Regional Evolution of the Meteosat Solar and Infrared Spectra (2005-2024) Linked to Cloud Cover and Ocean Surface

We analyze the evolution of a few atmospheric and surface physical properties on Earth over a period of 20 years (period from 2005 to 2024) through the radiance fluxes measured by the Meteosat Second Generation (MSG) satellites. The results show significant changes in time in the solar (–1.3 %) and infrared domains (+0.4%), consistent with data from similar radiometers on other satellite platforms. We conclude that the outgoing solar radiation flux (OSR) decreases as a result mainly of low-level cloud reduction under the nominal Meteosat field of view (MFoV) at 0-degrees longitude in the geostationary orbit. We relate regional changes in 60 subareas to the cloud distribution high and low in the atmosphere, and show the connection between the imbalance at the top of the atmosphere and the observed variation in sea surface temperature (SST) in the Atlantic. We also discard a significant cirrus variation in the 20 years of the study, in spite of aviation forcing at high levels.