There has been a debate in the air quality community about how to report air pollution to the public. Most countries have some sort of index, on a 0-10 or 0-100, or 0-500 scale. The index links to concentrations of common air pollutants, such as fine particles, ozone, SO2, each with their own concentration ranges representing their health threat. The public is often only told the color (yellow=moderate, orange=unhealthy, red=very unhealthy, etc.) While 35 micrograms per cubic meter may not mean much to most people, for those who want to compare air quality in different places or are perhaps more sensitive to one pollutant or another, this could be important information. Some of the U.S. sites do this pretty well, most do not. At the Smog Blog, we are often required to translate the AQI using several online sites.
Here in Malaysia, the Department of Environment has recently been criticized for just this lack of detailed information. During the peak of the haze we had a few weeks ago, the monitors were mostly 'moderate.' Only on the very worst of days did they edge into 'unhealthy.' I have been unable to find the concentration levels for the Malaysian API, which I would have thought could have been found at their informational website. Their monitors are very likely accurate but without the concentrations, it is hard to compare to other standards.
Posted by Jill Engel-Cox at August 25, 2009 6:52 AMWe're also facing the issue of how to report air quality data for Panama, and eventually additional countries in Central America. To complicate matters, there is the issue of reporting an AQI that is supposed to be a 24-hour average, but in the middle of the day before 24 hours of data are in. I believe we are leaning towards reporting only a concentration on a real-time basis, and then reporting a concentration and a color historically (for days past). Amy may know more recent information, but I'm interested in other comments too.
Posted by: Erica Zell at August 25, 2009 11:28 AMWell, we are having some technical problems with actually getting the real-time data from the University of Panama on-line, so we haven't had to address this problem yet. It will probably be several months before UP has the ability to upload their real-time measurements, so until then, we will only have "yesterday's" 24-hour average AQI values to report, which should be relatively straightford using the standard AQI. But I will be interested to see how our colleagues decide to report the real-time data, when the technical issues are resolved.
Posted by: Amy Huff at August 25, 2009 10:21 PMAIRNow using a statistical algorithm (developed by your colleagues in Columbus) to estimate the daily average AQI during the middle of the day. I believe there is a publication describing that on the AIRNow website. The process is quite different between ozone and PM due to the different temporal period of the standards (1 hour, 8 hour, 24 hour) and the variability of concentration over the day. I prefer concentrations with colors to AQI myself, but I am a minority.
Posted by: Jill Engel-Cox at August 25, 2009 10:57 PMThere is a pretty good summary of the AIRNow statistical method for estimating a 24-hour or 8-hour value before enough data is available. You can find it here: http://airnow.gov/index.cfm?action=airnow.faq
Feel free to give me a call for more in depth information.
Posted by: Scott Jackson at August 26, 2009 10:45 AMThere is a pretty good summary of the AIRNow statistical method for estimating a 24-hour or 8-hour value before enough data is available. You can find it here: http://airnow.gov/index.cfm?action=airnow.faq
Feel free to give me a call for more in depth information.
Posted by: Scott Jackson at August 26, 2009 10:46 AM