title: Do satellites detect trends in surface solar radiation?
abstract: Long-term variations in solar radiation at Earth's surface (S) can affect our climate, the hydrological cycle, plant photosynthesis, and solar power. Sustained decreases in S have been widely reported from about the year 1960 to 1990. Here we present an estimate of global temporal variations in S by using the longest available satellite record. We observed an overall increase in S from 1983 to 2001 at a rate of 0.16 watts per square meter (0.10%) per year; this change is a combination of a decrease until about 1990, followed by a sustained increase. The global-scale findings are consistent with recent independent satellite observations but differ in sign and magnitude from previously reported ground observations. Unlike ground stations, satellites can uniformly sample the entire globe.
authors.affiliation: Department of Meteorology, University of Maryland, College Park, MD 20742, USA.
authors.forename: R T
authors.initials: RT
authors.lastname: Pinker
authors.forename: B
authors.initials: B
authors.lastname: Zhang
authors.forename: E G
authors.initials: EG
authors.lastname: Dutton