Measurement of volcanic ash in Norwegian air space. WP 1.4.3 Improved estimates of ash cloud top temperature and surface temperature.

For retrieval of ash mass loading from infrared satellite measurements, estimates of the ash cloud temperature and the surface temperature are required. The ash cloud temperature and surface temperature may be taken from satellite measurements, weather model forecast, or deduced by satellite retrievals. The report describes various methods to estimate the ash cloud temperatue and surface temperature. The impact of varying cloud temperature and surface temperature on the signal measured by an IR-sensor in space is investigated.