Cleaner ship fuel is reducing lightning in key shipping lanes, KU research shows:
Cuts in sulfur emissions from oceangoing vessels have been tied to a reduction in lightning stroke density along heavily trafficked shipping routes in the Bay of Bengal and the South China Sea, according to new research from the University of Kansas.
Previous studies had found frequent lightning along shipping routes over the Bay of Bengal before a 2020 International Maritime Organization rule capped sulfur in fuel used by oceangoing ships, leading to a roughly 70% drop in sulfate emissions in the Bay of Bengal.
"I think there are two reasons for this," said lead author Qinjian Jin, assistant teaching professor of geography & atmospheric science at KU. "The first is the shipping activity is so frequent that it releases a lot of sulfate aerosols, more than other oceanic regions. The second is that the Bay of Bengal is an area where we see lots of strong convection that is required for lightning to occur. I think both reasons contribute to the observed frequent lightning activity over this region."
Jin said these two ocean regions best revealed the connection between shipping emissions and lightning. The KU researcher and his colleagues found lightning-stroke density — the number of individual lightning discharges, or "strokes," per square kilometer — to be about 36% lower than before the 2020 IMO sulfur cap.
"The drop in sulfates from ships can cause fewer cloud condensation nuclei, larger cloud drops, weaker convection and storms, and thus fewer ice crystals and less frequent lightning," Jin said.
[...] "When we have more sulfate aerosols, or more cloud nuclei, the cloud droplets become smaller," he said. "When they're smaller, it's harder for precipitation to occur. Clouds can last longer in the atmosphere. With a longer lifetime, they have a higher chance to develop into high clouds, where ice clouds form. When we have more ice clouds, we have a higher chance of lightning. That is how sulfate aerosols can be connected to lightning."
While the 2020 regulations on shipping were intended to clean up the air, the reduction in lightning can be seen as a side benefit as it can be dangerous to mariners and equipment as well as hinder visibility and normal operations at sea. Jin said another consequence of the shipping regulation might be warmer global temperatures.
"Due to the 2020 emission regulation imposed by the International Maritime Organization, we observed a decrease in sulfur emissions from ships after 2020," he said. "With less sulfate aerosol emitted from ships, we observed darker clouds over the North Atlantic Ocean and the Pacific Ocean. Because clouds become darker, they absorb more solar radiation. Our previous studies imply that the decrease in shipping sulfate aerosols could be responsible for the record-breaking global warming temperatures in 2023 and 2024."
Journal Reference: Jin, Q., Huang, J., Wei, J. et al. Observational evidence of reduced Bay of Bengal lightning since 2020 linked to cloud responses to shipping emission regulations. npj Clim Atmos Sci 8, 350 (2025). https://doi.org/10.1038/s41612-025-01256-w
(Score: 3, Informative) by JoeMerchant on Tuesday March 03, @01:34AM (8 children)
Lakeland, Florida - home of Phosphate strip mines producing 25% of the global supply of phosphates, and the chemical processing plants that refine the ore.
Heat and humidity are part of the equation, but cloud seeding is a real thing.
When they used to have coal fired power plants on the Florida coast, you could see the yellow stripe (sulphur) leaving the stacks and streaking across the sky for tens of miles.
🌻🌻🌻🌻 [google.com]
(Score: 4, Informative) by pTamok on Tuesday March 03, @06:43AM (7 children)
As someone who writes mostly "Commonwealth English", the correct spelling is "sulfur". IUPAC have opined [nature.com].
The yellow colour was probably not elemental sulfur in an industrial combustion process exhaust, as I would expect the sulphur to have been oxidized to sulfur dioxide, which is colourless. It was more likely diluted nitrogen dioxide which in its pure form is a very deep dark reddish-brown.
A non-industrial exhaust could well contain unburned fuel which could colour the exhaust gases, and the colour could easily come from volatalized unburned organic chemicals from coal or wood, for example.
(Score: 4, Funny) by PiMuNu on Tuesday March 03, @09:31AM (5 children)
> the correct spelling is "sulfur"
Stop eroding my culture.
Next you will insist that aluminium is wrong. And miles.
(Score: 2) by janrinok on Tuesday March 03, @10:20AM (2 children)
I agree: Sulphur and aluminium. !
[nostyle RIP 06 May 2025]
(Score: 1) by pTamok on Tuesday March 03, @05:03PM (1 child)
'fraid not. IUPAC mandate 'sulfur', but give 'aluminum' as an acceptable variant to 'aluminium', although aluminium is preferred. Similarly, people who spell 'caesium' as 'cesium' are allowed to get away with it.
(Score: 2) by aafcac on Tuesday March 03, @10:48PM
It was aluminum before it was aluminium which mostly became a thing because of other metals like titanium and magnesium. But, honestly making it aluminium it just adds a syllable.
(Score: 2) by Freeman on Tuesday March 03, @03:04PM (1 child)
Wait, wouldn't you be using kilometers? I am now very confused. Are sure your culture isn't already amalgamated?
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 2) by PiMuNu on Tuesday March 03, @03:57PM
No! kilometers [sic] are an outcome of French dictatorship. Down with the papists.
(Score: 2) by JoeMerchant on Tuesday March 03, @01:51PM
I bet you're right about the color - however, the sulphur (North American variety) is still there. Florida has enough seabreezes to disperse it out over the Gulf of Mexico and Atlantic Ocean, and when the wind blows that way the plant operators would turn off the (EXPENSIVE!) stack scrubbers, leading to the highly visible streak leaving the stacks off into the sunset / sunrise. In the more industrialized Northeast, the coal combustion exhaust would come back down in the rain (infamous acid rain) increasing (North American) sulphuric acid content of lakes and streams sufficiently high to kill the fish. It's harder to kill a fish with acid rain than to gas a canary in a coalmine, and the message is the same: keep going and this will be you.
🌻🌻🌻🌻 [google.com]