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Realtime California Air Quality

purpleair.com

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Re: Realtime California Air Quality

#31

Post by tmpz22 »

krat0sprakhar wrote: post #30
ilyagr wrote: post #23

I've found http://www.airnow.gov very helpful and faster to load than the Purple Air map. They also have a simple but efficient app. Airnow's map is slow to load, but shows smoke, air monitors (including the Purple Air ones^[footnote]), and fires all at once: https://fire.airnow.gov/?lat=37.40&lng=-122.077&zoom=10# A less detailed, fast, static map for the SF Bay Area is available at http://www.baaqmd.gov . Last, but…

Didn't know about airnow.gov - thanks! I'm surprised though why the data is so different between airnow and purpleair. On AirNow, SF currently shows unhealthy air (150~) whereas purpleair shows 88 (moderate). Which one of these is more reliable and real-time?

Purple air has a mix of indoor sensors, try using the filter to hide indoor sensors and you should see more of a parity between the two.

Re: Realtime California Air Quality

#32

Post by gonehome »

krat0sprakhar wrote: post #30
ilyagr wrote: post #23

I've found http://www.airnow.gov very helpful and faster to load than the Purple Air map. They also have a simple but efficient app. Airnow's map is slow to load, but shows smoke, air monitors (including the Purple Air ones^[footnote]), and fires all at once: https://fire.airnow.gov/?lat=37.40&lng=-122.077&zoom=10# A less detailed, fast, static map for the SF Bay Area is available at http://www.baaqmd.gov . Last, but…

Didn't know about airnow.gov - thanks! I'm surprised though why the data is so different between airnow and purpleair. On AirNow, SF currently shows unhealthy air (150~) whereas purpleair shows 88 (moderate). Which one of these is more reliable and real-time?

I think purple air is better.

Purple air relies on a bunch of devices people have bought and installed all over. I think airnow is just a handful of government ones?

Re: Realtime California Air Quality

#33

Post by gnutun »

krat0sprakhar wrote: post #30
ilyagr wrote: post #23

I've found http://www.airnow.gov very helpful and faster to load than the Purple Air map. They also have a simple but efficient app. Airnow's map is slow to load, but shows smoke, air monitors (including the Purple Air ones^[footnote]), and fires all at once: https://fire.airnow.gov/?lat=37.40&lng=-122.077&zoom=10# A less detailed, fast, static map for the SF Bay Area is available at http://www.baaqmd.gov . Last, but…

Didn't know about airnow.gov - thanks! I'm surprised though why the data is so different between airnow and purpleair. On AirNow, SF currently shows unhealthy air (150~) whereas purpleair shows 88 (moderate). Which one of these is more reliable and real-time?

A useful explanation of the differences: https://medium.com/@16fcali/562923a55226

Re: Realtime California Air Quality

#34

Post by jeffbee »

avmich wrote: post #8
RobLach wrote: post #5

Earlier quoted context omitted.

Unfortunately the same conditions are reappearing which will negatively compound the situation: https://www.chicoer.com/2020/08/23/national-weather-service-...

> A map of the Red Flag Warning can be found on the US National Weather Service’s Facebook page. Anything more available?

The map basically shows the entire state of California. Saved you a click.

Re: Realtime California Air Quality

#35

Post by karlding »

krat0sprakhar wrote: post #30
ilyagr wrote: post #23

I've found http://www.airnow.gov very helpful and faster to load than the Purple Air map. They also have a simple but efficient app. Airnow's map is slow to load, but shows smoke, air monitors (including the Purple Air ones^[footnote]), and fires all at once: https://fire.airnow.gov/?lat=37.40&lng=-122.077&zoom=10# A less detailed, fast, static map for the SF Bay Area is available at http://www.baaqmd.gov . Last, but…

Didn't know about airnow.gov - thanks! I'm surprised though why the data is so different between airnow and purpleair. On AirNow, SF currently shows unhealthy air (150~) whereas purpleair shows 88 (moderate). Which one of these is more reliable and real-time?

Someone posted a Medium article [0] on the /r/bayarea subreddit where they did some digging into this. Apparently the sensors used by Purple Air rely on a constant that represents the average density of the particles it detects. Because wood smoke particles are less dense than typical PM 2.5 particles, the resulting AQI values are too high.

The Lane Regional Air Protection Agency has developed a conversion formula that is built into Purple Air (if you apply the LRAPA conversion factor in the UI), so you can have a better comparison.

[0] https://medium.com/@16fcali/understanding-purpleair-vs-airno...

Re: Realtime California Air Quality

#36

Post by tjohns »

krat0sprakhar wrote: post #30
ilyagr wrote: post #23

I've found http://www.airnow.gov very helpful and faster to load than the Purple Air map. They also have a simple but efficient app. Airnow's map is slow to load, but shows smoke, air monitors (including the Purple Air ones^[footnote]), and fires all at once: https://fire.airnow.gov/?lat=37.40&lng=-122.077&zoom=10# A less detailed, fast, static map for the SF Bay Area is available at http://www.baaqmd.gov . Last, but…

Didn't know about airnow.gov - thanks! I'm surprised though why the data is so different between airnow and purpleair. On AirNow, SF currently shows unhealthy air (150~) whereas purpleair shows 88 (moderate). Which one of these is more reliable and real-time?

AirNow uses official EPA sensor sites, which are professionally maintained but fewer in number. These will have the highest quality data.

That said, the PurpleAir devices use high quality laser particulate sensors, so they're still significantly more accurate than most consumer devices.

Both are real time, but during a wildfire where smoke is shifting between neighborhoods, I'd go with the PurpleAir site to get a score for your particular neighborhood. Just be sure to turn on the LRAPA scoring model, as others have mentioned.

Re: Realtime California Air Quality

#37

Post by ilyagr »

krat0sprakhar wrote: post #30
ilyagr wrote: post #23

I've found http://www.airnow.gov very helpful and faster to load than the Purple Air map. They also have a simple but efficient app. Airnow's map is slow to load, but shows smoke, air monitors (including the Purple Air ones^[footnote]), and fires all at once: https://fire.airnow.gov/?lat=37.40&lng=-122.077&zoom=10# A less detailed, fast, static map for the SF Bay Area is available at http://www.baaqmd.gov . Last, but…

Didn't know about airnow.gov - thanks! I'm surprised though why the data is so different between airnow and purpleair. On AirNow, SF currently shows unhealthy air (150~) whereas purpleair shows 88 (moderate). Which one of these is more reliable and real-time?

I think the main difference is that airnow mainly relies on expensive sensors with government-approved calibration. There are only a few such sensors per county.

Airnow's map shows both the government sensors and the Purple Air sensors, but that seems to be a recent "pilot project". I doubt they use the low-cost sensor data anywhere else.

Re: Realtime California Air Quality

#39

Post by claydavisss »

coronadisaster wrote: post #7
RobLach wrote: post #5

Earlier quoted context omitted.

Unfortunately the same conditions are reappearing which will negatively compound the situation: https://www.chicoer.com/2020/08/23/national-weather-service-...

at least, those 1500 square miles can't burn again... maybe CA need to do controlled burns like FL does (if they don't already do it). IE: Burn dry brush in the forests.

It may be too late. The high-risk areas are very close to homes (as is evidenced by the destruction of property). A controlled burn near homes will produce high volumes of smoke even if they are controlled. If they are not adequately controlled, you can lose a town.

Depopulating these areas won't need to happen by edict, insurances premiums will do that. If these trends continue, there will be no one living in the quaint gentleman-farmer communities in wine country within twenty years.

I predict the sierras will be the next danger zone - as more people move to the Tahoe area, all of the mistakes of sprawl will be repeated.

Re: Realtime California Air Quality

#40

Post by scurvy »

ilyagr wrote: post #23

I've found http://www.airnow.gov very helpful and faster to load than the Purple Air map. They also have a simple but efficient app. Airnow's map is slow to load, but shows smoke, air monitors (including the Purple Air ones^[footnote]), and fires all at once: https://fire.airnow.gov/?lat=37.40&lng=-122.077&zoom=10# A less detailed, fast, static map for the SF Bay Area is available at http://www.baaqmd.gov . Last, but…

AirNow's data _can_ be less accurate. For example, punching in a Lamorinda ZIP code only returns results for Oakland ("Oakland reporting area"), even if the ZIP correctly shows the right locale.

PurpleAir lets me see my neighbor's air quality stats...two houses away. PurpleAir is much more relevant and accurate for me.

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