Researchers predict impacts of wildfire smoke after climate change

Above: Illustration from Harvard/Yale paper about the impacts of wildfire smoke following climate change. The colors indicate the number of smoke waves based on the primary smoke wave definition (cutoff= 6 μg/m3). The map on the left represents the present day (based on 2004-2009 data). The map on the right represents the future under climate change (based on projected data for the years 2046-2051). 

(Originally published at 11:39 a.m. MDT August 16, 2016; edited at 6 p.m. MDT August 17 to include this link to the research paper. We contacted the author and asked for a copy of the document, which we now have on our website for our readers.)

Researchers at Harvard and Yale Universities have written a paper predicting the quantities of wildfire smoke that will be impacting residents of the United States in the years 2046 through 2051. Unfortunately it will cost you $40 to get a copy of the complete results of their research. Open Access to publically funded research is apparently not a priority at Harvard and Yale. (UPDATE: on August 17 we obtained a copy of the paper from one of the authors. But it would still cost $40 to buy it from the journal.)

The information here is obtained from the abstract and one document with supplementary material that was available.

To identify the highest-risk areas, the team used a fire prediction model and advanced atmospheric modeling to separate pollution caused by wildfires from other pollution sources and track the likely movement of smoke. The authors estimate that under future climate change, more than 82 million individuals will experience a 57 percent and 31 percent increase in the frequency and intensity, respectively, of Smoke Waves, which they define as ≥2 consecutive days with high wildfire-specific PM2.5.

Northern California, Western Oregon and the Great Plains are likely to suffer the highest exposure to wildfire smoke in the future. Results point to the potential health impacts of increasing wildfire activity on large numbers of people in a warming climate and the need to establish or modify U.S. wildfire management and evacuation programs in high-risk regions. The study also adds to the growing literature arguing that extreme events in a changing climate could have significant consequences for human health.

A call to Loretta J. Mickley, one of the authors, to ask about access to the publically funded research, was not immediately returned. UPDATE, August 17, 2016: Ms. Mickley did call the following day, and said she was disappointed that Harvard chose a non-Open Access journal in which to place the paper. She said she will send us a copy of the paper and it will also be posted on her web site in the next day or two. We will link to it later. The research was funded, she said, by the Environmental Protection Agency and the National Institutes of Health. In our opinion government agencies that fund research should only do so if the findings are made public at no additional charge.

(UPDATE: we found the paper on Ms. Mickley’s web site and downloaded it.)

The paper’s authors are J.C. Liu, L.J. Mickley, M.P Sulprizio, et al.

Smoke map and Red Flag Warnings

Smoke map 9-15-15
Map showing the distribution of smoke from wildfires, Sept. 15, 2015. AirNow.

Rain on some of the wildfires in the west has reduced the smoke in those areas to a minimum, while the smoke produced a couple of days ago continues to slowly spread east.

The National Weather Service has issued Red Flag Warnings or Fire Weather Watches for areas in Colorado, Nebraska, and Kansas.

wildfire Red Flag Warnings 9-15-15


The Red Flag map was current as of 11:30 a.m. MDT on Tuesday. Red Flag Warnings can change throughout the day as the National Weather Service offices around the country update and revise their forecasts and maps. For the most current data visit this NWS site or this NWS site.

To see the most current smoke reports on Wildfire Today, visit the articles tagged “smoke” at

Research links wildfire smoke with cardiac arrest in men

smoke prescribed fire firefighter
A firefighter is enveloped in smoke while working on a prescribed fire in Hot Springs, SD, March 30, 2013. Photo by Bill Gabbert.

Researchers in Australia have found a link between smoke from bushfires and cardiac arrest in men over 35 in the population of metropolitan Melbourne. We would like to see a study done of wildland firefighters who breathe far more smoke than the residents of Melbourne.

Below is an excerpt from

Men over 35 have an increased risk of cardiac arrest if exposed to poor quality air from bushfires, a new study has found.

Monash University research using data from Ambulance Victoria’s Victorian Ambulance Cardiac Arrest Registry (VACAR) investigated the links between out-of-hospital cardiac arrests and bushfire smoke exposure in metropolitan Melbourne during the 2006-07 bushfire season.

The study, published in the latest edition of Environmental Health Perspectives, found an association between exposure to forest fire smoke and an increase in the rate of out-of-hospital cardiac arrests.

Monash University researchers led by Dr Martine Dennekamp, Department of Epidemiology and Preventive Medicine, saw greater increases in the number of men over 35 years old experiencing cardiac arrests but did not see a significant association in women over 35.

Dr Dennekamp said exposure to smoke from forest fires was a significant health issue in many countries, and it was important to raise community awareness.

“The problem is likely to get worse in the future, as we can expect fires to become both more frequent and more severe,” Dr Dennekamp said.

The state and federal governments not only employ the most wildland firefighters in the United States, but they would also be the ones to fund research like this. One would think they would have a disincentive to discover environmental conditions on the job that adversely affect the health of their employees. Don’t ask the question if you don’t want to know the answer, right? Mitigating the hazard of smoke for firefighters on a wildfire would be extremely difficult. But the least these employers should do is determine exactly the nature and scope of the hazard, and support their employees, and former employees, who suffer from life threatening diseases caused by their jobs.

There have been some papers written and some research has been completed on wildfire smoke, but what is needed is a thorough long term study on wildland firefighters conducted by epidemiologists. Something we first called for in 2010.

A very well known and respected Hotshot Superintendent advised me to frequently complete a CA-1 accident form after breathing lots of smoke on a fire. If you don’t, perhaps 10, 20, or 30 years later it might be hard to convince your employer that one or more of the following conditions were caused by your job: leukemia, testicular cancer, lung cancer, brain cancer, bladder cancer, ureter cancer, colorectal cancer, and non-Hodgkins’s lymphoma. All of those are recognized by the British Columbia government as an occupational hazard for firefighters; they are called presumptive cancers. But the United States government does not.

Other articles on Wildfire Today tagged cancer and firefighter health.

Researchers estimate global mortality from smoke

Wildfire Today recently reported on a study that linked wildfire smoke with increased physician visits. Now other researchers claim they can estimate the number of people that die each year as a result of breathing smoke particulates, PM2.5. Their principal estimate for the world-wide average mortality attributable to smoke exposure for 1997-2006 is 339,000 deaths annually. According to the researchers, the mortality could be substantially reduced by curtailing burning of tropical rainforests, which rarely burn naturally.

Wildfire smoke affected areas
Spatial locations of the 14 terrestrial Global Fire Emission Database (GFED) regions used in global fire emissions modeling. The warm colors (red, orange, pink) represent the fire-affected area. (from the study)

HERE is a link to “supplemental material” which explains the researchers’ methodology. Below, is the abstract from the paper.
Continue reading “Researchers estimate global mortality from smoke”

Researchers quantify effects of wildfire smoke on residents

Researchers in British Columbia took advantage of smoky conditions from wildfires near Kelowna (map) and other areas in southeastern B.C. in 2003 to study the effects of smoke on the residents. The fires that year burned over 67,000 acres, destroyed 238 homes, and forced 33,000 people to evacuate.

The study not only evaluated the particulate data from air quality monitoring stations, but also the human health impacts, especially in urban settings.

Smoke effects, British Columbia 2003
Difference in weekly asthma visits for 2003 versus the average of 2002 and 2004 (when there were few fires in the study area) plotted against the difference in average weekly total PM10 measurements for Kelowna, the largest city in the study area. Bars indicate the weekly sum of 2003 asthma-specific visits minus the averages of the 2002 and 2004 weekly sums of asthma visits. The black line indicates the average weekly TEOM-measured PM10 in 2003 minus the average of weekly measurements in 2002 and 2004. (From the referenced study.)

The researchers found that increases in smoke particulates, PM10, were associated with increased odds of respiratory physician visits and hospital admissions, but not with cardiovascular health outcomes. Residents in Kelowna experienced an increase of 100 micrograms of particulate per cubic meter of air, which resulted in an 80 percent increase in respiratory hospital admissions and a six percent increase in the odds of an asthma-specific physician visit.

Thankfully, the University of British Columbia authors, Sarah B. Henderson, Michael Brauer1, Ying C. MacNab, and Susan M. Kennedy, made the entire paper freely available to the public, honoring the principles of Open Access.

Study: firefighters’ lung function decreases after exposure to smoke

A new study from the University of Georgia found that lung function decreases for firefighters who work on prescribed fires for multiple days and are exposed to smoke. Further, it showed that respiratory functions slowly declined over a 10-week season.

Unfortunately, even though the study was probably funded by taxpayers, you will have to pay a second time see the study’s results. It will cost you $41 to purchase the article that contains the detailed findings uncovered during the research. The University of Georgia decided to pay a private journal to publish the article, rather than placing it on the

Smoke, fire-N-of-Cascade-Rd-2006
Firefighter working in smoke, fire near Hot Springs, SD in 2006. Photo by Bill Gabbert

University’s web site for free. We have written previously about taxpayers not being able to access taxpayer-funded research. Why does the government continue to fund research, if the product of the research is not made available? A call to Luke Naeher, the senior author of the study, was not immediately returned.

Here is a summary of the report, which thankfully, is provided by the University of Georgia at no cost.


December 5, 2011

After monitoring firefighters working at prescribed burns in the southeastern United States, University of Georgia researchers found that lung function decreased with successive days of exposure to smoke and other particulate matter.

“What we found suggested a decline in lung function across work seasons,” said Olorunfemi Adetona, a postdoctoral research associate and lead author of the study published recently in the journal Inhalation Toxicology.

Luke Naeher, senior author and associate professor in the UGA College of Public Health, explained that the study was designed to investigate whether the 26 firefighters experienced a decrease in lung function working at prescribed burns compared with days they spent away from the fires. Previously, researchers had looked only at changes in lung function of wildland firefighters on days with exposure to smoke.

“Over a 10-week season, these workers’ respiratory functions slowly declined,” Naeher said, adding that there is need to investigate the degree to which these declines returned to their baseline after the burn season. Although results of the study show that lung function at the start of two burn seasons in a limited number of nine firefighters in 2003 and 2004 did not vary significantly, more definitive answers relating to the issue of longer term effect of exposure on lung function would require a different study design.

In recent years, the U.S. Forest Service has sought to better understand and improve its occupational exposure limits for firefighters across the country. Most studies have concentrated on burns in Western states where exposure to and composition of wood-smoke particulate matter may vary to some degree when compared with fires in the Southeast, including South Carolina, where the study was done.

Naeher said the study provides some preliminary information regarding the health effects of fine particulate matter exposure that is intermediate between two exposure extremes. On the low extreme lies ambient air levels typical for developed countries, while inhalation of particles by a smoker represents the opposite extreme. Much research in the field has focused on health effects at both extremes. However, the study of exposure at intermediate levels, like that experienced by wildland firefighters, and women and children exposed to indoor air pollution from cook stoves in developing countries is limited. Naeher’s research focuses on these two different populations, and he explains that the study of the body’s response tothese intermediate exposures may now be more urgent. For example, Naeher said, an initiative led by the United Nations Foundation aims to put clean-burning cooking stoves in 100 million homes in developing countries by 2020.


UPDATE: We heard from Luke Naeher on December 14, 2011. He told us that the research was funded by the University of Georgia, and the Department of Energy-Savannah River Operations Office through the U.S. Forest Service. He sent us copies of two research papers that were published in journals owned by Informa, a company with their head office in Switzerland: Personal PM2.5 Exposure Among Wildland Firefighers Working at Prescribed Forest Burns in Southeastern United States, and Lung function changes in wildland firefighters working at prescribed burns. Mr. Naeher said he cannot change the system in place for reporting science in the peer-review literature, but he will always share his published work freely with anybody who asks