My colleague Dr. Beth Friedman crunched through statewide fine particle pollution data and prepared these plots comparing this year's smoke events against the last 5 years. The y- axis of the plot below shows the % of time all sites in the state recorded air quality in each of the stated categories. Monitor downtime and operating schedules have been accounted for. Only levels corresponding to an exceedence of the federal standard are shown for clarity.
Next question is where those conditions occurred (you guessed it: everywhere). Beth mapped out how different areas in WA compared against each other, by averaging concentrations from the highest 3 days for each site this September. The size of the circles is number of days greater than the federal standard.
Seems like southern Yakima county followed by parts of Okanogan County had the most number of polluted days this month, but the worst air was recorded in the Columbia River Gorge and Clark County. Northwest and southeast WA had the "cleanest" and fewest bad days, respectively.
Take home message: Not the longest we've had to endure crummy air, but this is the dirtiest air we've had to breath as a state. And the season isn't over yet.
Thanks for all the work you guys do, this information is very interesting.
ReplyDeleteGiven the (apparently historical) poor air quality, are there recommendations related to time spent outdoors? For example, is it safe to take my dogs on a brief walk, or walk a short distance to the grocery store? I think I've made myself paranoid learning all this new info...
The health studies don't really support that level of super refined advice about time outdoors, and hey sometimes a dog just needs a walk. If you're healthy and not in a sensitive group, it's not unreasonable to spend a little time outside. If you like details you can take a look at this document. https://www3.epa.gov/airnow/wildfire-smoke/wildfire-smoke-guide-revised-2019.pdf It's the most up-to-date and definitive guide on smoke and health available.
DeleteAny idea of the possible duration of this event? Hard to get any sense of that, with so many factors in play. Tri-Cities now on its 4th day of 400+ hazardous air.
DeleteHang in there, we think you should see a substantial improvement by Saturday
DeleteHelp me understand how we on the Eastside actually have blue skies right now in parts, but the smoke is still really bad. How does that work, meterologically?
ReplyDeleteCopying & pasting from two previous responses:
DeleteJust keep in mind there are layers in the atmosphere a lot of smoke aloft can turn the sun red, while air quality at the surface is good. On the flip side, a thin layer of PM2.5 pollution near the surface may not be visible, while air quality is still bad.
Smoke is certainly thinning aloft, I can see the Olympics in the satellite pictures, but the Cascades are shrounded by clouds. Hard to tell from webcams but some low cost sensors in the hills have been seeing a dip lately
So is the inversion is what’s causing the issue with air quality for the vast majority of the PNW? It’s not not letting the smoke disperse into the other layers of the atmosphere?
DeleteJosh, correct, it is trapping the smoke closer to the surface and preventing the winds aloft from mixing down.
DeleteThank you for your hard work to make this the best information source for smoke pollution!
ReplyDeleteGeeking out on your fabulous data viz is one of the few things keeping me grounded right now...thanks Dr. Friedman et al.!
ReplyDeleteI believe your science of course, but it just didn't seem like we were so "locked down" in any previous years of this stuff. Maybe we're all just more aware because of the severity this year? Or maybe I'm just more paranoid that previous years?
ReplyDeleteIt's more concentrated smoke vs previous years. See above post
DeleteZac, this kind of episode requires a lot of things to gang up on you. Last week's strong, sustained east wind event was unusual, but it wouldnt have done much if there wasn't so much smoke around to sweep offshore and pool over the Pacific. That pool also served as a reservoir for the CA & OR smoke. The strength and duration of the temperature inversion this week isnt unusual. But then when it taps into this huge pool of smoke offshore which only leaks over the state very gradually, you have the perfect storm.
DeleteJust want to say that’s such a good explanation!
DeleteYes the thickness and hazardous levels made it more dense and opressing. Fires were significant this year!
DeleteThanks for these updates. It has been literally the only useful info out there. If this is the “new normal” you and your coworkers should plan to keep this an ongoing resource. At times (hopefully) of no fires, it could cover air pollution, drought and fire risk on a regular (weekly?) basis. With the ability to surge to daily as you have been so ably doing during this crisis. Again, great work.
ReplyDeleteI second this! I would love to read an ongoing weather conditions blog from you folks! I used to like Cliff Mass... need an alternative to that now.
DeleteMe too on keeping up the great work! Ty!!
DeleteThank you for this work! I was looking for an analysis comparing the conditions now to 2018 and you nailed it. :)
ReplyDeleteIt'd be great if you could tackle in a post how to interpret the AQI standard vs. DOE's WAQA numbers. Maps look VERY different using DOE's WAQA with pretty significant implications for activity and health. Thank you!
ReplyDeleteThe current PM2.5 breakpoints for WAQA in micrograms per cubic meter are: 0-12 (good), 13-20 (moderate), 21-35 (USG), 36-80 (Unhealthy), 81-150 (Very UnH), (>150 Haz). For AQI the breakpoints aren't as strict: 12, 35, 55, 150, 250. Hope this helps.
DeleteMickaelK, I hear you! I had three different sources with very different information going for a while - I'm a scientist and rather tech savvy and it was unnerving to say the least. I finally found this explanation from the Olympic Region Clean Air Agency: https://www.orcaa.org/air-quality/current-air-quality/. The short story is that Washington has more protective standards than the EPA does (not uncommon for a lot of environmental metrics). Thanks to Ecology staff for working hard on communication now - it's so helpful! Please consider linking information about the distinction between WAQA and AQI in a clearer spot on the air quality monitoring home page.
DeleteThank you so much for sharing this analysis! Just out curiosity, I see you mentioned how the wildfire season isn't over yet. I'm thinking about how the hazardous levels we experienced were strongly influenced by California's wildfires, which their season obviously lasts much longer than ours. What would you say is the likelihood of this severe of an event happening again in the next few months where we are sitting in such hazardous air for such a sustained duration?
ReplyDeleteA 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.
DeleteThank you all so much for providing such useful information. Having some understanding of what is happening and why makes it easier to live with the unpleasantness. Appreciate your collective resourcefulness in finding ways to display your data. (Ed Tufte, even though he was a social scientist, would be admiring...)
ReplyDeleteThank you very much for sharing this analysis.
ReplyDeleteThank you for these thorough and candid reports! A numbers question: what is the difference between PM2.5 WAQA, used on the WA State Dept of Ecology interactive map (https://enviwa.ecology.wa.gov/home/map) reporting a current value of 319 at the Seattle-Duwamish station, versus the PM2.5 Air Quality values on your above map, reporting a current value of 184 at the same Seattle-Duwamish station? Creating confusion among friends (and news media reports) over levels of concern. Thanks!
ReplyDeleteThe current PM2.5 breakpoints (going from good to hazardous) for WAQA in micrograms per cubic meter are: 12, 20, 35, 80, 150. For AQI they are: 12, 35, 55, 150, 250. Hope this helps.
DeleteThanks for those details, but it'd be great to do a longer post if y'all can at some point. There is definitely confusion out there -- not just that AQI and WAQA have different breakpoints, but it seems that the DOE map / data uses a different scale, or does some conversion, to also express the PM2.5 numbers on the AQI scale. That is very confusing and the media and lots of people don't know how to interpret it.
DeleteIs this situation going to continue for the duration of the fires whenever the wind blows our direction?
ReplyDeleteNo. Wind direction is important but fires have to continue to producing enough smoke and send the plume high enough for it to get transported long distances.
DeleteI am curious to know how does this fire season compare to pervious years with regards to number of continuous days of smoke levels very unhealthy and above? Perhaps it is due to COVID19, but this feels like the longest stretch of days of very bad air quality in recent years over Western Washington. Has anyone looked at the data with regards to this equation/comparison?
ReplyDeleteEmmi, good question and this is something we're trying to figure out how best to present. Please stay tuned.
DeleteWhat’s interesting is that no one actually talks long term health damage this may have caused. Everyday summary is the same - “air is near-hazardous levels so stay inside”. I personally left the state after the first smoke wave last Monday and was hoping to return this week but now Indon’t see that happening either.
ReplyDeleteAny idea how this compares to historic 19th Century smoke events in Western Washington? Obviously we don't have modern measurements to compare, but do you know if anyone has good estimates of what levels would have been when smoke and ash were enough to damage fruit and grain crops in the 1890s?
ReplyDeleteHi J.. I don't have an answer to your question and I'm guessing neither do the others. I didn't want to leave you hanging. It's an excellent and interesting question, but one that requires a non-trivial amount of research. Maybe one of our readers can chime in.
DeleteRanil, what is the difference with the WA Ecology monitoring site readings that show a 300+ ppm readings in the Seattle area the last few days and then the Federal EPA which partners with AirNow shows air monitoring readings in the 230 ppm range? I’m curious why the readings are so different.
ReplyDeleteHi Josh, so Ecology's WAQA scheme is more protective of public health than EPA's AQI, and paints a bleaker picture (i.e. encourages you to take protective steps at lower levels). Its the same mass concentrations that are used in both calculations. WAQA only applies to PM2.5 (units are in micrograms per cubic meter, not ppm, BTW).
DeleteThis is great, but I don't quite understand what the first graph is showing, i.e. what "the % of time all sites in the state recorded air quality in each of the stated categories." Does that mean that in 2018, say, 40% of all monitor-hours throughout the state were Unhealthy or Above during the stated time period? Thanks for this helpful resource!
ReplyDeleteHi, yes it can be tricky to navigate through this and your second sentence is pretty close. It means that, for instance in 2018, 40% of all monitor-DAYS (not hours) throughout the state were Unhealthy or Above.
DeleteIf I need fresh air in my small apartment, can I seal with tape a Merv13 furnace filter in my small bathroom window? I don't have AC and its getting very hot inside (low 80s). Opening the window and letting in filtered air for even 10-15 minutes greatly helps.
ReplyDeletePlease comment! thanks for your work.
This is a great idea. Make sure you tape all around the filter and form a good seal so the smoke doesn't have another way in.
DeleteHow widespread are the monitors? The maps could be biasing towards higher concentrations of active monitors. Is that accounted for in deciphering the data and coming to these conclusions? For example, I'm imagining there's less monitors in the heart of the Olympic peninsula than there would be in the I-5 corridor along the Sound.
ReplyDeleteMonitoring is denser in populated areas because of their regulatory purpose, infrastructure needs, and maintenance access concerns. Widespread smoke/dust events highlight the lack of monitoring in low population areas. The forest service will put up temporary monitors near large wildfires (marked as triangles), but those are limited. There are also some "background" monitors across the US (e.g. Cheeka Peak), but those are sparse. The new fire.airnow.gov map with low-cost sensors plotted alongside regulatory monitors is also a great new tool which helps. Imagery and models help fill in the cracks.
DeleteThank you for the clarity. Also thank you for your blog! you are providing a wonderful resource especially during these uncertain and difficult times.
DeleteCould someone answer a Science 101 -type question for me? One of the hardest things about enduring this situation of closed windows is how stale and de-oxygenated the air in my apartment feels. I'm breathing the same air over and over again. I do have about 30 houseplants, among which six are medium-large specimens of NASA-recommended 'air-cleansing' species, but, in short, Where is my oxygen coming from? Of course there's some seepage around the windows, letting both smoke and air/oxygen in, but it's minimal. I'm expecting delivery of an air purifier later today or tomorrow, but that will not actually add oxygen. My headache seems to come as much from oxygen-poor air as from the smoke. How am I getting enough oxygen/Am I even getting enough? (How long can the body sustain health in de-oxygenated air?) I'd appreciate understanding this better. Thanks!!
ReplyDeleteTrapping yourself in a room doesn't deprive you of oxygen because the air is 20% oxygen and you don't exchange that much while breathing. What does change significantly is the carbon dioxide levels, which grow significantly as you breathe since concentrations are very low to begin with (fraction of a percent). When air in your room gets over 0.1% CO2, you could notice drowsiness and even start getting headaches and other symptoms. You may want to invest in a CO2 monitor if you are concerned about that.
DeleteIs it my imagination (and forgive me if you covered in a previous post), or does the air quality worsen throughout the day? Around this time each day we start to notice the smell getting worse indoors. If so, is that due to atmospheric heating?
ReplyDeleteWildfires typically produce more smoke as things heat up and there is more fire activity later in the day. So, if you are downwind of any relatively fresh smoke, it could get worse throughout the day. Depending on location, though, you can see the opposite effect where air gets worse at night because of mountain valley drainage of smoke. It's also possible that your indoor air appears worse during the day because there is more activity inside (dust, cooking, opening doors, etc.).
DeleteThanks, Farren!
DeleteHi. As a sufferer of copd I have come to depend on your site for the clearest and best information about the air quality. I used to use Airnow but their maps are not as user friendly to me. Thank you for this indispensable resource! You're literally saving lives with the work you do.
ReplyDeleteI want to thank you for all the great work you do and have done for us all -- I sincerely appreciate all the effort you put in to providing us updated air quality information to keep us safe and well informed. And fun to read too :) You're great and can't thank you enough!
ReplyDeleteMolly and Brandon - from Shoreline