Reposted from the Cliff Mass Weather Blog

If the nation and world are going to deal with climate change, it is essential that the public is given accurate information.

Unfortunately, a number of media outlets (e.g., the Seattle Times and NPR), politicians, and activist groups are consistently distorting the truth.   There are few better examples of this problematic behavior than claims that the wildfire that destroyed the eastern Washington town of Malden in September 2020 was the result of climate change.

This blog will provide you with facts based on data, peer-reviewed papers, and government reports.  You can decide whether some folks are misinforming you.


The Claims

During the past year, a number of media outlets, politicians, and climate activist groups have made unfounded claims that the Malden/Babb fire, which destroyed the town of Malden (roughly 30 miles south of Spokane) was the result of human-induced global warming.

For example, last week the Seattle Times did a long story on the Malden fire and concluded.


National Public Radio, including local NPR station KNKX, did a story with the suggestion that the fires were the result of “global warming hitting us hard.”

And then there is our governor, who claimed the Malden conflagration was a “climate fire”


“ I think we need to start thinking about this as a climate fire because that’s what makes them so explosive.”

I could give you a dozen other examples of such claims about the Malden Fire and climate. 

 These claims are unfounded and this blog will provide you with the facts.  

The Malden/Babb Fire Event

The Malden fire ignited around noon on September 7, 2020, was long and narrow, and moved within hours from its ignition point southwestward across the towns of Malden and Pine City (see map).

Fact 1:  The Malden Fire was a grass and bush fire.  Trees did not supply significant fuel.

The route of the fire, in arid eastern Washington. was nearly entirely grass, wheat fields, and small bushes.   Isolated trees were not a significant fuel source of the fire and most of them remained green after the fires.  A satellite image of the path is shown below (GoogleEarth Pro).


An image from GoogleMaps from PineCity/Malden Road gives you a first-hand view of the kind of vegetation the fire traversed.

Grasses and small diameter fuels are easily ignited, dry quickly, and can produce flashy, fast-moving fires when there are strong winds:  ALL of these factors were elements of the Malden fire.

Fact 2:  The fire was started by a tree, blown by strong winds, hitting a transmission line, creating sparks that ignited grass below.  

This was the conclusion of the official WA State Department of Natural Resources report.  An image of the tree and the power line is shown below.   Note that the tree is STILL GREEN.  Stunningly, DNR found that that tree had hit the powerline before, with multiple scars on the tree branch that caused the fire.

Fact 3:  Unusually strong winds played a critical role in the fire
Not only did the winds start the fire, but winds rapidly drove the fire to the southwest.  The strong winds, which were very dry, further dryed the surface fuels and provided lots of oxygen for fire growth.
The winds that day around Malden were extraordinary in strength, with gusts from the north to northeast reaching 30-50 mph, something indicated by the winds at the nearby Escure RAWS station, about 25 miles downwind of Malden (see below).


Climatological data suggested that the low-level northeasterly winds that day were extremely unusual, if not unprecedented.  Support for this statement is found in a peer-reviewed paper I wrote with others that was accepted in the American Meteorological Society journal Weather and Forecasting.
Why Global Warming/Climate Change Had No Role in the Malden Fire
This is easy to demonstrate.  
The grasses and other light fuels around Malden are always dry enough to burn by mid-summer.  This has always been true and has nothing to do with climate change.  Eastern Washington has warm, dry summers and seasonal grasses dry out each warm season. 
Below are the 10-h dead fuel moisture (small diameter fuels than can dry within 10 hours) for summers of 2020 and ten years ago (2011).  The fuel moisture dries out over the summer to under 10%.


And my peer-reviewed paper  documents that the 10-h dead fuel moisture was NOT unusual right before the event (graphic from the paper below showing Columbia Basin fuel moisture conditions).  Very typical.


Fire danger from light fuels is greatly reduced when the 10-h dead fuel moisture is above 20%, but there is great danger below 10%, which was evident in September 2020 and is typical for late summer.  
Once you are dry enough to burn readily, you are dry enough to burn.  A bit warmer or drier conditions during the normally hot/dry eastern WA summers will have little impact.  A real weakness of the global warming arguments.
But there is more.   Light fuels, like grasses, dry very quickly under dry, windy conditions.  That is why grasses and small bushes are called 1-h and 10-h fuels.   The Malden fire was preceded by exceptionally strong dry winds.    


So even if the fuels had been wet before the event, they would have become sufficiently dry to burn due to the strong winds that day. The preceding weather and climate conditions were not relevant.
Even More Reasons Why Global Warming Had Nothing to Do with the Walden Fire
The extraordinary strong, dry northeasterly winds were key for initiating and spreading the Malden fire. And such winds will dry light fuels even if they were wet before
It turns out that global warming/climate change will probably WEAKEN such strong offshore-directed winds, because the strong winds during late summer/early fall are generally associated with COLD high pressure in the interior, and global warming preferentially warms the interior of the continent.  Such warming weakens the high pressure and thus lessening the strong northeasterly winds.  I have been working on this issue, with funding from the Amazon Catalyst project and NSF (see graphic below)
Climate models also suggest the potential for more convective showers in eastern Washington under global warming.
So global warming/climate change may lessen the chances for such fires, NOT increase them.  You won’t read that in the Seattle Times.

Regional Climate Simulations Indicate Weakening Easterly Winds over the Region Under Global Warming

The Bottom Line
Major media like the Seattle Times and National Public Radio, as well as some local politicians, have claimed that the Malden Fire was caused by or made more likely by global warming/climate change.  
This is not true and they are doing substantial damage by blaming global warming and not calling for taking concrete steps to ensure that Malden disasters don’t happen again.
The Malden Disaster Was Preventable
Instead of blaming global warming/climate change, there are concrete steps that could have prevented this tragedy.
First, trees near powerlines need to be trimmed so branches don’t touch or fall on energized circuits.  Clearly, this was not done for this case.   Considering the limited trees of the region, it should not be hard to do so.  Furthermore, if the powerlines are not properly maintained, at least depower the lines during the very limited periods of strong winds.   The winds were well predicted ahead of time for this event.

Courtesy, First Energy Corp
Second, homeowners must create defensible spaces around their homes, without vegetation and debris.  Using google maps, one can view the conditions around the homes in Malden before the disaster.  Many, if not most, had no defensible space, with vegetation and grass immediately around the homes.  And homes can be built to better withstand fires, including non-flammable roofs, screens to prevent embers from entering roof spaces, and more.

Malden before the fire.
A Plea.
Please no name-calling.  Every time I write blogs like this on climate change,  I get angry messages from activists, calling me a slew of names, with accusations that I am receiving funding from oil companies (I am not), and worse.  The Seattle Times did a hit piece on me in August in reaction to my blogs about the heatwave and my criticism of their continual transition to advocacy journalism.  And activist scientists like Michael Mann and Gavin Schmidt make nasty tweets.
I am as concerned about global warming as any rational person, but we need to start with facts and not hype and exaggeration.
If you are unhappy with the blog, TELL ME WHAT I HAVE GOTTEN WRONG TECHNICALLY.

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September 13, 2021