****Update on January 17

The air quality from China is now collected from 85 cities. This extends the coverage to three countries (United States, United Kingdom, Hong Kong, and China). Hong Kong appears to maintain separate environmental oversight.

An interesting consideration for me as a map maker is whether judgements should be placed on the air quality content provided. One country's standard of health may differ from anothers. The monitoring stations generally report as a current health standard, based on their interpretations of underlying data. Therefore variations are expected.

In the case of the Chinese update, the Chinese did not provide locations, but names of their air stations. Wikipedia appeared to be the best approach to locate the cities.

Technically, there remain issues as to how to present the various health legends as one zooms from one country to another. There are (as in the Chinese) language issues as well.

My next addition will be Mexico, and likely further European Union countries.

Air quality data is collected around the world. This is an effort to collect in one place the various air monitoring station. The data is refreshed hourly. A challenge is how to reconcile how various governments have different standards for air quality. You will discover:

- United States Air Quality
- United Kingdom Air Quality
- Hong Kong Air Quality

The balloon style is uniform from country to country, in this case Hong Kong:

You can observe:
- A view based legend (country specific) that floats into view.
- A standard balloon style with a photo when available. (In the US they are webcams)
- An Air Pollution summary, the table column heading vary by country to reflect country differences.
- A link to the specific station information
- A link to the agency.
- Information as to when the scrape of air station was done, and an indication that this is not the Agency's presentation (to limit their liability).

The layer works reasonably well in Google Maps (except for the view based legends, and some content does not show)

Obviously, the next steps are to bring in more countries, and to address the Google Maps challenges.