American Heritage Dictionary
(5)
Century Dictionary
(5)
GNU Webster's 1913
(3)
WordNet
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Elsewhere on the web
Gerlich & Tscheuschner claim and support their claims that the IPCC modeling approach assumes an invalid physical model for the insolation and radiation of heat from the Earth and an invalid physical model for radiation among gas molecules.— RealClimate
Further, it goes without saying that the radiation balance, i.e., insolation (solar irradiation), energy absorption and back radiation by the Earth, plays a crucial role and cannot be omitted, which means that even the Earth itself is not a closed system. classical mechanics, that predicts the characteristics of the climate and of which the truth is accepted by all climatologists.— Citizendium, the Citizens' Compendium - Recent changes [en]
Reliable data for site-specific solar radiation (insolation) is critical to estimating solar capabilities.— The Oil Drum - Discussions about Energy and Our Future
Fortunately, a massive database for insolation is posted on the National Renewable Energy Laboratory (NREL) website.— The Oil Drum - Discussions about Energy and Our Future

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