By Henry Worobec
On Labor Day, City Beach was empty. The air stung like the bad side of a camp fire. Smog hid the mountains and filtered the trees with sepia haze. While this eerie, natural event strained the Northwest for fresh air this past weekend, it will likely be worse in years to come, so a collaborative of chemists race to find out more about the deadly emissions of wildland fire.
In Sandpoint, the worst wildfire-induced smog event in recent memory rolled into town on Labor Day — a day that usually marks the last great boom in tourism revenue for the summer. This year, boat rental companies closed down for lack of visibility and businesses in general lost anticipated revenue from the unfriendly atmospheric conditions. The Environmental Protection Agency rated the air quality “hazardous,” advising all people to stay indoors and avoid physical exertion.
The health effects of wildland fire smoke come largely from the particulate matter in the smoke: the solid particles and liquid droplets that are suspended in the air. The size of these particulars is less than one 60th of the diameter of a human hair. At that size, they can be inhaled into the deepest recesses of the lung, posing greater health risks than larger particles. When these particles are inhaled they pose threats such as reduced lung function, bronchitis, exacerbation of asthma, aggravation of pre-existing respiratory and cardiovascular diseases and premature death.
Only a few people braved the Labor Day smog to recreate. When asked why he was out in the smoke, Bob Libbey, retired school teacher said, “Because the wind is great.”
Libbey had been waiting for weeks for the strong winds needed to go windsurfing. He mentioned the disorienting feeling of surfing out into the lake, losing sight of shore through the smoke, and trusting the wind to carry him back to the beach.
“I can’t remember the smoke ever being this bad before,” Libbey said. He has lived in Sandpoint since 1972.
The wind that brought great windsurfing conditions came from a low-pressure system. It stoked the fires and transported their emissions throughout the region. If you had to pin blame for the smoke on one thing, you could blame it on the weather. But that answer misses the larger context of what’s happening and why Sandpoint should prepare for greater drop offs in tourism revenue in the summers to come.
Most scientists expect the severity and frequency of wildland fires to rise, so the same can be expected of the smog produced by fires. For one thing, half a century of wildland fire management policy focused on fighting every fire left forests over stocked with fuels. Depending on the dominant tree species, forest ecology naturally relies on burn events to occur every seven to 14 years. It is part of the natural cycle that keeps a forest healthy. Only in the past 30 years or so has the United States Forest Service adopted policies that let fires burn, containing them only to protect homes and infrastructure.
The other major factor is that summers are trending longer, hotter and drier.
So what is really known about this increasing threat, and what’s being done to better understand it?
“Fires are probably the least known of the three major influences on the atmosphere,” said Bob Yokelson, a chemist at the University of Montana. The other two major influences on the atmosphere are the emissions from vegetation and the emissions from automobiles and factories.
Yokelson collaborates on a five-year intensive study on the air quality and climate effects of fire emissions called FIREX – Fire Influence on Regional and Global Environments Experiment. The study, led by the National Oceanic and Atmosphere Administration, kicked off with preliminary research at the Forest Service’s Rocky Mountain Research Station Fire Sciences Laboratory in Missoula, Montana last October.
Chemists from around the country converged to light stuff on fire. Inside an old building that looked like a repurposed Willy Wonka Chocolate Factory, they helped each other set up gizmos and gadgets in every nook and cranny, along wind tunnels, in the observation rooms, outside in mobile laboratories, up a rickety service elevator and around the grated platform on top of the worlds’ largest climate-controlled Wind Tunnel and Combustion Laboratory.
In the center of the combustion lab, a 66-foot retractable exhaust flue reached down from the ceiling. It’s thick metal funnel looked to be about the size needed for a UFO to abduct a cow. Beneath it, the team burned different materials representing various forests in the western United States on a platform of cinder blocks contained by chicken wire. They measured the different chemicals and particles emitted at different stages of the burns and under different climate conditions with four burns a day for six weeks straight. To blow off steam in between burns, the crew took turns learning how to use principle investigator Jim Roberts’ unicycle.
The testing in the lab helped them acquire baseline data for the wide range of variables in wildland fires. In the next phase of the research project, planes like NOAA’s “Hurricane Hunters,” will fly over real wildland fires to sample emissions.
Amongst the many variables, the stages of a fire –flaming and smoldering– may be the easiest to conceptualize. Flaming is most prominent at the beginning of most fires and is characterized by bright flames and darker smoke, while smoldering is often a later stage and indicated by white smoke. At a campfire, flaming is for roasting marshmallows, and smoldering is for playing musical chairs to avoid the smoke that irritates your eyes and respiratory tract.
“In general, flaming makes more oxidized species and particles that warm the climate, while smoldering makes more reduced compounds and particles that may cool the climate,” Yokelson said. “The products of flaming and smoldering have different impacts and they interact with each other in the atmosphere in complex ways that require more study to understand.”
The relationship described by Yokelson can be seen in the correlation of spikes and dips in data graphs of all the different research focuses at FIREX. To get a clear sense of this, consider the variation between carbon dioxide and carbon monoxide emissions. At the beginning of the burn, when the fire is predominantly flaming, carbon dioxide spikes. As the fire runs its course and moves into the smoldering phase, the carbon dioxide subsides and carbon monoxide rises. By investigating these processes, the FIREX chemists learn more about how fires affect the climate.
The project includes both air quality and climate effects, because they are interconnected.
“I think most scientists agree that the warming climate (regardless of its cause, but it’s probably mostly humans) will increase the amount of fires, which would make bad air quality due to fires more common,” Yokelson said.
Further research, like that of the FIREX project, will help inform wildland fire management decisions, air quality forecasting and safety precautions, but the crux of the issue of air quality hazards from fire and its effects on local economies is the greater predicament of adapting for climate change.
Henry Worobec is a freelance writer and filmmaker, focused on natural resource issues in the Rocky Mountain West.