The city is racing to put up 277 sensors. Once installed, Chicago will have the most high-quality air monitors in the country, a model that rivals only London, which has more than 400.By Brett Chase, Chicago Sun-TimesCity officials are scrambling to install nearly 300 high-quality air pollution sensors across Chicago, a network that would be the largest in the U.S. and one of the biggest worldwide.
Observations from the Little Bunker
Last updated: August 18, 2025 04:13 PM
Atmospheric CO₂
425.4 ppm
+18.4
ppm/year
Atmospheric CH₄
1934.91 ppb
+9.11
ppb/year
Global Temperature
+1.48 °C
Peak: +1.73°C
World Population
8.1 billion
+67
million/year