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Our Summer of Fire and the Fires to Come

Thursday, October 19, 2017 By Curtis Johnson, Truthout | News Analysis
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A helicopter prepares to drop water on a fire that threatens the Oakmont community along Highway 12 in Santa Rosa on October 13, 2017. Early morning mandatory evacuations happened on Adobe Canyon Road and Calistoga Rd. (Photo:Genaro Molina / Los Angeles Times via Getty Images)A helicopter prepares to drop water on a fire that threatened the Oakmont community along Highway 12 in Santa Rosa, California, on October 13, 2017. (Photo: Genaro Molina / Los Angeles Times via Getty Images)

Explosive wildfires have raged in Northern California over the last two weeks. Forty-one people are dead, and at least 6,700 structures have been destroyed, making these the most destructive fires in the state's history. Parts of the city of Santa Rosa have burned to the ground. Extremely hot and dry conditions, continuing impacts of the state's drought, and high winds combined to create fires so fast-moving, many residents were forced to flee for their lives with only minutes notice. Tens of thousands have been forced to evacuate. In the last several days, better weather has been helping firefighters fight the blazes, though many are still continuing. Air quality in the region has been called the worst in recorded history due to wildfire smoke.

The fires in Northern California come after a summer of infernos and smoke spanning the West.

It began in Seattle on August 1, 2017. Coming out of work that day, I looked around to try to fathom why the entire atmosphere was thick with haze. Maybe the city's smog had suddenly become abominably worse for unexplainable reasons? Looking around, I noticed it was smoke that lay everywhere. It filled my throat and lungs. The world seemed suddenly wrong, without sense.

These days, and especially this summer, living on Earth feels like existing in dread of the next environmental apocalypse. That day, it felt like it had arrived.

That night, I heard the news. Smoke from wildfires in British Columbia was blanketing the area.

For the next two weeks, it was hard to take a breath outside. The air was acrid, lung-burning. The blue, fresh summer skies Seattle is known for were extinguished. Being outside felt like walking in a stagnant, dead, smoky bubble. The sun and moon eerily appeared through a deep haze, orange or blood red. It was like living in an alternate universe. The smoke returned throughout August and early September.

The Seattle Times said that the region's "natural air conditioning," marine air blown by winds from the west, had broken down. Air quality levels in August plunged so severely, at times Seattle and Portland had air quality worse than Beijing. Elderly people, children and those with compromised respiratory systems were warned to avoid going outside. The general population was told to avoid strenuous outdoor exercise.

I was happy to get out of town on August 11 to head for the Oregon coast and hiking in the Redwoods in Northern California. I looked forward to being able to breathe fresh air again. But it became clear the smoke went way beyond Washington State. As we drove into Eugene, giant plumes of white smoke billowed out of the Willamette National Forest to the east. Further south, more clouds filled the sky from the North Umpqua complex fire. Driving down Highway 101, we came to Brookings on the Pacific coast at the southern tip of Oregon. Smoke choked the town. A fire up the Chetco River had just "blown up" and was spreading in all directions. A few days later, we heard that people were being evacuated immediately due to the fires' rapid spread, in certain spots all the way down to the ocean.

Arriving in Redwood National Park, we were amazed to see the skies there clouded with smoke. In the late afternoon in the Tall Trees Redwood Grove, rays of sunlight angling through smoke and off the trees turned the grove a beautiful but surreal red. Coming home in late August, Oregon was smothered in smoke far thicker than it had been in Seattle, from the southern border almost to the northern. It was hard to imagine people having to try to live and function every day in this.

Summer of Heat and Western Fire

This summer, Seattle broke records for the driest in recorded history, the most consecutive days without rain -- 55 -- and also tied for the warmest summer on record.

Similar conditions were present throughout the West. High-pressure systems repeatedly set up and refused to budge along the north Pacific coast or slightly onshore, and blocked any developing weather systems from the west. After weeks without rain, forest brush and understory that had grown thick after an unusually wet winter withered and dried to a crisp. It was like jet fuel awaiting a match. It was only a matter of time until lightning strikes from dry storms, as well as humans, set things alight.

Scorched by record temperatures, British Columbia (BC) went up in flames in July. Fires raged all summer and 1.2 million hectares burned -- the equivalent of 4,680 square miles -- an area almost as large as the state of Connecticut. The area burned exceeded the yearly average of area burned in BC from 2006-16 by almost 10 times.

In Oregon this summer, a Rhode Island-sized area went up in flames. The Chetco Bar Fire scorched old-growth redwoods in a protected grove at the northern edge of the Redwoods range, severely burning 25 percent of the trees. Another major fire was one along the Columbia River Gorge in northeast Oregon. Started by fireworks on September 2, the fire was fanned by extreme heat and easterly winds. It exploded. Dozens of hikers were forced to hike for their lives to escape. Embers crossed the Columbia River and set off new fires in Washington.

In late August and September, offshore winds created by high pressure inland pulled in more smoke to the Seattle area, now from Washington's own wildfires. Ash fell from the sky, reminding people of the volcanic explosions from Mt. St. Helens in 1980.

Health Impacts of Wildfire Smoke

The smoke didn't just make life miserable at times this summer for the millions of people throughout the West; it was downright unhealthy.

Joshua Benditt, a pulmonologist with the University of Washington Medical Center in Seattle, said he was getting many calls from his patients with lung problems due to the wildfire smoke. Benditt said the poor quality of air from the smoke meant, "It's very difficult for patients with asthma or Chronic Obstructive Pulmonary Disease (COPD), and even some other kinds of lung diseases. It's quite irritating to them and it can cause coughing and wheezing and actually even respiratory failure."

Bonnie Henry, a deputy provincial health officer in BC, told the Vancouver Sun in August that emergency calls and hospital visits had increased 20 to 50 percent among people with respiratory and other health conditions.

In the inland regions closer to the fires, the air was worse than on the coast. Sarah Coefield, an air quality specialist with the Missoula City-County Health Department, described how desperate the situation was becoming for people in Seeley Lake, Montana where elderly, children and sick people were choking on smoke.

These types of conditions existed to varying degrees for weeks throughout the West. Air quality values ranged from "unhealthy for sensitive groups" to "very unhealthy" and worse. In early September in Spokane, Washington, air quality reached hazardous levels for several days.

satellite image from NASA on September 5 showed smoke being blown across the US by the jet stream. NASA said, "Smoke from wildfires can be very dangerous. A 2017 Georgia Tech study showed the smoke from wildfires spew methanol, benzene, ozone and other noxious chemicals into the atmosphere." This study directly measured the amount of emissions from several Western wildfires of some of these potentially dangerous gases, as well as particulate matter pollution that is a mix of microscopic solids and liquid droplets. The study found that the particulate pollution from wildfires, already known to be a large source of particulate pollution in the West, was actually three times worse than previously thought.

A 2016 study, called a "Critical Review of Health Impacts of Wildfire Smoke Exposure" found that globally, the estimated premature mortality caused by wildfire smoke is 339,000 people yearly. High levels of particulate matter in the air from wildfire smoke have led to increases in deaths in Malaysia, Russia and Australia. The study drew a clear connection between wildfire smoke exposure and increased morbidity for people with asthma, COPD and general respiratory problems.

The Georgia Tech study cites other scientific studies that have linked particulate matter (PM) from wildfires to increased respiratory and cardiovascular diseases. While more research is required to fully resolve the whole picture of health impacts of PM in humans, the health impacts from fire smoke is clearly cause for real concern, when literally millions of people are living for weeks at a time in regions choked with wildfire smoke.

Climate Change and Increasing Forest Fires

Wildfires have been a natural occurrence in the history of forests over many, many millennia. In many ways, fires have played a crucial role in helping regulate and regenerate the health of the forest. Natural variation in weather patterns is one factor in creating conditions for wildfires. But what has been happening over the last several decades is far from normal.

Mike Flannigan, director of the Western Partnership for Wildland Fire Service at the University of Alberta, says the "evidence is becoming more and more overwhelming" of the link between climate change and increasing fires globally. The length of fire seasons worldwide increased by 19 percent from 1978 to 2013, due to longer periods of warm and dry weather in a quarter of the world's forests. While the pattern is not uniform, various parts of the world are seeing clear changes over the last decades, according to Flannigan, including Alaska, Siberia, the boreal forests of Canada and elsewhere.

In the Western US, the length of the wildfire season has increased from five months long in the 1970s, to seven months today with 2015 being the worst wildfire season in the West on record as tracked by the National Interagency Fire Center, with over 10 million acres burned. As of October 15, the amount of land burned in 2017 would rank third highest. According to the EPA, of the 10 years with the largest acreage burned, nine have occurred since 2000.

In the Pacific Northwest as a whole, temperatures have risen 1.5°F since 1920. Extremely warm temperatures and drought mix with historically low amounts of winter snowpack to create conditions setting the table for fire.

The connection of climate change and a warming planet to increasing forest fires isn't just confirmed by observational statistics. Scientific studies have started quantifying the contributions of a warmer planet to increasing fires. A 2016 study in the Proceedings of the National Academy of Sciences demonstrated that over half of the increases in "fuel aridity" (metrics that measure the degree of lack of moisture in fuels) since the 1970s, and a doubling of the amount of forest area burned since 1984 were due to human-caused climate change. A 2017 study in the same journal concluded global warming was responsible for increasing the severity and probability of the hottest monthly and daily events in 80 percent of the globe that they were able to study.

In a sense, the relationship isn't rocket science, but it is basic science. Warming temperatures means warmer air, and warmer air holds more moisture, sucking it out of plants and trees making them drier and more likely to ignite and readily burn. When this happens over whole regions of millions of acres, these conditions predispose regions to burn more readily. When the warmth and dryness lasts for longer periods of time, the time when wildfires happen also lengthens.

There are other ways in which climate change is contributing to increasing fires in the West. Lightning strikes are increased by warmer temperatures. It's estimated that for every degree Celsius of warming, strikes increase by about 12 percent.

Furthermore, bark beetle infestation of forests is spreading northward and to higher elevations throughout the West as the planet warms. As winters become warmer and spring comes earlier, conditions for beetle survival increases. Drought-induced stress severely weakens trees' ability to fend off beetles. Beetles interfere with a tree's nutrient delivery and this can kill trees, providing more raw fuel for fires. The beetle infestation has killed tens of millions of acres of forest in North America, and is the largest known insect infestation in North American history.

Human-caused activity is contributing in other ways to forest changes and fire increases.

Forest and other natural habitat continues to be eaten up by new housing and sprawl, driven by the inability of capitalism to restrict development and protect natural areas. Forest Service policy over many years has been to suppress fires, and this has contributed to a build-up of large amounts of fuel on public lands. As human habitation continues to encroach on forests, more fires are sparked. The US Forest Service is also increasingly pushed to try to fight fires to protect houses and towns, in some cases further adding to build-up of fuel. Many foresters are advocating that more scientific criteria be used to differentiate when and which fires should be fought, and which should be allowed to burn up accumulated fuel and return the forests to a more natural fire cycle.

The 2017 Fires and the Larger Picture of a Changing Climate

The smoke and fires this summer were a wake-up call about how quickly things can change in the natural environment and how large the stakes are. But is this devastating summer just the beginning of much worse things to come? And if this is the harbinger of the future, what will this mean for the health of humans and ecosystems?

This summer has been one of truly devastating "natural" disasters overall. Intriguing and important scientific debates emerged from this hurricane season, including over whether global warming was causing more extreme and long-lasting weather events, such as Hurricane Harvey's stall over Houston that caused record rainfalls.

Jennifer Francis, a research professor at Rutgers University, has been studying the relation between the warming of the Arctic, the loss of sea ice and changes that are being observed in weather patterns in the Northern hemisphere, particularly at certain times of the year.

She has advanced a theory that the warming of the Arctic is causing the jet stream to wobble at certain times, creating big waves that draw warmer air up into the Arctic from the southern latitudes. Francis believes that with these big waves, which have been observed, the jet stream is also weakened in its flow from west to east. The jet stream then becomes more susceptible to any obstacles in its path -- physical ones, such as mountain ranges, but also areas of warm temperature, for example. The weakened, wavy jet stream leads to weather patterns that are more persistent. The main cause of this phenomenon is the way in which global warming is occurring more rapidly in the Arctic, lessening the temperature difference between the Artic, and the mid-latitudes.

These phenomena are also further warming the Arctic and melting more sea ice via a number of feedback loops.

Truthout asked Francis via email if this Arctic warming may also be responsible for hot, dry weather patterns that have occurred more frequently in the West over the last several years in summer, contributing to such massive wildfires.

She replied, "There are several new papers that connect Arctic warming and sea-ice loss in the Pacific sector of the Arctic with a strengthened Pacific ridge in the jet stream (large northward bulge), but the mechanism is not simple."

"It appears that there are two factors that need to happen simultaneously to create the strong, persistent ridge that has been so prevalent in recent years along the western coast of North America. One factor is the natural occurrence of a ridge in this location, owing usually to warmer-than-normal ocean temperatures along the west coast -- e.g., a pattern known as a positive Pacific Decadal Oscillation. If there is also substantial ice loss/warming in the Pacific Arctic sector, that ridge tends to be strengthened, which makes it more persistent. This favors the conditions conducive to wild fires: dry and hot."

This link is alluring, if not yet definitively proven. Truthout also spoke with Nick Bond, research meteorologist with the Joint Institute for the Study of the Atmosphere and Ocean at the University of Washington. He said that the weather pattern we saw on the west coast this summer with the persistent ridge of high pressure was very unusual, but, "There's plenty of internal variability in the system -- I'm kind of reluctant, one particular weird year, to ascribe too much to that, but on the other hand, this weather we're having, is the kind of weather we expect to be more common in future decades ... in the long term maybe this is something we better get used to."

So, whether this summer's pattern of persistent high-pressure ridges and abnormally hot, dry weather is already a result of climate change enhancing natural variation, or if it's a harbinger of what's to come, these are important things to watch. Regardless, it's clear that the West, along with the planet, is warming overall, and that this is contributing to the conditions leading to larger wildfires right now. The impact of increasing wildfires on people's health and ecosystems will keep rising, unless serious and emergency measures are taken to counter climate change and its effects.

Copyright, Truthout. May not be reprinted without permission.

Curtis Johnson

Curtis Johnson is a research scientist and freelance writer who has reported on the Gulf oil spill, the Fukushima nuclear disaster, the extinction crisis and the climate crisis, as well as other environmental topics. Follow him on Twitter: @curtisjohnson70.

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Our Summer of Fire and the Fires to Come

Thursday, October 19, 2017 By Curtis Johnson, Truthout | News Analysis
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A helicopter prepares to drop water on a fire that threatens the Oakmont community along Highway 12 in Santa Rosa on October 13, 2017. Early morning mandatory evacuations happened on Adobe Canyon Road and Calistoga Rd. (Photo:Genaro Molina / Los Angeles Times via Getty Images)A helicopter prepares to drop water on a fire that threatened the Oakmont community along Highway 12 in Santa Rosa, California, on October 13, 2017. (Photo: Genaro Molina / Los Angeles Times via Getty Images)

Explosive wildfires have raged in Northern California over the last two weeks. Forty-one people are dead, and at least 6,700 structures have been destroyed, making these the most destructive fires in the state's history. Parts of the city of Santa Rosa have burned to the ground. Extremely hot and dry conditions, continuing impacts of the state's drought, and high winds combined to create fires so fast-moving, many residents were forced to flee for their lives with only minutes notice. Tens of thousands have been forced to evacuate. In the last several days, better weather has been helping firefighters fight the blazes, though many are still continuing. Air quality in the region has been called the worst in recorded history due to wildfire smoke.

The fires in Northern California come after a summer of infernos and smoke spanning the West.

It began in Seattle on August 1, 2017. Coming out of work that day, I looked around to try to fathom why the entire atmosphere was thick with haze. Maybe the city's smog had suddenly become abominably worse for unexplainable reasons? Looking around, I noticed it was smoke that lay everywhere. It filled my throat and lungs. The world seemed suddenly wrong, without sense.

These days, and especially this summer, living on Earth feels like existing in dread of the next environmental apocalypse. That day, it felt like it had arrived.

That night, I heard the news. Smoke from wildfires in British Columbia was blanketing the area.

For the next two weeks, it was hard to take a breath outside. The air was acrid, lung-burning. The blue, fresh summer skies Seattle is known for were extinguished. Being outside felt like walking in a stagnant, dead, smoky bubble. The sun and moon eerily appeared through a deep haze, orange or blood red. It was like living in an alternate universe. The smoke returned throughout August and early September.

The Seattle Times said that the region's "natural air conditioning," marine air blown by winds from the west, had broken down. Air quality levels in August plunged so severely, at times Seattle and Portland had air quality worse than Beijing. Elderly people, children and those with compromised respiratory systems were warned to avoid going outside. The general population was told to avoid strenuous outdoor exercise.

I was happy to get out of town on August 11 to head for the Oregon coast and hiking in the Redwoods in Northern California. I looked forward to being able to breathe fresh air again. But it became clear the smoke went way beyond Washington State. As we drove into Eugene, giant plumes of white smoke billowed out of the Willamette National Forest to the east. Further south, more clouds filled the sky from the North Umpqua complex fire. Driving down Highway 101, we came to Brookings on the Pacific coast at the southern tip of Oregon. Smoke choked the town. A fire up the Chetco River had just "blown up" and was spreading in all directions. A few days later, we heard that people were being evacuated immediately due to the fires' rapid spread, in certain spots all the way down to the ocean.

Arriving in Redwood National Park, we were amazed to see the skies there clouded with smoke. In the late afternoon in the Tall Trees Redwood Grove, rays of sunlight angling through smoke and off the trees turned the grove a beautiful but surreal red. Coming home in late August, Oregon was smothered in smoke far thicker than it had been in Seattle, from the southern border almost to the northern. It was hard to imagine people having to try to live and function every day in this.

Summer of Heat and Western Fire

This summer, Seattle broke records for the driest in recorded history, the most consecutive days without rain -- 55 -- and also tied for the warmest summer on record.

Similar conditions were present throughout the West. High-pressure systems repeatedly set up and refused to budge along the north Pacific coast or slightly onshore, and blocked any developing weather systems from the west. After weeks without rain, forest brush and understory that had grown thick after an unusually wet winter withered and dried to a crisp. It was like jet fuel awaiting a match. It was only a matter of time until lightning strikes from dry storms, as well as humans, set things alight.

Scorched by record temperatures, British Columbia (BC) went up in flames in July. Fires raged all summer and 1.2 million hectares burned -- the equivalent of 4,680 square miles -- an area almost as large as the state of Connecticut. The area burned exceeded the yearly average of area burned in BC from 2006-16 by almost 10 times.

In Oregon this summer, a Rhode Island-sized area went up in flames. The Chetco Bar Fire scorched old-growth redwoods in a protected grove at the northern edge of the Redwoods range, severely burning 25 percent of the trees. Another major fire was one along the Columbia River Gorge in northeast Oregon. Started by fireworks on September 2, the fire was fanned by extreme heat and easterly winds. It exploded. Dozens of hikers were forced to hike for their lives to escape. Embers crossed the Columbia River and set off new fires in Washington.

In late August and September, offshore winds created by high pressure inland pulled in more smoke to the Seattle area, now from Washington's own wildfires. Ash fell from the sky, reminding people of the volcanic explosions from Mt. St. Helens in 1980.

Health Impacts of Wildfire Smoke

The smoke didn't just make life miserable at times this summer for the millions of people throughout the West; it was downright unhealthy.

Joshua Benditt, a pulmonologist with the University of Washington Medical Center in Seattle, said he was getting many calls from his patients with lung problems due to the wildfire smoke. Benditt said the poor quality of air from the smoke meant, "It's very difficult for patients with asthma or Chronic Obstructive Pulmonary Disease (COPD), and even some other kinds of lung diseases. It's quite irritating to them and it can cause coughing and wheezing and actually even respiratory failure."

Bonnie Henry, a deputy provincial health officer in BC, told the Vancouver Sun in August that emergency calls and hospital visits had increased 20 to 50 percent among people with respiratory and other health conditions.

In the inland regions closer to the fires, the air was worse than on the coast. Sarah Coefield, an air quality specialist with the Missoula City-County Health Department, described how desperate the situation was becoming for people in Seeley Lake, Montana where elderly, children and sick people were choking on smoke.

These types of conditions existed to varying degrees for weeks throughout the West. Air quality values ranged from "unhealthy for sensitive groups" to "very unhealthy" and worse. In early September in Spokane, Washington, air quality reached hazardous levels for several days.

satellite image from NASA on September 5 showed smoke being blown across the US by the jet stream. NASA said, "Smoke from wildfires can be very dangerous. A 2017 Georgia Tech study showed the smoke from wildfires spew methanol, benzene, ozone and other noxious chemicals into the atmosphere." This study directly measured the amount of emissions from several Western wildfires of some of these potentially dangerous gases, as well as particulate matter pollution that is a mix of microscopic solids and liquid droplets. The study found that the particulate pollution from wildfires, already known to be a large source of particulate pollution in the West, was actually three times worse than previously thought.

A 2016 study, called a "Critical Review of Health Impacts of Wildfire Smoke Exposure" found that globally, the estimated premature mortality caused by wildfire smoke is 339,000 people yearly. High levels of particulate matter in the air from wildfire smoke have led to increases in deaths in Malaysia, Russia and Australia. The study drew a clear connection between wildfire smoke exposure and increased morbidity for people with asthma, COPD and general respiratory problems.

The Georgia Tech study cites other scientific studies that have linked particulate matter (PM) from wildfires to increased respiratory and cardiovascular diseases. While more research is required to fully resolve the whole picture of health impacts of PM in humans, the health impacts from fire smoke is clearly cause for real concern, when literally millions of people are living for weeks at a time in regions choked with wildfire smoke.

Climate Change and Increasing Forest Fires

Wildfires have been a natural occurrence in the history of forests over many, many millennia. In many ways, fires have played a crucial role in helping regulate and regenerate the health of the forest. Natural variation in weather patterns is one factor in creating conditions for wildfires. But what has been happening over the last several decades is far from normal.

Mike Flannigan, director of the Western Partnership for Wildland Fire Service at the University of Alberta, says the "evidence is becoming more and more overwhelming" of the link between climate change and increasing fires globally. The length of fire seasons worldwide increased by 19 percent from 1978 to 2013, due to longer periods of warm and dry weather in a quarter of the world's forests. While the pattern is not uniform, various parts of the world are seeing clear changes over the last decades, according to Flannigan, including Alaska, Siberia, the boreal forests of Canada and elsewhere.

In the Western US, the length of the wildfire season has increased from five months long in the 1970s, to seven months today with 2015 being the worst wildfire season in the West on record as tracked by the National Interagency Fire Center, with over 10 million acres burned. As of October 15, the amount of land burned in 2017 would rank third highest. According to the EPA, of the 10 years with the largest acreage burned, nine have occurred since 2000.

In the Pacific Northwest as a whole, temperatures have risen 1.5°F since 1920. Extremely warm temperatures and drought mix with historically low amounts of winter snowpack to create conditions setting the table for fire.

The connection of climate change and a warming planet to increasing forest fires isn't just confirmed by observational statistics. Scientific studies have started quantifying the contributions of a warmer planet to increasing fires. A 2016 study in the Proceedings of the National Academy of Sciences demonstrated that over half of the increases in "fuel aridity" (metrics that measure the degree of lack of moisture in fuels) since the 1970s, and a doubling of the amount of forest area burned since 1984 were due to human-caused climate change. A 2017 study in the same journal concluded global warming was responsible for increasing the severity and probability of the hottest monthly and daily events in 80 percent of the globe that they were able to study.

In a sense, the relationship isn't rocket science, but it is basic science. Warming temperatures means warmer air, and warmer air holds more moisture, sucking it out of plants and trees making them drier and more likely to ignite and readily burn. When this happens over whole regions of millions of acres, these conditions predispose regions to burn more readily. When the warmth and dryness lasts for longer periods of time, the time when wildfires happen also lengthens.

There are other ways in which climate change is contributing to increasing fires in the West. Lightning strikes are increased by warmer temperatures. It's estimated that for every degree Celsius of warming, strikes increase by about 12 percent.

Furthermore, bark beetle infestation of forests is spreading northward and to higher elevations throughout the West as the planet warms. As winters become warmer and spring comes earlier, conditions for beetle survival increases. Drought-induced stress severely weakens trees' ability to fend off beetles. Beetles interfere with a tree's nutrient delivery and this can kill trees, providing more raw fuel for fires. The beetle infestation has killed tens of millions of acres of forest in North America, and is the largest known insect infestation in North American history.

Human-caused activity is contributing in other ways to forest changes and fire increases.

Forest and other natural habitat continues to be eaten up by new housing and sprawl, driven by the inability of capitalism to restrict development and protect natural areas. Forest Service policy over many years has been to suppress fires, and this has contributed to a build-up of large amounts of fuel on public lands. As human habitation continues to encroach on forests, more fires are sparked. The US Forest Service is also increasingly pushed to try to fight fires to protect houses and towns, in some cases further adding to build-up of fuel. Many foresters are advocating that more scientific criteria be used to differentiate when and which fires should be fought, and which should be allowed to burn up accumulated fuel and return the forests to a more natural fire cycle.

The 2017 Fires and the Larger Picture of a Changing Climate

The smoke and fires this summer were a wake-up call about how quickly things can change in the natural environment and how large the stakes are. But is this devastating summer just the beginning of much worse things to come? And if this is the harbinger of the future, what will this mean for the health of humans and ecosystems?

This summer has been one of truly devastating "natural" disasters overall. Intriguing and important scientific debates emerged from this hurricane season, including over whether global warming was causing more extreme and long-lasting weather events, such as Hurricane Harvey's stall over Houston that caused record rainfalls.

Jennifer Francis, a research professor at Rutgers University, has been studying the relation between the warming of the Arctic, the loss of sea ice and changes that are being observed in weather patterns in the Northern hemisphere, particularly at certain times of the year.

She has advanced a theory that the warming of the Arctic is causing the jet stream to wobble at certain times, creating big waves that draw warmer air up into the Arctic from the southern latitudes. Francis believes that with these big waves, which have been observed, the jet stream is also weakened in its flow from west to east. The jet stream then becomes more susceptible to any obstacles in its path -- physical ones, such as mountain ranges, but also areas of warm temperature, for example. The weakened, wavy jet stream leads to weather patterns that are more persistent. The main cause of this phenomenon is the way in which global warming is occurring more rapidly in the Arctic, lessening the temperature difference between the Artic, and the mid-latitudes.

These phenomena are also further warming the Arctic and melting more sea ice via a number of feedback loops.

Truthout asked Francis via email if this Arctic warming may also be responsible for hot, dry weather patterns that have occurred more frequently in the West over the last several years in summer, contributing to such massive wildfires.

She replied, "There are several new papers that connect Arctic warming and sea-ice loss in the Pacific sector of the Arctic with a strengthened Pacific ridge in the jet stream (large northward bulge), but the mechanism is not simple."

"It appears that there are two factors that need to happen simultaneously to create the strong, persistent ridge that has been so prevalent in recent years along the western coast of North America. One factor is the natural occurrence of a ridge in this location, owing usually to warmer-than-normal ocean temperatures along the west coast -- e.g., a pattern known as a positive Pacific Decadal Oscillation. If there is also substantial ice loss/warming in the Pacific Arctic sector, that ridge tends to be strengthened, which makes it more persistent. This favors the conditions conducive to wild fires: dry and hot."

This link is alluring, if not yet definitively proven. Truthout also spoke with Nick Bond, research meteorologist with the Joint Institute for the Study of the Atmosphere and Ocean at the University of Washington. He said that the weather pattern we saw on the west coast this summer with the persistent ridge of high pressure was very unusual, but, "There's plenty of internal variability in the system -- I'm kind of reluctant, one particular weird year, to ascribe too much to that, but on the other hand, this weather we're having, is the kind of weather we expect to be more common in future decades ... in the long term maybe this is something we better get used to."

So, whether this summer's pattern of persistent high-pressure ridges and abnormally hot, dry weather is already a result of climate change enhancing natural variation, or if it's a harbinger of what's to come, these are important things to watch. Regardless, it's clear that the West, along with the planet, is warming overall, and that this is contributing to the conditions leading to larger wildfires right now. The impact of increasing wildfires on people's health and ecosystems will keep rising, unless serious and emergency measures are taken to counter climate change and its effects.

Copyright, Truthout. May not be reprinted without permission.

Curtis Johnson

Curtis Johnson is a research scientist and freelance writer who has reported on the Gulf oil spill, the Fukushima nuclear disaster, the extinction crisis and the climate crisis, as well as other environmental topics. Follow him on Twitter: @curtisjohnson70.