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Enviromedics: Wildfire and No Way Out

The following is an excerpt from the book “Enviromedics: The Impact of Climate Change on Human Health” that was recently published by Rowman & Littlefield. By Jay Lemery, MD, and Paul Auerbach, MD “Hot and dry — they go hand in hand. As temperatures climb and rainfall diminishes, the landscape changes. Grass turns brown, leaves...

The following is an excerpt from the book “Enviromedics: The Impact of Climate Change on Human Health” that was recently published by Rowman & Littlefield.

By Jay Lemery, MD, and Paul Auerbach, MD

“Hot and dry they go hand in hand. As temperatures climb and rainfall diminishes, the landscape changes. Grass turns brown, leaves wither and die, and undergrowth is choked off from its life source and becomes brittle. Formerly majestic trees lose limbs, and if the water shortage is profound and prolonged, they die, crack, and fall. Verdant forests become flammable fuel, endless until it burns and is reduced to ashes. 

Humans encroach on forests, notably in what is known as the wildland-urban interface. We very often don’t build defensible dwellings, even though historical experience lets us know with a reasonable amount of precision the circumstances and risks of a specific location under fire-prone weather conditions. When a dry forest goes up in flames, it spews embers and fireballs, and overruns the terrain and dwellings with ferocity unmatched by any other natural disaster. As climate change redefines the new “normal” in our weather patterns, wet places may become wetter and dry places drier. Warm, drier weather is a driver for seasonal wildfires; forests and soil hold less moisture, and there are less water and snowpack to act as a buffer against fire. In the western United States, we’ve seen a pattern that is now replicated worldwide. Wildfire numbers are increasing, and fire seasons are growing longer.

A wall of raging wildfire hundreds of feet tall devours a forest. Credit: J. Baylor Roberts/National Geographic Creative

By far the greatest number of people is put at risk for experiencing one or more effects of wildfires by large swaths of enormous air masses degraded by smoke. These can be the size of an entire western American state during peak fire season and can travel thousands of miles. Wildfire smoke is a mixture of gas and fine particles from burning vegetation and/or building materials and can contain large amounts of carbon monoxide, nitrogen oxides, ozone precursors, particulate matter, and even poisonous mercury precursors. Smoke exposure can cause coughing, shortness of breath, sore throat, eye irritation, runny nose, and sinus pain. It can also trigger wheezing. For persons with active airway disease, smoke exposure can precipitate a full-blown asthma attack. Wildfires can burn for months. Persistent smoke generation can place downward inhabitants at risk for chronic lung irritation, headaches, and fatigue. Such a situation has been linked directly to increased emergency department visits. Persons with preexisting heart of lung conditions risk further stress and the necessity for medical interventions and/or hospitalizations. The very young, elderly and pregnant women are most at risk from wildfire smoke, because their lungs and the developing fetus, respectively, are the most sensitive to the injurious effects of smoke.

Extreme weather events are disruptive and almost always hazardous to human health. From the perspective of those who need to decide whether to take actions that will diminish the likelihood of such events, it is mandatory to understand what they are, how many people they effect, and what would be the benefit to humankind if we were able to cause them to be fewer, less intense, and of shorter duration. Knowing how to survive a wildfire or flood is not nearly as good as not having to endure them.”


“Dry lightning” caused the fire. The storm clouds accumulated a colossal amount of static electricity, which they carried over the hills until the differential between the earth below and sky above provided a leader stroke, followed by the massive discharge contained within the main channel. In the midst of a forest, the taller cluster of trees beckoned to the black bottom of a gray anvil overhead, and Thor could not resist. In a single mighty instant, the match struck in the heavens ignited the ground below.

Rowman & Littlefield

Tom and Sally thought they were prepared. They lived in a log cabin in the woods not far from Bend and had cleared a twenty-foot perimeter around the foundation. Sprinklers were strategically positioned on the roof to soak it down, and the truck was next to the house with a full tank of gas for a quick escape. If fire struck, they would do battle only briefly and leave with their valuables when it became apparent that their dwelling could not be saved. They realized that their evacuation plan was cutting it close, but they knew the forest service roads near their property like the back of their hand.

They had every chance to get out, The fire started five miles away, and the smoke came early, pushed by the wind. It was dense and turned the incandescent sun into an orange ball that you could stare at without having to look away. A neighbor drove up to their home with a truck full of his belongings and told them that everyone in the area had been given instructions to evacuate no point taking chances. No rain was in the forecast, and the winds would shift many times. Helicopters carrying huge bags of water pulled from lakes and planes spraying brightly colored fire retardant chemicals flew overhead. There was no mistaking the gravity of the situation. War was being waged on this fire.

Even though it’s the right thing to do, nobody wants to abandon his home. Tom had been a volunteer firefighter and should have known better. Instead of exercising caution, he mistakenly thought they could tough it out for another fifteen minutes. “We’ll be right behind you,” he assured his friends. That would be the last time they saw each other.

The wall of fire came hard, fast, and unexpectedly from two directions. The inferno burned or melted everything in its path. By the time Tom realized that Sally was not responding to his shouts, she was face down in the backyard, crushed by a fallen tree limb. In less than five minutes, she was burned beyond recognition. In a desperate attempt to save himself, Tom quickly dug a shallow pit in the ground, knelt down, and covered up with an old silver “space blanket.” In a lesser fire, this might have saved his life, but this was no lesser fire. The scalding fire and flames made quick work of Tom, and destroyed his home and thousands of acres of surrounding forest. It was one of dozens of fires triggered by the same weather system, in a pattern that would be repeated more often as weather and fuel combined to create a perpetual fire hazard.”

Credit: Paul Auerbach, left, with Jay Lemery.

Jay Lemery, MD, is Associate Professor of Emergency Medicine at the University of Colorado School of Medicine, Chief of the Section of Wilderness and Environmental Medicine, and an Affiliate Faculty Member of the Colorado School of Public Health. He is a past-President of the Wilderness Medical Society and has provided medical direction to health care providers operating at both poles, most recently serving as the EMS Medical Director for the U.S. Antarctic Program.

Paul Auerbach, MD, is the Redlich Family Professor in the Department of Emergency Medicine at the Stanford University School of Medicine, and Adjunct Professor of Military/Emergency Medicine at the F. Edward Hébert School of Medicine of the Uniformed Services University of the Health Sciences. He is a founder and past-President of the Wilderness Medical Society and elected member of the Council on Foreign Relations. Dr. Auerbach is Editor of the Definitive Textbook Wilderness Medicine and author of Field Guide To Wilderness Medicine And Medicine For The Outdoors. He was the founding Co-Editor of the Journal Wilderness & Environmental Medicine and is one of the world’s leading experts in wilderness medicine and emergency medicine.

Enviromedics is available at Amazon, Barnes & Noble and Books, Inc.

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