Tuesday, September 15, 2020

Where's the smoke coming from now?

One key thing that we need to get smoke out of the air is to stop putting smoke into the air. So where is the smoke coming from now? Here in Washington we have some active fires although the map of Washington below is somewhat misleading as only a few of the fires shown are producing significant amounts of smoke. Three fires in the state were listed as showing moderate fire behavior today including the Big Hollow, the Inchelium Complex, and the Cold Springs fires. The others including Whitney, Fish, Apple Acres, Pearl Hill, Sumner Grade, Customs Road, Babb, Manning Road, and Evans Canyon are listed with minimal fire behavior so they are not smoke free but are unlikely to be making significant contributions to our impaired air quality outside their local area.

But to the south in Oregon there are numerous very large fires that are actively burning and sending smoke north to Washington. The northern group of fires including Riverside, Beachie Creek, and Lionshead, plus a few small ones nearby have a combined size of nearly 500,000 acres and are burning in heavy timber, slash, and brush fuel types. But that’s not all, numerous other large fires stretch the length of the Oregon Cascades and into California. Recent wind conditions have been moving smoke from these fires to the north and right towards us. The smoke layer has actually resulted in cooling many of the fires somewhat although as the smoke begins to thin out somewhat the fires are expected to become more active. More smoke, less fire, less smoke, more fire? It sounds like an unfortunate cycle. 


But on the horizon, arriving Thursday and lasting until Saturday, there is a prediction for enough rain in the Oregon Cascades to tamp these fires down considerably. Will they go out? No. And the farther south in Oregon you go, the less the rain will result in significant suppression of the fires. But the hard work of the firefighters combined with an assist from the weather gods should result in a pretty decent reduction in smoke production by later this week. Let’s hope so!


55 comments:

  1. thank you all for all this hard work!!! reading your blog religiously right now and eagerly awaiting the clean air. love the detailed explanations!

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  2. So, it’s not even the smoke from WA fires that’s making WA air horrible...
    Considering some guy was arrested TWICE in the same day in OR (Yes, that means he was released the same day just to start ANOTHER fire) that is infuriating to me. Even if the small fires he set are the only case of arson, there needs to be a MUCH greater penalty for accidentally starting a wildfire, and for even doing reckless things during periods when there is extreme fire danger,

    It’s one thing when lightning starts fires, or even downed powerlines from high winds- acts of God. Unavoidable.
    People leaving campfires? Burning trash? Dragging chains while driving? Throwing a lit cigarette out the window? Makes me infuriated. And those people can’t be charged with arson because it’s “accidental” no matter how stupid they were acting.

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    1. Arson and accidentally starting a fire are both lousy and society should (and to some degree does) take proactive measures to curb them. However, the air quality issue isn't just about poor individual choices. The west coast is more of a tinderbox than it used to be (https://fivethirtyeight.com/features/the-west-is-burning-and-climate-change-is-partly-to-blame/). So, leaving human behavior constant, we're going to see more fires and bigger fires.

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    2. I really think this leads into a deeper question of how our culture has normalized the use of fire and we are desensitized to its danger... compared to past cultures that were much more reverent of its power. Dry fuels and high winds are extremely dangerous but not sure if the average person thinks about it. We have routine safety drills for earthquakes, building fires, etc. in the event that they occur. Outdoor fire safety needs to be more routinely highlighted.

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    3. ThanksJanice - say I just heard from a colleague that another blanket of smoke is approaching Western WA from Oregon, and we should lower expectations for the date we will be breathing clean air again.... Can you validate this?
      Thank you for your service - government jobs are important jobs.

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    4. I don't think there's a blanket of smoke about to lay over W. WA but there's certainly still smoke coming up from the major fires in northern Oregon. Although most of it seems to be hitting the Portland/Vancouver area and the traveling out the Columbia Gorge to eastern WA.

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  3. Thanks for the great information, keep up the great work!!

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  4. How exactly is the WAQA index calculated? I found the details on AQI here:
    https://www3.epa.gov/airnow/aqi-technical-assistance-document-sept2018.pdf
    but haven't been able to find anything for the WAQA index.

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    1. There are sources online that show the comparison of AQI and WAQA, but they are outdated now. Here are the current breakpoints (going from good to hazardous) for WAQA in micrograms per cubic meter: 12, 20, 35, 80, 150. For AQI they are: 12, 35, 55, 150, 250.

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    2. but how is WAQA actually calculated using the concentrations of the various pollutants (O3, PM2.5, PM10, CO, NO2, etc)?

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    3. Usually a site only has one pollutant monitored, but if more than one is measured, whichever is worse on the WAQA scale gets shown on the map. WAQA is calculated the same as AQI, except the breakpoints are different for PM2.5 (stated in the previous comment). You can see the AQI equation here: https://forum.airnowtech.org/t/the-aqi-equation/169 and you can see an AQI calculator here: https://cfpub.epa.gov/airnow/index.cfm?action=airnow.calculator

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    4. You can also see the current AQI breakpoints for all pollutants here: https://aqs.epa.gov/aqsweb/documents/codetables/aqi_breakpoints.html

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    5. So it seems like WAQA makes a much more cautious approach than AQI? If I am interpreting this correctly, then a concentration of 150 micrograms (or more) per cubic meter is considered "hazardous" on the WAQA scale, but only be considered "very unhealthy" on the AQI scale?

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  5. So... what's the lookout for the weekend? I watched the Seahawks this last Sunday and thought, "it's a good thing this wasn't a home game!"

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    1. Predicting wildfire smoke more than a few days in advance is difficult. Right now I'd like to say the outlook is really good for cleaner air. We've got a system forecast to move through on Friday. Coastal sites are starting to see moderate improvements, indicating cleaner air over the Pacific. Forecasts predict westerly and southerly winds bringing that "cleaner" marine air over us starting tomorrow. Here comes the great big but...

      The system might produce some thunderstorms, fires are still burning, new fires can start. Southerly winds can still carry smoke from Oregon and California into WA. So the positive outlook is also relying on a reduced input of smoke into the system and that is much, much more difficult to predict than wind and rain.

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  6. Thank you for all this info. I like to know the details and you provide much more than the news weather media. Appreciate the work you do.

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  7. Roughly how fast does smoke travel? I.e. the smoke that's bugging me here in Seattle, is it coming from fire in Oregon that was burning earlier today, yesterday, or last week?

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    1. When all that smoke from WA, OR & CA fires pooled off the coast last week, mixed together a little and slowly started coming back at us this week, it is very hard to say whose smoke made it into which part of the reservoir. Winds are turning south now and this means a little fresh smoke from OR fires will be coming our way, as well. It is all driven by wind movement at different levels, and their complex interplay.

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  8. thanks for all the information and insight. I appreciate the efforts you put in to explain what's going on. hoping that I'll be able to breathe again on Friday...

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  9. I'm wondering if you can give us a sense of scale for these sizeable fires ? Hazardous,5xx level, we've had for almost a week now is one thing. If we get to healthy this weekend and oscillate between red/purple and green we can handle that. Are we talking that kind of back and forth, or hazardous on/off like this week has been or unknown?

    Thanks again 👍

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    1. You don't say where you're located but I believe most areas of the state are at the early stages of improving air quality conditions. The exception is areas close to active fires, Colville, Spokane, and Omak for example. And at the moment the smoke from Oregon is traveling through the Columbia River Gorge and into parts of central and eastern Washington so Hood River to Yakima to Walla Walla areas will be slower to clear. But in general I think we're at the beginning of the end of this event. Hang in there another day or two and we should be able to say goodbye to Hazardous and Very Unhealthy air at least.

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    2. Janice,

      Sorry! In Vancouver WA next to the biggest fire in OR and one of the biggest in WA.

      So I'm wondering if the amount of smoke could happen again that led to sustained 5xx level AQ? These major fires all burned in OR / WA around the same time running tens of miles in single days/nights over the first weekend. While still active, are they large enough to generate similar amounts of smoke the could again cause hazardous air levels? And if conditions line up just right, sustained hazardous levels?

      Thank you for your diligence especially knowing you are going through this just like we are.

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    3. Ah yes, Vancouver area is likely to be in the same "close to active fires" category. But overall I believe the fires are getting a little smaller and the big pool of smoke is thinning so I don't think you'll see 500+ levels again. You may want to check out the forecast from an "Air Resource Advisor" assigned to some of the fires in Oregon. She's forecasting air quality for Portland and describing the situation on fires in the N. Oregon Cascades. https://wildlandfiresmoke.net/outlooks/nworegon

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  10. Are you saying this replaces the current 50/100/150 system? I know our air standards were outdated so that makes sense.

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    1. Seems you are replying to the WAQA thread. If I understand your question, no, the index stays the same... but sometimes the breakpoints for converting from mass concentration to index changes.

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  11. Thank you once again for this excellent blog. Do you think we need to prepare for episodes like this to happen into October and beyond, as California's wildfire season has not even peaked? I think our rain would normally prevent this, but all bets seem off right now. Thanks!

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    1. A lot of things have to come together for an event like this. Fall is generally an active weather season for us, so it is not normal to have these inversions over the whole state tapping in to a pool of smoke sitting at a low enough elevation and leaking slowly.

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    2. this blog is so helpful. Thank you for your hard work and clear communication.

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  12. I imagine that combining the complexity of the fluid dynamics problems of smoke modeling with the uncertainty of firefighting would make for very low confidence predictions. But putting it in this way helps us understand the context and intuitively get a sense of the range of possible outcomes for the near- to mid-term. Thanks for including this info!

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  13. Darrington has appeared to be relatively clean for the past ~20 hours. While the areas to the West and South have remained bad. What would explain this behavior? Where is the clean air coming from? Does a low pressure system moving in at the surface level pull the clean air down from above the smoke?

    Also, now that the smoke has had time to settle into most areas of the state. Are heavily wooded areas likely to be cleaner or less clean than less dense or open areas? Does the forest filter the smoke or hold onto it?

    Thanks!

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    1. Darrington wasn’t running as high as other sites in the heart of the Cascades even before the slight improvement in ventilation caused by the weather system that blew by yesterday. All sites in the Cascades did record a drop early afternoon yesterday. Since Darrington wasn’t starting out on the top step, they ended up one rung below the rest. Other PurpleAir monitors in the region also exhibit the same trend.

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    2. With the caveat that they are relatively inexpensive, consumer oriented sensors, would you say that the PurpleAir PA-II sensor is one of the more accurate devices that the public could use to measure outdoor and indoor air quality at their home?

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    3. Hi Nick, Not to sound like an annoying scientist, but typically we find the Purple Air sensors are very precise, but not very accurate. What I mean by that is if you compare PurpleAir data to an 'official' PM2.5 monitor, they are highly correlated, but the PurpleAirs tend to report PM2.5 concentrations about twice as high. EPA has created a site fire.airnow.gov that reports both the permanent agency monitors and the PA sensor data with a correction algorithm applied so they are more accurate when compared to advanced analyzers. Purple Air's map also offers the option of applying a correction and the LRAPA correction is similar to the one used by EPA.

      Now to answer your actual question: I'm not sure they are the most accurate, but they have been well characterized by several different research groups and they are certainly one of the most popular out there.

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    4. Thank you very much for the reply, Odelle, and being a big fan of science, didn't find it annoying at all!

      Both precision -and- accuracy would be ideal, but as you mention a correction algorithm is available which can hopefully provide more accurate data, I think I'll pick one up when they're available. I had been curious what the LRAPA correction on the PurpleAir meant, so thanks for your very detailed answer!

      The work you and your colleagues do, and your interaction with the public on this blog, is very much appreciated -- thank you!

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  14. Question about different AQI readings. I've got a bunch of links to air quality websites, and I'm wondering why there's been a big difference between the US AirNow readings (where Olympia is currently 176) and the WA ecology one which is higher (now 238), but over the past week the difference has been about 100. I'm assuming they're calculated differently, but I don't see the details. Is one more "trustworthy" than the other? Thanks for all you do!

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    1. Eriksven, yes there are two different formulae and this is an ongoing source of confusion for the public. Both use the same underlying mass concentrations but ECY uses a more conservative set of breakpoints (i.e. paints a bleaker picture so you can take protective steps earlier).

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    2. But even if the scales that interpret the readings have different breakpoints, surely those breakpoints don't have anything to do with the (frequently) triple-digit spread between the actual numerical readings themselves, right?

      (Like others here, I've been passing your fantastic info on this site to a wide range of family/friends who can't be bothered to do the reading themselves. :| But this question has come up a couple times and I haven't seen it addressed, yet... And thanks, again, for everything; this blog was awesome the last time I said so, back in 2018, and it's even better today!)

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  15. The hardest part besides living in a closed up house for so long is trying to sift through all of the information about which portable air purifier I should buy for smoky conditions. I have looked at the links previously given, but find it all confusing. Can you direct me to a site of proper choices? I look forward to reading your information every day! A friend in the morning to help us through this!

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    1. Here's a link to a page with specific recommendations for 5 different portable air cleaners. https://www.montanawildfiresmoke.org/hepa-filters.html Also note the link they provide to recommendations from the California Air Resources Board if you want more.

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    2. There's a lot of resources out there for recommendations (Janice's comment, WireCutter, etc.), although the bigger concern is once you decide whether or not you can even purchase it or not. Most of the highly rated air cleaners are out-of-stock or having long delays being shipped. But if you don't intend on getting it really soon, the research is still valuable of course for a longer-term purchase.

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  16. My phone's weather app is saying that the AQI is 22... that can't be right?! AirNow is saying 203. Which one is the reliable one?

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    1. The airnow api was reporting only o3 (ozone) from about 8:15am - a little after 10am - whatever the glitch was seems to be fixed. (I'm not associated with it, I just have my own little app I wrote so I use the api)

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    2. AirNow and https://enviwa.ecology.wa.gov/home/map are more reliable than a 3rd party phone app. That said, your local instant air quality may be better or worse than what is shown on the airnow or state map. Those values represent the previous hourly average, with some influence from even earlier hourly averages. If conditions are changing rapidly the air at your house at any given moment could be better or worse. Without knowing more about how your phone app pulls data and calculates an AQI, I can't tell you how reliable it might be. The government sites pull their data directly from air monitors operated under specific quality control guidelines. They are the most trustworthy and transparent about how data is collected and reported.

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    3. As a general suggestion, would you consider adding the WAQA number ranges (12, 20, 35, 80, 150) to the map's color legend -- or perhaps somewhere persistent on the homepage, if that isn't possible? Or maybe just elevating it to its own bookmark-able blog post?

      I ask because I keep wondering things like "how close is (station X's Nowcast number) to the next breakpoint?" or "how does (station Y's Nowcast) compare with the AQI numbers & colors that my mom is seeing on her phone app?" But then I keep forgetting the numbers - because this isn't my field, and moreso I'm a big dumb-dumb - so I find myself digging around for Farren's comment (above) to reference them again and again.

      I understand this might be a niche request, in which case you're (obviously!) free/welcome to ignore it, but from reading the other comments I suspect that it would preemptively address a number of recurring questions that people seem to have.

      Cheers,
      CJ

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    4. I don't think the map or legend will change, and please keep in mind this blog and the map on it are in AQI (not WAQA). However, if you are interested in the actual concentrations and comparison to AQI/WAQA you can click on the dot get more info about the site. Concentrations are available on all these sites, including time series graphs that you compare to the AQI/WAQA time series. If you do that though, then you have to factor in how NowCast affects the AQI value.

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  17. Where do you stand on information provided by Copernicus Atmosphere Monitoring Service (used by Weather Underground) for accuracy in reporting AQI? Thanks.

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    1. For observational inputs, CAMS almost certainly uses the same air monitors as all the other sites. If they have the algorithm for calculating AQI correct, it should be the same as airnow.gov. I use the CAMS model, along with HRRR and others, to look at where smoke will go in the near future, but don't trust the absolute concentration. It's almost impossible to predict how much smoke any given fire will inject into the atmosphere in near or not so near future. The amount of smoke can also change the weather, which forecast models don't always capture. So between getting the emissions correct and capturing feedbacks, I say use with caution. Maybe one of the air quality modelers can chime in here too.

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  18. Thanks so much for these extremely helpful blog posts. Do you have any idea why the Oregon coast is seemingly doing so much better than the Washington coast? Or are there just fewer sensors on the Washington coast? (The southern part of the WA coast, below the Sound, I mean).

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    1. If you look at today's Terra MODIS image you can clearly see the channel of fresh marine air pulled up from the south. The same thing was visible yesterday as well. The low pressure system (and others after it) will soon be bringing rain and marine air to the Pac NW.

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