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Thursday, September 17, 2020

GWPF Newsletter: Satellite Observations Reveal Decreasing Trend in Global Wildfires

 





Solar Cycle 25 To Repeat Low Cycle 24, Scientists Predict

In this newsletter:

1) Satellite Observations Reveal Decreasing Trend in Global Wildfires
GWPF Observatory, 16 September 2020 

2) Solar Cycle 25 To Repeat Low Cycle 24, Scientists Predict
GWPF Observatory, 16 September 2020

 
3) Research Reveals “Climate-Complacency” Across Europe
University of Warwick, 14 September 2020
  
4) Bjorn Lomborg: Sorry, Solar Panels Won’t Stop California’s Fires
New York Post, 14 September 2020
 
5) Michael Shellenberger: Forests That Survive Megafires Prove Good Management Trumps Climate Change
Forbes, 13 September 2020
  
6) And Finally: China Moves Away From Banning Petrol Cars
Bloomberg, 16 September 2020

Full details:

1) Satellite Observations Reveal Decreasing Trend in Global Wildfires
GWPF Observatory, 16 September 2020
 
While wildfires in the Western U.S. continue to rage, satellite observations over the last 20 years have revealed a decreasing trend in global wildfires. What’s going on?












Source: NASA Earth Observatory
 
As strong winds and hot air continue to propel wildfires across the Western U.S. states of California, Oregon and Washington state, politicians, activists and researchers quarrel violently about the main causes of these disasters and how to reduce the risk of wildfires in the future.

There can be little doubt that drought conditions and high temperatures are exacerbating these wildfires. However, over recent decades human activities such as land management and agriculture, increasing population density and active fire suppression have succeeded in significantly reducing the global areas burned by wildfires, despite the rise in global temperatures.
 
To understand why some arid and semi-arid regions of the world have managed to reduce wildfires in the face of rising temperatures, such as Mediterranean Europe, while other regions haven’t succeeded to do so, will be crucial to risk reduction policies.
 
Below we have selected recent research papers, based on satellite observations, which reveal the decreasing trend in global wildfires and the most likely reasons for these encouraging developments.
 
Global trends in wildfire and its impacts: perceptions versus realities in a changing world





 




Abstract: Wildfire has been an important process affecting the Earth’s surface and atmosphere for over 350 million years and human societies have coexisted with fire since their emergence. Yet 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. Regarding fire severity, limited data are available. For the western USA, they indicate little change overall, and also that area burned at high severity has overall declined compared to pre-European settlement. Direct fatalities from fire and economic losses also show no clear trends over the past three decades. Trends in indirect impacts, such as health problems from smoke or disruption to social functioning, remain insufficiently quantified to be examined. Global predictions for increased fire under a warming climate highlight the already urgent need for a more sustainable coexistence with fire. The data evaluation presented here aims to contribute to this by reducing misconceptions and facilitating a more informed understanding of the realities of global fire.

Full paper
 
 
A human-driven decline in global burned area





 





Abstract: Fire is an essential Earth System process that alters ecosystem and atmospheric composition. Here we assessed long-term fire trends using multiple satellite datasets. We found that global burned area declined by 24.3 ± 8.8% over the past 18 years. The estimated decrease in burned area remained robust after adjusting for precipitation variability and was largest in savannas. Agricultural expansion and intensification were primary drivers of declining fire activity. Fewer and smaller fires reduced aerosol concentrations, modified vegetation structure, and increased the magnitude of the terrestrial carbon sink. Fire models were unable to reproduce the pattern and magnitude of observed declines, suggesting they may overestimate fire emissions in future projections. Using economic and demographic variables, we developed a conceptual model for predicting fire in human-dominated landscapes.

Full paper
 
For more information & research papers see GWPF coverage of wildfires

2) Solar Cycle 25 To Repeat Low Cycle 24, Scientists Predict
GWPF Observatory, 16 September 2020
 
Dr David Whitehouse, GWPF Science Editor
 
What a continuation of low solar activity would mean for global warming is something that will take a long time to judge.





 







The Sun has an interesting role in the debate about natural influences on global warming. Most climate scientists say its small change in radiance during its 11-year solar cycle – about one per cent – means that its effect is minor. Others point to the larger changes in UV than seen at optical wavelengths during a solar cycle as potentially significant, whilst many weather scientists maintain that solar activity is important on local scales.

Add to this the apparent coincidence that long-term modulation of the solar cycle such as the prolonged lower activity seen during the 17th century Maunder Minimum and the much briefer Sporer and Dalton minima, which may be associated with cooler climate on Earth, means that keeping an eye on decadal solar activity is important.

Solar Cycle activity has been lower during recent cycles so it is with interest that scientists note the recent start of Cycle 25 and make some predictions about how it might develop.

At a meeting yesterday of the Solar Cycle 25 Prediction Panel, co-chaired by NOAA and NASA, scientists said that Cycle 25 began in December 2019 with the appearance of small sunspots at high latitudes. According to Doug Biesecker of NOAA’s Space Weather Prediction Center Cycle 25 is expected to be similar to Cycle 24, which itself was somewhat weaker than average. The peak is expected in July 2025.
 
The status of predictions for Cycle 25 was detailed in GWPF Note 22 where it was reported that forecasts for the cycle’s length varied widely. With hindsight predictions for Cycle 24 were mixed. The number of sunspots at solar maximum was reasonably well envisaged but the timing of the maximum was wrong, possibly due to unusual disparities seen between the Sun’s northern and southern hemispheres.

Predictions about how Cycle 25 will unwind will be useful for planning for space weather – the solar influence on the environs of the Earth. What a continuation of low solar activity would mean for global warming is something that will take a long time to judge.
 
Feedback: david.whitehouse@thegwpf.com
 
3) Research Reveals “Climate-Complacency” Across Europe
University of Warwick, 14 September 2020
 
Most European citizens do not particularly care about climate change. That’s the striking finding from new research on the views of 70,000 randomly sampled European men and women.










Only 5% described themselves as “extremely worried” about climate change. The climate and the environment ranked only fifth in people’s overall views about priorities. There was also scepticism that co-ordinated action, for example to cut personal energy use, would make much difference.

“It seems there is a chance the current generation will be content to sell their great grandchildren down the river [sic],” said Andrew Oswald, Professor of Economics and Behavioural Science at the University of Warwick, and senior author of the study – Do Europeans Care about Climate Change? An Illustration of the Importance of Data on Human Feelings.

He also pointed out that so-called desirability bias, which is the tendency for interviewees to feel compelled to shade their answers towards ‘politically correct’ ones, might mean the true level of worry about climate change is lower than indicated in the statistical surveys.

The study has implications for economists and policymakers, Oswald explains. “There is little point in designing sophisticated economic policies for combatting climate change until voters feel that climate change is a deeply disturbing problem. Currently, those voters do not feel that.”
Professor Oswald and Mr Adam Nowakowski of Bocconi University in Italy analysed data from two large-scale sources, the 2016 European Social Survey and the 2019 Eurobarometer survey. They found:

* Europeans do not exhibit high levels of worry about climate change, with 1 in 20 describing themselves as ‘extremely worried’
 
* Europe’s citizens are more concerned with inward-looking issues seen as closer to home, such as inflation, the general economic situation, health and social security, and unemployment.
 
* Europeans do not have a strong belief that joint action by energy users will make a real difference to climate change.
 
* Women, young people, university graduates and city-dwellers show higher levels of concern about climate change.
 
*People living in warmer European countries had higher levels of concern than those in the cooler North of the continent.

Full story
 
4) Bjorn Lomborg: Sorry, Solar Panels Won’t Stop California’s Fires
New York Post, 14 September 2020
 
Putting up solar panels and using biofuels will be costly but do virtually nothing to fix the problem of wildfires.

The massive fires raging in California are being blamed squarely on climate change. Alongside ominous photographs of orange skies, the front page of the Sunday Los Angeles Times blared: “California’s Climate Apocalypse.” Golden State Gov. Gavin Newsom says the cause is climate change. Anyone who thinks differently, he insists, is in denial.

The governor is right that climate change is real, man-made and something we need to deal with smartly. But the claim that the fires are caused by climate change is grossly misleading. Translated into policy, it would steer the state to the worst way to help future Californians.

To understand why, it helps to know that California wildfires used to be much bigger. This past decade, California has seen an average burnt area of 775,000 acres. Before 1800, however, California typically saw between 4.4 and 11.9 million acres burn every year.

In other words, up to 12 percent of the entire area of the state — had its modern boundaries existed in the 18th century — burned every year. Old newspapers across the country were filled with descriptions of terrible fires. Back then, “skies were likely smoky much of the summer and fall in California,” as one academic paper noted. Elsewhere in the country in 1781, “the smoke was so dense that many persons thought the day of judgment had come,” The New York Times reported a century later.

This all changed after 1900, when fire suppression became the norm, and fire declined precipitously. In the last half of the 20th century, only about 250,000 acres burned annually.

But because most fires were stopped early, this left ever more unburnt fuel in the forests. According to one estimate, there is now five times more wood-fuel debris in Californian forests than before Europeans arrived.

Clearly, then, we used to have much more fire before global warming. Even this year’s record-breaking 2.3 million burnt acres is about half the lower end of a typical year in earlier times.

And the main reason we are now seeing more and bigger fires is because our century of fire suppression has left what researchers call a “fire deficit” — all the fuel that should have burnt but didn’t. It is now waiting to burn even hotter and fiercer.

Newsom is right that climate plays a part. It does create a more favorable fire environment by ­increasing hot and dry conditions. But experts estimate this plays a minor role. The much more important factor is the way we manage forest lands and develop our landscape.

When we keep suppressing fire, we ask for bigger and more terrible ­future fires. And we know how to fix this. We simply have to make many more prescribed burns that eliminate the built-up fuel. This is doable and smart. It would help reduce fire risks in just a few years. Unfortunately, it is also unpopular, because of ­increased smoke and risks from uncontrolled fires.

One prominent study published in Nature Sustainability this year estimated that California will have to burn about 20 percent of its area to get rid of all the excess fuel. But owing to popular opposition, legal challenges and regulatory limits, California manages prescribed burns for less than one-thousandth of that.

Instead of focusing on more prescribed burns, Newsom focuses on climate change as the overarching source of his state’s fires. He suggests that the answer is to speed up California’s transition to 100 percent renewable energy sources.

But any realistic climate solution will achieve next to nothing. A Californian change of policy will have virtually no impact on global climates. But even if the ­entire United States were to cut all its emissions tomorrow and for the rest of the century — an ­incredibly fanciful and enormously expensive assumption — temperatures would still climb, just 0.3°F less.

Fire would still get worse, only slightly less.

Californian fires are slowly coming back to their prehistoric state because of the enormous excess fuel load. Putting up solar panels and using biofuels will be costly but do virtually nothing to fix this problem. Prescribed burns will. What we choose depends on the information we get.
 
5) Michael Shellenberger: Forests That Survive Megafires Prove Good Management Trumps Climate Change
Forbes, 13 September 2020

Over the last few days, California Governor Gavin Newsom, other politicians, and the news media have pointed to climate change as the single most important cause of historic, high-intensity “megafires” ripping through California and Oregon. 

“This isn’t about ideology,” tweeted Governor Newsom, adding “What we are experiencing is an existential climate crisis.” 
 
But California’s leading forest scientists say that fire suppression and the accumulation of wood fuel, not climate change, are what’s made California’s fires more intense.

“Climate dries the [wood] fuels out and extends the fire season from 4-6 months to nearly year-round but it’s not the cause of the intensity of the fires,” said US Forest Service scientist Malcolm North. “The cause of that is fire suppression and the existing debt of wood fuel.”
 
And now a large, well-managed forest appears to have turned a high-intensity fire into a low-intensity one, proving that how forests are managed outweighs the higher temperatures and longer fire season caused by climate change.

“It ain’t over till it’s over but so far it looks as though [Southern California Edison (SCE) electric utility’s] decades of burning and selective cutting in its Shaver Lake forest has paid off, big time,” tweeted Jared Dahl Aldern, a forest historian, on Saturday. 

When the high-intensity Creek Fire arrived at the Shaver Lake forestlands it turned into what scientists call a low-intensity “surface fire,” which does not threaten the bigger and older trees. “The fire comes up to @SCE land,” tweeted Aldern, “drops to the ground, and stays out of the tree crowns.”

The Shaver Lake forest is not completely out of the woods yet because there are US Forest Service “in-holding” lands inside of Southern California Edison’s property. 

“I’m not worried about the fire on our property because it’s like a hot prescribed burn” said SCE forester Ryan Stewart. “But on the forest service lands it’s all fuel, and so if the fire gets in there you know it’s going to rage.”

But whatever happens to Shaver Lake, says University of California, Berkeley forest scientist Rob York, “There are lots of cases in the scientific literature of prescribed burns having changed fire behavior.”

Scientists point to several cases of high-intensity fires in the “crowns,” or tops, of trees becoming low-intensity fires as they spread from US Forest Service lands to National Park Service lands, which have been using prescribed burning for longer.

In 2013, after a high-intensity megafire known as the Rim Fire in the Stanislaus Forest reached Yosemite National Park, where prescriptive burning had occurred, it became a surface fire.

Similarly, the high-intensity Rough Fire of 2015 turned into a surface fire after it reached Sequoia National Park, whose managers had been using prescribed burns for decades.  

But the evidence for the efficacy of what foresters call “fuel treatment,” through selective logging, prescribed burning, or both, can also be found on US Forest Service lands.

In 2014, areas where there had been selective logging and prescribed burning survived the high-intensity King megafire Eldorado National Forest.

On a map of the fire “you can see a little green finger that juts out into the sea of red (100% mortality of trees),” said York. “This is an example of a shaded fuel break doing its job to modify fire behavior.”

Even so, other parts of the Eldorado National Forest that received fuel treatment still burned-up. 

The fuel treatment “really didn't make a big impact because it was so small relative of the size of the fire,” said York. “Mega-fires need mega-treatments.” 
York emailed me a photo of forest land where a “shaded fuel break” consisted of selectively-thinned forest surrounded on both sides by dense forest. “The strip of forest may change fire behavior in the treated area,” said York, “but not on either side.

“One may argue that the fuel break can allow crews to put out a fire, which is true in some cases,” he added. “But inevitably there will be a fire that the fuel break does not contain. 

“And after the fire we would have a strip of green forest, surrounded by blackened/charred forest on either side for miles,” notes York “I, and most in my field, would argue that the landscape on either side of the strip of thinned forest needs to look more like the strip in the middle.”
 
Similarly, the 2018 Carr fire burned through areas where there had been treatment of wood fuels over the last three decades. 

Even so, areas that had prescribed fire within the last five years, particularly the last three years, did better. 

Such cases are powerful evidence that selective logging and prescribed burning could allow many forests in California and elsewhere to survive climate change. 
 
Full post
 
6) And Finally: China Moves Away From Banning Petrol Cars
Bloomberg, 16 September 2020
 

China is poised to give fossil-fuel vehicles more time to co-exist with electric vehicles, moving away from considerations to have a deadline for a ban on conventional automobiles.
 
The country shouldn’t set a firm timetable for phasing out fossil-fuel vehicles, the head of a panel advising the government on the matter said at an industry event in Nanjing, China, on Wednesday. National conditions aren’t yet suitable for a target date, said the policymaker, Wang Binggang.

“We don’t want to kill fuel cars,” Wang said in a group interview. “Some countries have a policy banning fuel cars and we are against such moves.” He added that China will actively push the development of hybrid technologies to effectively save fuel and preserve coal reserves.

Wang said his panel’s recommendations will serve as the foundations for national policy. Chinese officials are drawing up plans for the auto industry for 2021 through 2035. Whatever determinations they make will impact local contenders as well as global giants from BMW to Tesla Inc. that have spent billions of dollars expanding in the world’s largest market.

China’s last roadmap on the auto industry was announced in 2017, when the government said new-energy vehicles -- all-electric, fuel-celled autos and plug-in hybrids -- would account for more than 20 percent of the country’s total car sales by 2025. Under the latest proposal, the NEV target for 2025 is 15 percent to 25 percent, Wang said.
 
For 2035, the NEV target will be 50 percent to 60 percent, Wang said, as the country looks to lead the world in the push away from internal-combustion engines.

After growing rapidly for several years, electric cars lost momentum in China in mid-2019 as the government moved to limit subsidies. Demand has picked up again in recent months despite the coronavirus pandemic and investors are showing an increased interest in EV companies. Tesla and Nio Inc. shares have surged this year, and Chinese contenders Li Auto Inc. and XPeng Inc. have had successful stock market debuts.

China will stick to its goal of electrifying the industry, yet there is a rising emphasis on gasoline-electric hybrids, Wang said. Such cars are an effective way to ensure all vehicles will be at least partially powered by electricity, he said.

see also: Banning The Sale Of Petrol Cars Would Be ‘A Colossal Error’


The London-based Global Warming Policy Forum is a world leading think tank on global warming policy issues. The GWPF newsletter is prepared by Director Dr Benny Peiser - for more information, please visit the website at www.thegwpf.com.

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