The ultra-fine particulates emitted by modern coal-fired power stations are wreaking havoc on global rainfall patterns, a new 15-year international study has found.
The study has found that filtration systems on modern coal-fired power stations are the biggest source of ultra-fine particulates and have considerable impacts on climate in a number of ways.
In the Bulletin of the American Meteorological Society, the researchers report how coal-fired power stations clearly emit large amounts of ultrafine particles (UFP) through filtering technology of exhaust gas.
The key findings of the long-term study are:
Modern coal-fired power stations emit more UFP than urban road traffic
UFP can harm human health
UFP can affect rainfall distribution on local to regional scales by increasing the condensation nuclei count
UFP can be transported in layers with high concentrations for hundreds of kilometres and then lead to localised “particle events” (dramatic spikes in short-term particle concentrations on the ground) far away from their source.
“Our two research aircraft are particularly suitable to follow the plumes from the smoke stacks downwind for hundreds of kilometres and study their behaviour in great detail,” says Professor Hacker, who is based at Airborne Research Australia (ARA) in South Australia.
The scientists then linked these data with meteorological observations and used dispersion and transport models to trace back their origin.
“In this way, we found that fossil power stations have for many years become the strongest individual sources of ultrafine particles worldwide. They massively influence meteorological processes and may cause extreme weather events, including intensive rain events.
“By redistributing rainfall events, this can lead to drier than usual conditions in some places and to unusually heavy and persistent strong rainfall elsewhere,” Professor Hacker says.