Broadband solar radiances from visible band measurements: a method based on ScaRaB observations and model simulations
Abstract:Using simultaneous and co‐located broadband and narrowband observations of solar radiation from the Scanner for Radiation Budget (ScaRaB) instrument on Meteor‐3 during 1994–1995, empirical relationships between ScaRaB visible band and broadband solar radiances are derived for different surface types, cloud amounts, solar zenith angles and satellite viewing angles. Relationships between ScaRaB visible channel and National Ocean and Atmosphere Administration (NOAA) Advance Very High Resolution Radiometer (AVHRR) visible channel radiances are derived from radiation transfer model simulations for different surface types and cloud cover. Combining the narrow‐to‐broadband (NTB) and narrowband‐to‐narrowband (NTN) relationships, broadband solar radiance can be derived from narrowband radiances measured by the AVHRR on operational meteorological satellites. The derived NTB conversion coefficients are evaluated against independent data. Radiances are converted to fluxes by the application of angular distribution models. Typical differences between fluxes derived from ScaRaB narrowband and broadband channels are of the order of 1 W m −2 with standard deviations of the order 15 W m −2 .
Document Type: Research Article
Affiliations: Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, Quebec, H3A 2K6, Canada
Publication date: November 20, 2005