Global dimming
Global dimming refers to perceived widespread reduction of solar radiation received at the surface of the Earth from about the year 1961 to around 1990.
Definition courtesy of IPCC AR4.
All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.