Research Confirms Wildfires Are Declining Amidst Warming

Published September 24, 2020

Over the past few weeks, thousands of “news” stories have claimed human-caused climate change has increased the frequency and severity of wildfires in the western United States and around the globe. The problem is, the data doesn’t support them. That’s a big problem for those making these claims.

Peer-reviewed research consistently shows wildfires are less frequent and severe on average annually now than they were in the early part of the 20th century, despite the world having warmed modestly over the past 150 years, and they are much, much less frequent and severe than in the ancient past.

A 2012 study published in the Proceedings of the National Academy of Sciences found wildfires in the western United States attained “the lowest levels … during the 20th century and during the Little Ice Age (LIA, ca. 1400–1700 CE [Common Era]). Prominent peaks in forest fires occurred during the Medieval Climate Anomaly (ca. 950–1250 CE) and during the 1800s.”

Let’s look at California for a moment, since so many of the apocalyptic claims about wildfires “fueled” by climate change in recent years focus on the fires in that state. Research shows massive wildfires regularly swept through the region historically. A 2007 paper in the journal Forest Ecology and Management found more than 4.4 million acres of California forest and shrubland burned annually before European colonization in the 1800s, far more than the area of California that has burned annually since 2000, which has ranged from 90,000 acres to 1,590,000 acres per year. The historic annual average for the state is more than double the amount of acreage lost to wildfires this year.

Wildfires have declined in number and severity since the early 1900s, data from the U.S. National Interagency Fire Center (NIFC) show. Using data on U.S. wildfires from as far back as 1926, NIFC reports the numbers of acres burned is far less now than it was throughout the early years of the 20th century, with the current acres burned running about 1/4th to 1/5th of the record values that occurred in the 1930s.

The global wildfire data is just as clear. In a study published in Philosophical Transactions B (PTB), a journal of the Royal Society, the authors write, “many consider wildfire as an accelerating problem, with widely held perceptions both in the media and scientific papers of increasing fire occurrence, severity and resulting losses. However, important exceptions aside, the quantitative evidence available does not support these perceived overall trends. Instead, global area burned appears to have overall declined over past decades, and there is increasing evidence that there is less fire in the global landscape today than centuries ago.”

In particular, “Analysis of charcoal records in sediments and isotope-ratio records in ice cores suggest that global biomass burning during the past century has been lower than at any time in the past 2000 years. … For example, data for Europe and Australia/New Zealand show a strong decline in area burned of 5 percent yr−1, despite the latter region experiencing the largest annual area burned in the final year of the observation period,” write the authors of the PTB study.

In his new book, False Alarm, Bjorn Lomborg notes research shows “[t]here is plenty of evidence for a reduction in the level of devastation caused by fire, with satellites showing a 25 percent reduction globally in burned area just over the past 18 years.” This data comes from a 2017 study subtitled “Burn less baby, burn less,” published in Science.

“In total, the global amount of area burned has declined by more than 540,000 square miles, from 1.9 million square miles in the early part of last century to 1.4 million square miles today,” Lomborg writes.

In a recent study published in Environmental Research Letters, a research team from the University of Albany used satellites to examine wildfire trends across Central Africa and found a significant decline in area burned annually. The data from Africa is important because fires on that continent account for a disproportionately large percentage of the global acreage burned and carbon dioxide emitted annually.

The University of Albany’s press release describing the study states,

Referred to as the “fire continent” by NASA, Africa is surprisingly a crucial hot spot for blazes. Global satellite images have shown that on an average August day, it is home to at least 70 percent of the 10,000 wildfires burning worldwide and 50 percent of fire-related carbon emissions.

However, a new observational study has revealed a decreasing burned area trend that could impact African ecosystems.

The study, led by a team of researchers at the University at Albany, analyzed fires in Central Africa from 2003 to 2017 using a combination of satellite-derived burned area data, reanalysis data, and machine learning techniques. Results showed a total decline in burned area by about 1.3 percent per year. The decline, both in fire frequency and size, occurred mostly in tropical savannas and grasslands.


With small, localized exceptions, anywhere one cares to examine—and by examine, I mean look at the actual data, not the day’s misleading headlines and understandably heart-wrenching photographs—one finds wildfires across the world have declined in number and severity over the past 150 years, largely because of increased active suppression by governments and inhabitants living in or near wildfire-prone regions, using modern firefighting technologies. Where wildfires have begun to expand a bit, after years of decline, it is due to poor public policies that have allowed untreated fuel to build up—brush and historically unusually dense stands of trees—under an approach pushed by radical environmentalists under which nature is allowed to “take its course.”

—    H. Sterling Burnett

SOURCES: University of Albany; Environmental Research Letters; Climate at a Glance; Philosophical Transactions B; Science; Global Warming Policy Foundation




A research paper published in JGR Atmospheres, a peer-reviewed journal published by the American Geophysical Union, reports temperatures in the McMurdo Dry Valleys in Antarctica declined significantly between 1986 and 2006, thereafter fluctuating but displaying no discernible trend upward or downward. McMurdo is the largest ice‐free region of the continent, consisting of approximately 1,500 square miles of deglaciated mountain desert.

The mean air temperature for the McMurdo as a whole, averaged across all 14 operational meteorological stations distributed throughout the valleys, was −20°C, with the mean annual air temperatures on the valley floors ranging between −15°C and −30°C, depending upon the station location. Surface air temperatures decreased by 0.7°C per decade from 1986 to 2006 at Lake Hoare station, the station with the longest continuous record, “after which the record is highly variable with no trend.” All the other stations having sufficiently long records showed similar temperature trends.

SOURCE: JGR Atmospheres (behind paywall)


E&E News reports California is cranking up its fossil fuel use once again to deliver electricity in the midst of the state’s ongoing wildfires. The California Independent System Operator (CISO) says electricity delivered to the system from solar panels in the state has dropped by a third as the smoke from the fires reduces the amount and quality of sunlight reaching the solar cells.

“With the wildfires that are burning in California and the Pacific Northwest, it’s very clear that with the smoke that’s in the air, there is a reduction in the amount of light that can reach solar panels,” Michael Bolen, project manager for solar generation at the Electric Power Research Institute, told E&E News. “That is because of the way the solar spectrum changes as it passes through the particulates in the air, that also affects how much PV [solar photovoltaic] modules can produce.”

Even after the wildfires are extinguished, their impact on solar power delivery in the state is likely to linger because of the ash from the fires, Bolen says.

“All those ash [and] smoke particles have to settle somewhere,” Bolen said. “If they land on the PV modules, then they could block light from entering the modules.”

Ernest Moniz, Ph.D., secretary of energy for President Barack Obama, says the rolling power blackout CISO imposed on California during the August heat wave and the power loss amidst these fires, which reoccur annually, show “California policymakers were deluding themselves if they thought that a combination of solar power and battery storage could fill the state’s electricity needs through the coming decade [and help it] hit the goal of delivering 100 percent of its electricity from carbon-free sources by 2045,” E&E News reports.

“Right now there is a shortage of [generating] capacity,” Moniz said at a recent conference, “citing ‘tremendous challenges’ with addressing the variability of renewable power on both hour-to-hour time scales and wider shifts in seasonal demand,” according to E&E News.



In the wake of Hurricane Laura making landfall in Louisiana, numerous media pundits claimed it marked a record and proved hurricanes striking Louisiana were becoming more frequent and severe because of climate change. An examination of the data for hurricanes striking Louisiana since 1851, including Laura, conducted by Roy Spencer, Ph.D., the principal research scientist at the University of Alabama in Huntsville, shows this is untrue. There is no evidence climate change, however defined, has caused Louisiana residents to suffer more from hurricanes, Spencer finds.

Although “hurricane damage has increased, as people flock to the nation’s coasts and associated infrastructure increases, [the increased damage is] not because the weather has gotten worse,” Spencer writes.

The old adage that a picture is worth a thousand words applies to Spencer’s analysis. Spencer assembled the two graphs below using data covering “all of the hurricanes affecting Louisiana in the last 170 years in the National Hurricane Center’s HURDAT database.” They show no long-term increase in either the number of hurricanes or their intensity since 1851.


Neither the number nor intensity of hurricanes impacting Louisiana since 1851 has experienced a long-term increase, assuming major Hurricane Laura (2020) makes landfall as a Cat4 storm. Dashed lines are the linear trends.

Those graphics tell the tale. The short version is there is no evidence of climate change inducing a hurricane increase.

SOURCE: Dr. Roy Spencer

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