comparison to rainfall amount and distribution recorded at NOAA cooperative weather service rain gauges. The thermal infrared information indicates a cooling of temperature associated with measured rainfall. Latent energy of evaporation, soil thermal properties, and transpiration contribute to the observed cooling. After surface drying following a rainfall event, thermal inertia and evapotranspiration remain sufficiently affected so that the increased soil moisture is detected through decreases in temperature, independent of land cover and soil type.