July 26, 2023

Huge Grass Fire in Eastern Washington: Was Drought or Climate Change a Factor?

A very large and fast-growing wildfire in eastern Washington burned through grass and range vegetation starting during the late afternoon of July 21st.   

Picture courtesy of Susan Stevenson

Called the Newell Road fire, the blaze expanded to roughly 60,000 acres just north of the Columbia Gorge east of The Dalles (see burn area below).


Some politicians and media outlets are claiming that this wildfire can be traced back to drought, which in turn was caused by climate change.   

For example, a Seattle Times today quotes Washington State Land Commissioner Hilary Franz:

“It’s really a testament to the drought conditions we’re experiencing as well as the fire danger"

followed by the article's author noting that:

 "The warm and dry conditions —exacerbated by climate change— are expected to continue through the summer. "

The facts are very clear that this fire had little to do with drought or climate change.  

It had everything to do with strong winds, human ignition, bountiful surface fuels, invasive grasses, and normal drying conditions.

Grass Fire 101

To get a big, fast-moving grass fire you need lots of dry, dead fuel (grass and range vegetation), strong winds, and an ignition source.

For the Newell Road fire, the ignition was clearly human-related, since there was no lightning during the days leading up to the fire.  Someone did something unfortunate.

Strong winds from the west built rapidly on the day of ignition, winds that were enhanced by COLD AIR moving into western Washington, thus increasing the cross-Cascades pressure difference.

The fire started in the Columbia River windy area.

There is a reason there are wind turbines all around the Newell Road wildfire area.  The NREF wind speed map (annual) shows the Newell Road wildfire area is particularly breezy.

Maximum winds on Friday (shown below) ranged from the mid-20s to 36 mph!   Quite windy.  


Winds came up rapidly that day...and cool air in western Washington was the key.  Again, cool air in western WA is not associated with climate change and flow out the Columbia Gorge from the west DECLINES during heat waves. 

So global warming had nothing to do with it.

Finally, there is the question of bountiful dry fuels that were ready to burn.

We start with the issue that much of eastern Washington, including the area in question, has been taken over by highly flammable invasive grasses, most importantly cheatgrass (a.k.a. grassoline).  

Here is an official government map of cheatgrass presence for non-Federal lands.  Wow...the area of the fire has extensive coverage of cheatgrass.



The influx of this highly flammable and densely growing grass is an important reason why wildfires are more frequent and intense east of the Cascade crest.  Global warming has nothing to do with it.

The grass was particularly bountiful over eastern Washington because last year was WETTER than normal over the region during the grass growth season and thus grass production was well higher than typical.  Spring 2022 was particularly wet and grass growth was substantial.

To illustrate, here is the spring/early summer (April 1-July 21) precipitation by year at Arlington, Or., located just across the Columbia from the fire.  Spring 2022 was the WETTEST year on record...and that contributed to a huge growth surge of grass.


What about drought this year near the fire?

Answer:  As shown by the plot above, THERE WASN'T ANY DROUGHT.  2023 was run-of-the-mill (near average) at this location--and certainly was not unusually dry.

So all the drought talk was without any basis.  

Because of all the precipitation-induced grass growth last year,  the USDA Fuelcast.net website had been advertising all spring the heavy fuel load present and the potential for fire.  



Just to repeat, drought and global warming do not produce bountiful grass loads like this.  USDA officials, such as the extraordinary rangeland expert Matt Reeves, have been warning about the great danger of major fires in the region for a while (you can watch his insightful "Reading the Tea Leaves" videos on the topic if you like.

Matt Reeves warned us

Finally, were the grasses unusually dry due to recent warm, dry conditions?

The answer is certainly no.  Let me prove this to you.

Grasses are known as 1-hr or 10-h fuels because they will dry out within 1-10 hr of drying conditions (no rain, sun). Winds promote rapid drying as well.  So it doesn't matter what happened in the weeks or months before...just a few hours of favorable weather and grass and range vegetation are ready to burn.

Every year, rapid drying occurs during mid-spring east of the Cascades and by mid-June the grasses have dried out and have dropped below the critical fuel moisture percentile (around 10-15%).

Below are the 10-hr fuel moisture values (again suitable for grasses) at the nearby Umatilla NWR RAWS site. Ready to burn (below 10%) by mid-May.  Hardly much drier in late July than early June.


What was the fuel moisture accompanying the excessively wet spring of 2022?  

Consistently ready to burn a little later (end of June).  But even in May that year there were periods of potential fire.

The bottom line in all this is that there is absolutely no reason to suggest drought or climate change had anything to do with the Turner Road fire of the past week, and it is disturbing the major local media (e.g., the Seattle Times) and key public officials are suggesting the opposite.

 














11 comments:

  1. This is a very informative post, loaded with good information. My recollection is that earlier this year your April 19 post was focused on spring conditions - conditions that would make for plentiful growth (including grasses) that might lead to wildfires. No doubt some harsh comments may start flowing in, but I think the writings have been very consistent. I hope that the agencies responsible for fire planning were paying attention.

    https://cliffmass.blogspot.com/2023/04/increased-wildfire-danger-over-western.html

    ReplyDelete
    Replies
    1. Here is what we can say for certain about fire planning for the dryland areas of Washington State, those areas largely covered with cheatgrass.

      Sooner or later, the cheatgrass will burn off. Three or four years later, it will be back as thick as ever. Eight or ten years after that, it will burn off again. Rinse and repeat.

      Delete
  2. Cliff I am glad you are acknowledging the recent trend in wet springs, producing good vegetation growth, followed by warm, dry summers as a factor in some of our large range and forest fires. I noted that this could be a factor in a comment I made to you a few years ago, but your response then was that there was no proof that recent springs were wetter. I think the precipitation graph for Arlington clearly shows this. Also, the graph of fuel moisture at Umatilla shows it was considerably drier this spring and early summer than last year with lower fuel moistures earlier this year and not recovering at night as well as last year.

    ReplyDelete
    Replies
    1. wxman... one or two wet springs does not make a trend. Mid-July of both years was dry enough to burn, with this year slightly drier...cliff

      Delete
  3. You did mention that this spring saw record rainfall, so I wonder if that, at least, has some potential exacerbation from climate change. I'm not familiar with the latest literature (I'm just an engineer who spent 4 years forecasting for the military), but my understanding is that global average warning will generally make wet areas wetter and dry areas drier. Taken with our invasive grass species and wet winter/dry summer Mediterranean-like climate, could we be looking at progressively worsening grass fire seasons from late spring to mid summer?

    ReplyDelete
    Replies
    1. Springs are getting modestly wetter in that region. Not huge (about .3 inch increase in spring over 50 years), but that could help slightly.

      Delete
  4. The cheatgrass invasion of eastern Washington, coupled with elevated CO2 levels, creates a feedback loop that exacerbates the problems of wildfires in our area. Cheatgrass was brought to North America in the late 1800's, likely from imported European seed crops. It quickly spread throughout the continent, finding footholds in cleared agricultural areas and range lands, pushing out native vegetation. It is especially adept at coming in after fires. Elevated CO2 levels can indirectly contribute to this problem by promoting the growth and proliferation of cheatgrass, making fuel loads more abundant and increasing the likelihood and intensity of wildfires. These elements go hand in hand. To say that man made climate change plays no role in grass fires is simply ignoring the plant's physiological response to high CO2 conditions.

    ReplyDelete
    Replies
    1. Most plant growth is enhanced by increasing CO2. But recent research (Blumenthal et al., 2016) suggests that cheatgrass is relatively unresponsive to increasing CO2. I would be interested in your evaluation of this and other supportive research.

      Delete
  5. Since I moved here over a decade ago, I've noticed that the area around Hood River and The Dalles almost always experiences a substantial burn around this time of year, as well as in the late Summer and early Fall months. Long - time residents are used to it, the question becomes why isn't the MSM?

    ReplyDelete
  6. " taken over by highly flammable invasive grasses, most importantly cheatgrass" BINGO!

    If someone finds a way of wiping out cheat {Bromus tectorum} I would be happy to contribute to that person's retirement fund. They would also win a Noble Prize.
    I wonder if Land Commissioner Hilary has walked through a patch of cheat? Send her over my way and I'll give her a lesson. Even serve a glass of wine while she picks the schist out of her socks and shoelaces. :)
    Some info and photos by someone (?):
    https://sageecosci.blogspot.com/2012/12/have-cheatgrass-beer-and-help-great.html

    ReplyDelete
  7. Research scientists at Washington State University have been looking at ways to control cheatgrass for more than forty years. Their methods work for small plots of land, but haven't yet been successful on the larger rangelands.

    A basic problem with cheatgrass is that it greens early in its growing cycle and then dries out to become fuel for fast-moving rangeland fires. Here is a question for consideration: What new and innovative ways funded by federal dollars might be used to deal with the problem?

    For example, could the scientists at WSU create a genetically modified grasshopper which likes cheatgrass? The idea would be to let billions of these grasshoppers loose on the region's rangelands early in the spring while the cheatgrass is still in its maturing stage, well before it can dry out.

    One problem with this approach might be that the maturation cycle of a standard issue grasshopper isn't in sync with the maturation cycle of cheatgrass. The grasshoppers wouldn't be big enough early enough in the spring season to eat as much green cheatgrass as is needed.

    Not to worry. With enough federal dollars, it might be possible to use genome modeling of grasshopper DNA to create a weather-resistant, early-maturing super-grasshopper which likes cheatgrass more than it likes other kinds of grasses or commercially grown crops.

    Once the cheatgrass growing season is over and the cheatgrass crop is largely consumed, what do we do with these many billions of fat grasshoppers? Might these be harvested in order to obtain many thousands of tons of protein matter suitable for conversion into insect based food products?

    This would be an exceptionally ambitious vision for the future of our Washington drylands. But what if our grasshopper harvesting scheme doesn't work very well and these many billions of grasshoppers turn their attention to our commercial crops? How could we deal with this problem, should it occur?

    As a risk management tool for keeping our cheatgrass eating grasshoppers in check, we might think about having WSU work with the University of Utah in developing a special breed of seagull which prefers our DNA engineered grasshoppers to any other kinds of insects it might eat. Millions of fat seagulls might even become a substitute of sorts for chicken.

    Who knows, with enough creative thinking supported by enough federal dollars spent by the billions over the next three decades, it might be possible to completely transform our cheatgrass-covered fire-prone Washington drylands into a mighty source of sustainable agriculture for the nation; and, possibly, for the entire world.

    ReplyDelete

Please make sure your comments are civil. Name calling and personal attacks are not appropriate.