August 17, 2018

Air Quality if Far Better in Western WA But Smoke Will Return

Take a deep breath.  It's ok.

Air quality has greatly improved at low levels over western Washington as cool, clean marine air has pushed in at low levels.   You can see this with a plot of the concentration of small particles in the air (PM2.5), the kind that can move deep into your lungs (see below for Seattle-blue color, Bellingham-red color, and Tacoma-yellow)

From the Puget Sound Clean Air Agency Website
Our air is by no mean pristine, with more particles than normal, but Seattle and Tacoma are at levels about 1/10th as high as Wednesday.  Bellingham is better, but they are closer to the BC fires and getting hit by some smoke this AM (but still down).

The excellent NOAA/NWS HRRR smoke model is predicting improving air quality at the surface during the next 24-h, something made clear by comparing the forecasts between 5 AM today (Friday) and tomorrow (see below, red is bad air, improving towards green, blue, and white).  Worse but still improving over the eastern slopes of the Cacades.

So Saturday's air quality should be decent as well. 

But then things change.  Upper-level high pressure builds in along the BC coast, coupled with a low-level trough of low pressure moving northward into western WA.  As a result, we will develop easterly and northeasterly flow in the lower atmosphere, bringing smoke back into the region.  This is well illustrated by the forecast winds and temperatures at 850 hPa (about 5000 ft) for Monday morning at 2 AM:

The NASA GEOS-5 model shows plenty of smoke blowing south over us on Monday at 10 AM (see map)

So enjoy the clean air, things will degrade by Monday.


  1. I find it interesting we don't hear how our upwind neighbors are managing their land, when it clearly affects us (pardon the pun).

    UW alum Ze'ev Gedalof explains some of the possible effects of the loss of biodiversity due to wildfire suppression. There's also other research that quantifies the loss of biodiversity in "managed" (e.g. logged) forests. And BC's forests have been some of the most aggressively logged in the world.

    A factor not discussed in these articles is the change in moisture retention of forests due to loss of biodiversity, particularly during fire seasons.

    Moisture retention impacts of biodiversity loss have been studied, and certain mechanisms like "laddering" of fire from understory to overstory have been studied - what I haven't seen studied is the quenching effect of native levels of biodiverse understory on fire and fire temperatures.

    The quenching mechanisms of high-moisture plants has been well documented as it relates to landscaping and protection of structures from wildfires.

    So it would be interesting to know how many of the native species of understory are fire-quenching - i.e. high moisture content.

    It would seem reasonable to surmise the loss of biodiversity from 150 years of fire suppression + historic and current logging practices could be a SIGNIFICANT contributor to the nature of recent wildfires.

  2. Cliff, I invite you to present graphs comparing rainfall in recent summers to that of summers past. It really seems to me that the summers have become a lot drier since about the turn of the century. Thinking back to the 70's and 80's, it seems like about 1 in 3 or 4 of my hikes and climbs got rained out even in July and August. No more- but we are paying a high price. How much drier have our summers actually gotten? Perhaps you could compare rainfall for each month (say, May, June, July, August, and September) for the last 30-50 years, and overall summer rainfall. I am talking about rainfall in western Washington, but also for the Cascades.

  3. What about the coast? Will that be saturated with unhealthy air as well? Thanks.

  4. We need a REAL fleet of water-drop tanker planes. It's impractical to put boots on the ground on those high mountain tops where lightning starts many of these fires. Has anyone calculated the true and total cost of all these wildfires? If this was a terrorist attack I'll bet the response would be different. I'm mad as hell that another summer is smoked out. The one and only 747 water tanker IN THE WORLD is overseas again while we get poisoned here in America and a years worth of carbon is released in just 2 months. Doesn't anyone care?

  5. Cliff, since horrible air quality seems like a thing we will be contending with for the foreseeable future, could you recommend both an indoor and outdoor air quality monitor that measure PM 2.5 for personal use? I would like to see what our neighborhood measures and how well we are filtering house air (people in the house have asthma). Thanks in advance!!

  6. Idea for a future post: I'd be interested in understanding the smoke levels of the last two summers in historical context. I've lived in the PNW since 1994 and can't remember any *summertime* conditions as bad as we've recently experienced. How do the recent summers compare historically? Also, to what extent can we assign the cause to human caused climate change? Thanks!

  7. Maybe we should make asphalt from captured carbon and pave the forests with it, thus eliminating any chance of excess emissions from fires in the future whilst simultaneously removing CO2 from the atmosphere.

    We could level nearby mountains and use the aggregate to make the asphalt lighter colored to reflect more heat into the atmosphere, cooling the planet further.

    To account from the CO2 capture loss from growing trees, we could install thousands of power turbines in the asphalt that generate electricity to power carbon sequestering devices to create more and more of this "green asphalt" from captured CO2.

    And there shouldn't be much danger of birds being slaughtered by the turbines, as the asphalt landscape won't really provide any shelter or sustenance for fowl.

    To account for the loss of heat-reflecting particulate from wildfires we could create mile-high smokestacks devices to loft dust from the crushed mountains at extreme velocity high into the atmosphere.

    Then we can really feel like we are controlling the environment more effectively and get us back on track to the correct temperature.

    1. Nice tongue and cheek discussion about leveling the planet to control global warming & associated impacts.
      Stanford Univ, et al, reported in 2009 that Bioenergy Carbon Capture & Storage (BECCS) and/or biochar can effectively remove CO2 from the earth's atmosphere, especially if it became a priority like the "Manhattan Project"

  8. M&M - check out the AirVisual app on your phone

  9. M&M... . They sell a decent dual sensor equivalent of a PWS for about $300. Designed to upload to their system and display on the map link above. You can see their sensors all over the world in real time on their map

  10. Cliff,

    I would also like to see a post on Oregon and Washington wildfires and summertime smoky airs in a historical context, like you've provided for California. How many acres have burned in these states for past years; summertime rainfall, plus smoky conditions. I keep hearing from various news sources that what we're experiencing is the New Normal and we should expect it to continue and get worse.

    I moved here in 1996 and never saw conditions like this until the last two summers. This is enough to make me want to move to the Eastern US. The Western US seems to be becoming uninhabitable. It's not healthy to be exposed to conditions like this. I would like to hear your opinion plus the historical charts about if this is due to global warming (which means things'll get worse) or other factors such as forest management practices or more people which are more controllable. I'm seriously ready to move, so I eagerly wait to hear from you on this.

  11. @Jenerous and @Cliff, the AirVisual app you mentioned is currently (as I post this) forecasting an AQI of 201-300 for Monday, Tuesday in the Seattle area. This is *worse* than last week where it peaked at around 175 or so. Is this true, or is AirVisual's forecasting inaccurate?

  12. Once air gets worse by Monday, how long will it stay bad. We are scheduled to be on Lummi Island next weekend and I am trying to get a sense of how bad it will be.

  13. Unknown-

    You should just move. The western US is becoming uninhabitable? Really? Because of a couple weeks of smoke each year? Wow, that's not an over-reaction or anything. Hopefully a lot more people think like you, we have way too many people here now as it is.

  14. It always takes one of these occurrences to bring out the shrieking hysterics. Want to know what seriously bad air quality is like? Try living around the steel mills of Gary Indiana in the 60's and early 70's, when there were no pollution controls and the ovens were going full blast. Or LA during their many choking days before cars had catalytic converters and used lead gas. We used to be a much hardier breed.


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

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