World Wide Lightning Location Network's 2005 to 2016 lightning strikes records have some interesting pattern that caught Joel Thornton at the University of Washington in Seattle and colleagues' attention.
When looked closely, more strikes apparently occur in specific regions of the east Indian Ocean and the South China Sea, than the adjacent area. What's weird is that they usually take place along two straight lines in the open ocean. And what's in there? Two of the busiest shipping lanes in the world.
“We were quite sure the ships had to be involved,” says Thornton. So, they ruled out other factors that can affect storm intensity, like wind speeds and temperatures. With this, they found that the soot ships' spews into the pristine ocean air were the culprit.
Aerosol particles from the ships’ engine exhausts seed the water vapour that consequently form into cloud droplet. This means that the more cargo ships, the more small, light cloud drops. These then turns into icy clouds as their lightness enables them to rise up high into the atmosphere and freeze. Clean air has lesser seeds and produces heavier cloud drops that quickly falls as rain.
"It is this that leads to more intense thunderstorms: lightning only occurs if clouds are electrically charged, and this only happens if there are lots of ice crystals," Newscientist reported.
“Understanding this anthropogenic effect can help us predict future climate,” says Orit Altaratz Stollar of the Weizmann Institute of Science in Israel.
This shows the great effect of human activities on the changes in Earth's atmosphere. Thornton also suggest that we may have released enough pollution before to actually affect greatly the storms and lightning in many places we're not even conscious of.
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