Wildfires, Climate Change, and Human Health
Increasing global temperatures continue to give rise to adverse climate and weather outcomes. One such outcome is the increased prevalence and intensity of wildfires. While wildfires themselves are devastating, the smoke during and after wildfires are equally if not more dangerous to local residents, as well as those living far from the fire’s path. Wildfire smoke does not remain in one area, and its path is often unpredictable, which is one of the many reasons why these disasters affect an enormous population.
Air pollution is a daily threat to those with compromised immune systems and respiratory issues. The particulate matter in wildfire smoke has the potential to worsen negative health in those suffering from these conditions. As wildfire frequency increases, active measures will need to be taken to contain their damage and protect those most at risk from the smoke they leave behind.
In 2021, the National Interagency Fire Center recorded 58,985 wildfires and a total burn area of 7,125,643 acres in the United States. This is neither the highest number of wildfires ever recorded, nor the largest quantity of acreage burned, but this fact hides the reality that wildfire frequency, intensity, damage, and acute danger to human health have sharply increased in tandem with climate change. Just 18 wildfires caused at least $1 billion worth of damage each between 1980 and 2020, 15 of which took place after 2000.
The threats to personal safety, property, and livelihood are the easily seen outcomes of wildfire damage, but the more dangerous and insidious threat to human health is the particulate matter and gasses they produce.
Contained within wildfire smoke are hundreds of gaseous and particulate compounds that can be hazardous to human health. The chemical composition of these gasses depends heavily on the type of material that is burned in the fire. Some of these compounds are the same across most fires, such as carbon monoxide, carbon dioxide, and particulate matter (PM); however, other dangerous chemicals and compounds can make it into the smoke as well. A wildfire that burns through a tree farm will have very different components in its smoke than one that burns through a battery factory. Scientists have detected aldehydes, acid gases, sulfur dioxide, nitrogen oxides, polycyclic aromatic hydrocarbons (PAHs), benzene, toluene, styrene, metals, and more in wildfire smoke.
Climate change evidence suggests that wildfires will increase in intensity and frequency in the coming decades. According to NASA’s selected findings of the UN’s Intergovernmental Panel on Climate Change report, anticipated rising global temperatures will lead to a higher risk of forest fires and increased risk of deforestation. Higher temperatures can also increase the evaporation of water in the soil, resulting in forests that generally contain less water. These changes will make it difficult for forestry managers to implement plans that mitigate fire risk, including prescribed burns. These burns may additionally produce more dangerous PM, further increasing future risk.
The trouble with wildfire smoke is that it does not stay in one place or affect just one population like other environmental health factors might. As a result, the rise in annual fire risk affects individuals who live beyond the immediate fire danger via the spread of smoke carried to them from the epicenter of the blaze. Mitigating the root causes of climate change, especially drought, can help reduce the impact that these wildfires and their smoke could have on human health.
