Dear Friend of SSV,
As we all struggle through Spare the Air Day #23 Month of wildfire smoke and high heat, we wanted to share some re-breaking “news you can use." You probably have PurpleAir.com on your desktop and phone and check it if you are lucky enough to time your ventures outside. In these smoky times, it is a very good idea.
The problem, however, is that the proliferation of widespread "low cost sensors" doesn't quite yield professional grade AQ data like the one (only one) Environmental Protection Agency site between San Jose and San Francisco. The workaround is to use correction factors, filters that help accommodate different types of pollution with different particle densities. It turns out wood smoke is a different animal than your run-of-the-mill polluted air. PurpleAir's default is 'none' (see blue arrow); to get a more accurate reading we had been recommending LRAPA but now EPA is advising AQandU (cute, huh?) as the better option when the regular numbers approach 150. The other news is that EPA will debut their very own factor real soon. Kudos to @EricaJoy for flagging this on Twitter. For those keeping score at home, more information here (a real good backgrounder) and here for maximum nerd cred (an EPA paper entitled “PurpleAir PM 2.5 U.S. Correction and Performance During Smoke Events").
Speaking of air, we recently held an AQ Talk with SSV’s Chief Scientist, Dr. Anthony Strawa, for the East Palo Alto (the other EPA) community on the practical aspects of installing Purple Air sensors. The map above (blue circle) is starting to show some progress with sensors in EPA.
Over the summer, SSV launched WET (Water, Environment, Technology) Talks kicked off by noted water diva, esteemed SSV water advisor and now Stanford William C. Landreth Visiting Fellow Felicia Marcus. We followed up with "Cry Me a River" featuring Dr. Sarah Diringer of the Pacific Institute and Peter Dreckmeier of the Tuolumne River Trust.
Lastly, we are pleased to share a taste of SSV's newest initiative, Sustainable Life, rolling out in the coming weeks. This is a different direction for us but one that we’ve come to recognize as vital, since it involves how well all live, breath, eat, etc. We hope you find these personal stories of SSV volunteers from both sides of the globe as inspiring and motivating as we did.
Keep cool, wear a mask, viva la vida,
Jennifer Thompson & Dennis Murphy
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