February 15, 2008
Good to Moderate Air Quality Across the US
Air Quality continued to improve today in California. Elsewhere, there were scatted monitors in the moderate range. The Airnow map to the left shows actual PM2.5 concentrations for today at 6PM. Overall, aerosol levels were highest over the southeast, midatlantic, and parts of the south-central US. Notice that this is not the regular AQI scale. Click here to view these daily PM2.5 concentrations maps.
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And here is a PM2.5 and Air Quality Index timeseries for the last 10 days in DC. The last couple days, PM levels have increased some, but still within the green (good) range.
Where did the new AQ color scale come from?
Posted by: Ray Hoff at February 15, 2008 9:30 PMRay, from this great airnow web site Bill Ryan told me about years ago:
http://www.airnowdata.org/pmfine/latest.html
This scale relates to the actual 1 hour concentrations, instead of the 24-hour average Air Quality Index (AQI). The AirNowData website says "1-hour scale is arbitrary. These are not AQI colors." However, I think they provide more quantitative information, although without the health link of the AQI.
Posted by: Jill Engel-Cox at February 17, 2008 8:01 PMIsn't there a chance that these colors will confuse people as compared to the AQI?
Sure confused me.
Posted by: Ray Hoff at February 17, 2008 10:31 PMI like it because sometimes is it nice to look at the actual PM2.5 concentrations and I find it useful because there is a larger range of colors, i.e you can pick out the variability in the pm a little better than with the AQI, but yes the colors are arbitrary and not equivalent to the AQI.
Posted by: Ana Prados at February 20, 2008 1:17 PM