Less Pollution Creates More Hurricanes: Tropical Storms Increase with Fewer Aerosols

Less pollution is always a good thing, right? Cleaner air means fewer problems with health and our planet. Yet scientists have now found an interesting and disturbing side effect of a cleaner atmosphere. Efforts to reduce air pollution could result in more hurricanes.

Aerosols are a significant portion of air pollution. Throughout most of the 20^th century, humans have released greenhouse gases and other waste into the air, including aerosols. These aerosols in particular formed urban smog, darkened buildings and caused acid rain. Yet as countries enacted clean air legislation, these pollutants were reduced. This led researchers to wonder exactly how these particles may have affected our climate.

Using climate simulations, the researchers matched storm records and predictions from 1860 to 2050 with recorded and predicted levels of atmospheric pollution. After examining these simulations, they were able to identify an effect, according to The Guardian.

Surprisingly, these pollutants may actually help suppress tropical storms. The airborne particles can reduce the strength of storms by "seeding" clouds and encouraging rain. Aerosols also prevent hurricanes by reducing North Atlantic surface temperatures, according to the Australian. In fact, the researchers found that tropical storms were far less frequent during periods when aerosols were more highly concentrated in the atmosphere.

"External factors, particularly anthropogenic aerosols, could be the dominant cause of historical tropical storm variability," reported the researchers in the study. In fact, it turns out that sharp declines in aerosols allowed the frequency of tropical storms to increase.

The research isn't the first of its kind, either. There are several studies that seem to suggest the same effect. Smog and other discharges in the northern hemisphere in the mid-20^th century were recently linked to the drying out of the Sahel and much of Lake Chad, according to The Guardian. This means that aerosols have a huge impact on our climate.

That doesn't mean we should continue to release aerosols to reduce tropical storms. The fact that this phenomenon can cause drought in other locations, such as with the Lake Chad study, shows the importance of regulating this pollution. It also reveals how much of an impact we have on our planet, and could help create future climate models.

The findings are published in the journal Nature Geoscience.