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arianna Nov 30, 2017 09:13 AM
Dear EEA forum, I’m Arianna from Bologna (Italy). I have seen the Air Quality maps and I would like to have more information about the indicator. Are the hourly data (O3, NO2, SO2) validated? And PM10 and PM2.5 data? If I look at maps with 6-hours resolution what kind of data do I see? For PMx I suppose the value about yesterday, instead of NO2?
Lastly, I would like to know if the data are linked to each local agency or national agency in every country.

Thank you in advance and for this service
Kind regards,
Replies (1)
EEA Dec 01, 2017 11:21 AM

The AQ index is based on data officially reported on an hourly basis by the EEA member countries, so data are not verified for any of the five pollutants used in the estimations. At any time, for NO2, O3 and SO2 you see the hourly value at that hour, and for PMx the running 24h mean. So, if now it is 12 am and you look at period = “6 hour ago” you will see the concentrations at 6 am for NO2, O3 and SO2; and for PMx, the average of the 24 hourly values between 6 am yesterday and 6 am today.

Finally, you can find links to data providers in the up-to-date data viewer ([…]/up-to-date-air-quality-data), in the box that pops up when clicking on a station. This viewer presents the data used to calculate the AQ index.

Kind regards