<http://schema.org/description>
"Beijing is a bit notorious for its high air pollution levels which can sometimes get really bad. Sometimes you can see the entire city is covered in heavy smog.\u2026"^^<http://www.w3.org/2001/XMLSchema#string>
<https://www.photoblog.com/ljgarbanzos/2010/09/14/air-pollution-index-api/>