Ship exhaust makes oceanic thunderstorms more intense

Lightning near an aircraft carrier in the Strait of Malacca.

Thunderstorms directly above two of the world’s busiest shipping lanes are significantly more powerful than storms in areas of the ocean where ships don’t travel, according to new research.

A new study mapping lightning around the globe finds lightning strokes occur nearly twice as often directly above heavily-trafficked shipping lanes in the Indian Ocean and the South China Sea than they do in areas of the ocean adjacent to shipping lanes that have similar climates.

The difference in lightning activity can’t be explained by changes in the weather, according to the study’s authors, who conclude that aerosol particles emitted in ship exhaust are changing how storm clouds form over the ocean.

“It’s one of the clearest examples of how humans are actually changing the intensity of storm processes on Earth through the emission of particulates from combustion,” said Joel Thornton, an atmospheric scientist at the University of Washington in Seattle and lead author of the new study in Geophysical Research Letters, a journal of the American Geophysical Union.

Read more at American Geophysical Union »