The story: Heavy air pollution, exacerbated by a phenomenon known as temperature inversion during the cold season, is common in the Iranian capital. However, hazardous emissions have been particularly stubborn this year, blanketing Tehran’s skies for 23 days in a row. Authorities have been scrambling to find a solution, but to no avail so far.

The coverage: Regardless of their political leanings, Iranian media outlets have in the past three weeks been focusing on the pressing issue of pollution in Tehran...