Reposted from the Cliff Mass Weather Blog
Tuesday, October 6, 2020
The wildfire season has now ended in Washington State, with no major fires currently burning and a very wet weather system approaching for the weekend.
Although the first half of the fire season had below normal acreage burned, we ended up with more fires and more burned acreage than normal (see WA DNR statistics below).
Global warming? Or is something else going on?
Some politicians and media outlets are claiming that global warming was the explanation, but as we shall see, something else was going on: COVID-inspired trash burning and the extraordinary dominance of grass fires over forest fires.
Let’s begin by looking at a map of this summer’s wildfires over the state (see below). There were some big fire areas in eastern Washington. But look carefully and you will notice something important: nearly all the acreage burned was not in terrain or in forests, but in the grasslands and scrub of the eastern Washington lowlands.
If you wanted a clearer view of this situation, here is a recent MODIS satellite image centered on the Columbia Basin in which the burned areas are indicated by red. You can see the agricultural areas (light green) and forested areas (darker green).
We can compare the fires this year, with the fires of the past 20 years (see below), many of which have been on the eastern Cascade slopes and the slopes of the Okanagan and Blue Mountains. But not this year.
As I noted in earlier blogs, 2020 was not a particularly favorable year for higher-elevation wildfires, with normal April 1 snowpack and temperature/precipitation conditions that were not particularly unusual.
But this year, something did happen that made the grass/sageland burn. Something unusual.
Extraordinary, record-breaking winds (for the season) hit eastern Washington, with gusts reaching 50-70 mph on September 7th.
These winds both helped initiate grass fires, for example from failing, sparking powerlines, and caused the rapid growth and spread of the grass/sagebrush/brush fires.
The grass was already dry enough to burn after a normal, hot dry summer in eastern Washington. And even if it were WET, a few hours of strong winds would have ensured it was dry enough to burn.
A plot of the ten-hour fuel moisture at the Columbia NWR RAWS fire weather site in central Columbia Basin (below) for the 60 days ending Sept 8 shows the story. Then ten-hour fuel moisture is for vegetation of 1/4 to 1 inch in diameter and values under 15% are dry enough to burn. As you can see, the 10-h fuels were dry enough to burn all summer (below 10%). Grasses (one-hour fuels) would have been even drier. The same thing would be true of summers of other years (I checked).
The area near site and location are shown below:
Summer grass fires like this have NOTHING to do with climate change.
A normal summer makes these fuels dry enough to burn. Increasing temperatures are irrelevant, and global warming models do not show much change in precipitation (and even if it got drier it would not make a difference). The temperature and precipitation today are sufficient for fires.
The key issue in this event was the strong winds, which were accompanied by COLDER THAN NORMAL temperatures. The crazy powerful winds were forced by a cold, high pressure areas to the east and such cold highs should become LESS frequent under global warming.
And there is something else. Unirrigated areas in eastern Washington are much more flammable today than a century ago because of the invasion of highly flammable invasive grasses such as Cheatgrass (a.k.a. grassoline)–check the map below to see this.
It is totally frustrating that certain politicians, some local newspapers, and some environmental activist groups are pushing an inaccurate claim, not supported by any scientific evidence, that the eastern Washington wildfire siege of September 7-8 was the result of global warming. It is simply not true.
Such false claims not only promote unnecessary fear and concern but work against taking steps that would actually help mitigate future future fires.
For example, when very strong winds are forecast (and they were), eastern WA utilities could de-energize the power lines, as done in California. Homes in the middle of grassland/brush could be built or remodeled to lesson their tendency to burn. And grass/brush/flammables could be cleared away around buildings to create a safe space.
As I mentioned above, Washington State had more fires than normal. The cause was not global warming, but COVID-19.
Many of the fires this year were debris fires that got out of hand. Folks, forced to stay home because of COVID ,decided to clean up their properties and then burned the debris. To quote from Hillary Franz, Commissioner of Public Lands:
“Everybody is following the ‘stay home, stay safe’ order. They’re getting more time at home to do yard work. We’re seeing an unprecedented number of debris piles, and we’re seeing an unprecedented number of people that are lighting those piles on fire”
In contrast, to grass fires, global warming may well increase the risk for forest fires in some areas over the course of the century. But there are a number of other factors that play a role in the long-term trend in forest fires, including fire suppression over the past century, poor forest practices, human ignition of fires, invasive grasses and plants, and people moving into wildland areas. It’s complicated.
This is the kind of blog that gets me into trouble with the climate activist community, but folks in our state deserve the truth and only the truth will allow society to take rational steps to protect itself from environmental threats.
After blogs like this, activist groups like 350Seattle typically call me names (denier, etc) and previously pushed KNKX to kick me off the radio. Well, they succeeded at KNKX but at least I have this blog and the support of many of you. ___________________________________________My blog on KNKX and the Undermining of American Freedom is found here.
An extraordinary story about Matt Martinez, Program Director of KNKX, is found here. All KNKX listeners should read it.__________________