This also means the ideas of adding volcanic dust into the air would work for cooling the climate if necessary.
Researchers have calculated how much of the Atlantic Oceans warming observed during the last 26 years can be accounted for by concurrent changes in African dust storms and tropical volcanic activity, primarily the eruptions of El Chichïan in Mexico in 1982 and Mount Pinatubo in the Philippines in 1991.
In fact, it is a surprisingly large amount, Evan says. "A lot of this upward trend in the long-term pattern can be explained just by dust storms and volcanoes," he says. "About 70 percent of it is just being forced by the combination of dust and volcanoes, and about a quarter of it is just from the dust storms themselves."
The result suggests that only about 30 percent of the observed Atlantic temperature increases are due to other factors, such as a warming climate. While not discounting the importance of global warming, Evan says this adjustment brings the estimate of global warming impact on Atlantic more into line with the smaller degree of ocean warming seen elsewhere, such as the Pacific.
"This makes sense, because we don't really expect global warming to make the ocean [temperature] increase that fast," he says.