AQI / CAQI for nowcast

[HansR]

Something which has troubled me for some time was an anomaly in the AQI's for the EU (possibly also for the other countries).

CMX provides the AQI for measured concentrations and does so for the now, 1 hr and 3 hr concentrations in the same way.
CMX also provides the AQI for the 24 hr and the nowcast but uses a different concentration.

As the nowcast concentration follows the 3 hr average pretty close I think it should have the same AQI as the 3 hr average otherwise you get anomalies as in the table below (chart exists if that would make things clearer). This holds at least for the EU AQI and CAQI standards.

I think for the nowcast AQI, CMX should use the same functions as for the 3 hr average.

Schermafbeelding 2022-08-29 133601.jpg

[mcrossley]

Nowcast is a funny one isn't it. It uses 24 hours of data but with a heavy bias towards recent readings. Is it actually recognised anywhere?

But looking at your figures it may be better to use the 3 hour scale.

[HansR]

Nowcast is a funny one isn't it. It uses 24 hours of data but with a heavy bias towards recent readings. Is it actually recognised anywhere?

But looking at your figures out may be better to use the 3 hour scale.

Yes, think so too. Thanks.
Yes it is weird, it is American (development) and is used only there asfaik (compulsory in US devices)
There must be politics around it