Large wildfires make headlines that spread across the world. This certainly does nothing to lessen the negative stigma attached to them.
That is why it was so interesting to come across a study examining the impact of wildfires in the western United States on air quality in other parts of the country. The researchers’ hypothesis was that wildfires would worsen air quality simply because of smoke transport.
However, the hypothesis turned out to be incorrect. Ma and colleagues showed that extreme wildfires in the West actually reduce fine particle concentrations in the eastern United States by roughly the same amount as they increase them in the West.
This surprising result was explained by the fact that heat-induced convection from the fires weakens eastward transport of smoke and enhances the removal of air pollutants through precipitation. In fact, this mechanism reduces human mortality and economic losses nationwide!
Of course, it is welcome news that the health effects of wildfires may not be as dramatic as feared. Yet in my view, the real lesson of this study lies elsewhere. It once again demonstrates that ordinary and seemingly logical assumptions people make do not necessarily correspond to reality. At the same time, it helps to highlight why systematic science is very likely one of humanity’s most important institutions.
Previous thoughts on the same topic:
Control of Douglas fir beetles by woodborer beetles
Forests in Indonesia and Finland
Scientific misconduct on prevailing theories is too attractive
