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Wildfires, Mudslides in the Wake of Climate Change

“Enviromedics: The Impact of Climate Change on Human Health” by Jay Lemery, MD and Paul Auerbach, MD was published this past October by Rowman & Littlefield. We asked Dr. Auerbach of Stanford University to comment on the aftermath of the recent wildfires in California. By Paul Auerbach The destruction from the wildfires in California (and...

Enviromedics: The Impact of Climate Change on Human Health” by Jay Lemery, MD and Paul Auerbach, MD was published this past October by Rowman & Littlefield. We asked Dr. Auerbach of Stanford University to comment on the aftermath of the recent wildfires in California.

By Paul Auerbach

The destruction from the wildfires in California (and much of the western United States) was notable for its wide extent, rapidity with which the fires spread, and intensity of human tragedy. These fires were part of a much longer fire season attributed to climate change, which included the features that contribute to fire: abundant fuel, hot weather, dry air, and strong winds. The entire nation was reminded that while we can somewhat predict fire seasons, we cannot easily predict the behavior of any given fire. A burning fire causes human health to suffer directly by burns, smoke inhalation, heat-related illnesses, psychological stress, and injuries (such as from falling trees or rescue-related mishaps). Indirect impacts upon human health include “acute on chronic” (such as worsening asthma or other lung disease from poor air quality), events such as heart attacks due to exertion, and fire-related events (such as motor vehicle accidents).

Homes burning in a Lake Arrowhead neighborhood. (ALL PhotographS by Mark Thiessen)

A large fire strips the landscape of vegetation and man-made structures. What was once a neighborhood becomes a burned-out shell. A hillside formerly verdant with trees and shrubs immediately is turned into an ashy, smoky, and ember-filled smooth surface. A slope that could previously absorb and retain water in porous soils and plant roots is now an angled dirt field that with rainfall turns into slick mud, gains weight, loses traction in layers, and slides. Enormous weight fuels a landslide that cannot be stopped as it carries many tons of dirt and rocks that bury everything in its path. This also distributes human and animal wastes from exposed septic tanks and systems, which compounds the problems caused by flooding, which percolates through sewers and bubbles up nasty, harmful bacteria that cause infections and diseases. If chemical or fuel storage has been disrupted, floodwater can carry toxic solvents and industrial substances.

Food must be carefully selected and cleaned as best possible. If mud from slides or carried by swollen streams and rivers reaches the ocean, it can contaminate shellfish and coastal-feeding fish. Contaminated dirt and silt cause infectious gastroenteritis.

What improvements might contribute to less future risk of destruction and death due to wildfires? Of course, we must do everything possible to understand and mitigate unwanted climate change. However, assuming that this will take a while even with the best efforts, we should for the forseeable future anticipate a higher likelihood of conditions that support proliferation of wildfires. Therefore, everyone should build a defensible space around their personal dwelling, particularly if it is in an area that is part of the urban-wildland interface. We should understand what to do regarding escape and personal safety in the event of a wildfire. We should have superb and redundant communications systems to warn people who might be affected by wildfires. We should only build and rebuild in areas that are felt to be safe from a spreading fire or from a mudslide, and with materials and patterns that are state of the art.

Editor’s note: From his book Medicine for the Outdoors, Dr. Auerbach shares advice adapted from the U.S. Forest Service about how to behave in wildland fire country:

High-Risk Situations

The risk for a wildland fire is increased under certain environmental conditions. Pay heed to posted warnings of fire hazard, and don’t venture into the woods unprepared to escape. Be particularly cautious when:

1. There are drought conditions. Low humidity, higher air temperatures, and gusty winds create dry fuel for a fire.

2. You are in an area rich with abundant fuel, such as dead grass, pine needles, shrubs, fallen trees, and the like.

3. You travel through gullies, in canyons, along steep slopes, or in other regions where wind and fuel are ideal for rapid advance of an established fire.

4. Fires have occurred recently in the vicinity.

5. You cannot see the main fire and are not in contact with anyone who can.

6. Terrain and fuels make escape to safety zones difficult.

Standard Fire Encounter Principles

1. Have advance knowledge of weather conditions and forecasts before undertaking an expedition. Don’t travel in hazardous regions in times of high fire risk. Local ranger stations are the best source of information. Never plan an extended journey without leaving an itinerary with the proper authorities. In the event of a fire, try to maintain communication with firefighters or other rescuers.

2. At every campsite, take a few moments to prepare a plan for an evacuation, with at least two escape routes. Be certain that everyone understands the routes.

3. If a fire is in the area, pay attention to it, so that you will know what the fire is doing. Obtain current information on fire status. If there is any chance that it can involve your party, get out early.

4. If you see smoke or fire at a distance, post a lookout to watch for any changes that might indicate increased danger.

5. In all situations, stay calm and act with authority. Give orders concisely and be sure that they are understood. Base all of your actions on the current and expected behavior of the fire.

6. Don’t attempt to fight the fire unless you have provided for safety first. Your primary responsibility is to evacuate all potential victims and provide necessary first aid. In general, it’s best to leave firefighting to professionals. If you become a firefighter, provide for safety first. Determine safety zones and escape routes.

7. Don’t sleep near a wildland fire. If the wind and fire direction change, you may be overcome with smoke and unable to escape.

Fire makes a run up a hill in Running Springs, Calif. 
What to do When Caught in a Wildland Fire

A safe area is one with light or no fuels, such as a rocky surface, marshy area, large area of pavement, center of a sufficiently large body of water, or recently burned area. This last option only works if the distance between the fire and entry into the safe area is short, the fire is advancing slowly, and it is easy to reach the safe area.

1. Try not to panic. This is difficult, but if anything will save your life, it will be a clear head.

2. Don’t move downhill toward a fire, because fires have a tendency to run uphill.

3. Unless the path of escape is clear, don’t start running. Conserve your strength, and seek the flank of the fire. Continually observe changes in speed and direction of the fire and smoke to choose travel away from fire hazards. Be alert, keep calm, and avoid injury from rolling or falling debris.

4. Enter a burned area, particularly one with little fuel (grass or low shrubs). Although there is a chance that the area might burn again, you’re better off here than in an area of fresh fuel. If you have to cross the fire line, cover your skin as well as possible, take a couple of deep breaths, and dash through the lowest flames (less than 5 ft, or 1.5 m, tall and deep and where you can see through them). If smoke is dense, crawl along the ground for better air and visibility.

5. If you cannot enter a burned area, ignite grass or other fine fuels between you and the fire edge. Carry wind-resistant matches for this purpose. After this area burns, step into it and cover your exposed skin with clothing or dirt. This is not an effective technique in areas of heavier fuels.

6. Try to avoid breathing smoke. Hold a moistened cloth over your mouth. If the air is very hot, use a dry cloth (dry heat is less damaging to the lungs than is steam). If you have a choice of clothing, cover your skin with closed-toe shoes, a long-sleeved cotton or wool shirt, cotton or wool pants, a hat, and gloves.

7. Seek refuge from the radiant heat. Take shelter in a trench, in a pond, behind rocks, or in a stream, vehicle, or building. Don’t climb into elevated water tanks, wells, caves, or any other place where you might be trapped or quickly use up the available oxygen.

8. If all else fails and you cannot escape the advancing flames, lie face down on the ground and cover your exposed skin as best possible to shield from radiant heat. This is better than standing or kneeling. If available, a fire-retardant blanket or shield is desirable. Radiant heat can kill a person long before the flames reaches him. When a fire passes over and around a person, heating of body tissues from thermal radiation can be unbearable. Staying calm and not getting up until the fire has substantially dissipated is critical.

9. If you are near a vehicle, and there is no route for escape, it’s better to stay in the vehicle than to run from the fire. Try to position the vehicle in an area of little natural vegetation. Avoid driving through dense smoke. Turn off the headlights and ignition. Roll up the windows, close the air vents, and shield yourself from the radiant heat by covering up with floor mats or hiding under the dash. Stay in the vehicle as long as possible (it’s rare for a gasoline tank to explode, and it takes a minute or two for the vehicle to catch on fire). Don’t be overly alarmed if the vehicle rocks, or if smoke and sparks enter the vehicle. When the fire passes, cover your nose and mouth with a moistened cloth to avoid inhaling fumes from burning plastics and paint. Use urine if no other liquid is available.

10. If you are in a building and a fire is approaching, attach hoses to external water fixtures to achieve as much water spray coverage as possible. Place lawn sprinklers on the roof or use the hoses to soak down the roof. Put a ladder outside that will reach the roof. Locate and position buckets, rakes, axes, and shovels. Soak down shrubs and combustible foliage within 20 ft (6 m) of the building. If you have time, also do the following:

• Close windows, vents, doors, and blinds. Remove combustible drapes and window dressings. Close doors inside the house to prevent drafts.

• Turn off the gas at the meter. Turn off all pilot lights (heater, range, oven, and so on). Turn off any propane tanks.

• Open the fireplace damper and close the fireplace screens.

• Place water in containers to fight the fire. A wet mop may be used to extinguish sparks and embers.

• Turn on a light in each room (for visibility if smoke accumulates).

• Move flammable furniture away from windows and sliding glass doors.

• Move flammable patio furniture indoors or far away from the building.

• Keep all of your pets in one room.

• If you have a car or truck, back it into the garage or park it in an open space facing the direction of escape. Shut the doors and roll up the windows. Leave the key in the ignition. Close the garage door(s) and windows, but leave them unlocked. Disconnect any automatic garage door opener.


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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