A study led by scientists at the University of Washington claims ship emissions bring more intense lightning and thunderstorms above the world’s busiest tradelanes.
The results of the analysis were published this week in the journal Geophysical Research Letters.
The study mapping lightning around the globe found 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.
Aerosol particles emitted in the exhaust of ships are changing how storm clouds form over the ocean, the scientists claim. The particles from ship exhaust make cloud droplets smaller, lifting them higher in the atmosphere which in turn creates more ice particles and ultimately more lightning.
“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 lead author Joel Thornton, a professor of atmospheric sciences at the University of Washington.
Of 1.5bn lightening strikes analysed across the globe from 2005 to 2016 the team found nearly twice as many lightning strokes on average over major tradelanes in the northern Indian Ocean, through the Strait of Malacca, and into the South China Sea, compared to adjacent areas of the ocean that have similar climates.