Wildfire smoke-related deaths could double by 2100
Monday, September 24, 2018, 16:36 - Despite a continuous decrease in the concentration of fine particulate matter from U.S. anthropogenic sources, a new study reveals that the concentration of the same type of particles coming from wildfires is rising, and will continue to do so during the next century. This would offset the tremendous improvements gained over the past decade by continued reductions in anthropogenic emissions, therefore leading to worse air quality, degraded visibility and increases in population exposure across wide regions of the country.
A group of atmospheric researchers led by Dr. J.R. Pierce from the Department of Atmospheric Sciences at Colorado State University, have been using Global Climate Model simulations (GCMs) to estimate the impacts of changing fire emissions on air quality, visibility, and premature deaths in the middle of the 21st century.
California wildfire. Courtesy: NOAA.
On a positive note, the study shows that fine particulate matter coming from anthropogenic sources will decrease due to the ongoing reduction of fossil fuel related emissions going on globally. This will help cut back on air pollution related deaths by the turn of next century.
Unfortunately, the study also shows results of simulations conducted to better understand the effects of fine particulate matter coming from wildfire smoke on human health. The numbers confirm that, as wildfire activity continues to increase in the continental U.S. due to climate change, air quality could worsen in the coming decades. Higher concentrations are expected mainly across the western and southeastern sections of the country (see below), and this could cause human death related to chronic inhalation of wildfire smoke to jump from a current 15,000 per year today, to an alarming more than 40,000 by 2100 given the worst climate change scenario.
Model Predictions of Wildfire Concentration increase in the continental U.S. Simulated decadal average PM2.5 concentrations due to fire emissions from the land model in 2000 and as projected in 2050 and 2100 in the RCP4.5 and RCP8.5 simulations (with the land model fire emissions).
According to the U.S. Environmental Protection Agency, exposure to particulate matter as that generated by wildfires leads to visibility degradation, premature death in people with heart or lung disease, heart attacks, irregular heartbeats, aggravated asthma, decreased lung function and increases respiratory problems. The elderly and children are usually the group at greatest risk.
Between January and July 2018, NOAA has recorded an astonishing 37,718 fires that burned 4.8 million acres of land. The loss of life, vegetation and property has been incredible during the seventh month period, with a tremendous economic cost. In 2017 alone, the U.S. Forest Service spent $2.4 billion in wildfire suppression, a historic high. The information provided in this study is also extendable to other areas of the world where wildfires have been on the rise this 2018, and where climate change will also act to aggravate the situation.
California wildfire satellite image. Courtesy: NOAA.
Between 2000 and 2017 close to 140,000 deaths per year, or 5% of total deaths, were attributed to total particulate matter. 17,000 or 0.7% per year of those deaths were related to particulate matter from wildfires. The new study estimates that by the end of this century, those numbers could double if the worst-case scenario prediction model simulation.
Smoke from Canadian wildfires. Courtesy: NOAA.
Despite efforts to reduce wildfire risks across the country, these continue to increase in frequency, intensity and extension, most likely in relation to climate change impact.
Dr. Pierce and other scientists involved in this preliminary study point out that, given the predicted trend and the potential worsening of the situation of wildfire smoke, we need to start working not only on reducing the impact of climate change on our environment, but also on a plan that will help protect human health in such a potential adverse scenario.