Delhi’s annual average ozone rose from 52 µg/m³ (micrograms per cubic metre) in 2021 to 66 µg/m³ in 2025, alongside a sharp increase in ozone-dominant days, from 33 µg/m³ in 2024 to 76 µg/m³ in 2025. A public air quality dashboard on Central Pollution Control Board (CPCB) data since 2015, launched by Delhi-based research and public policy think tank Envirocatalysts, has highlighted a shift in the Capital’s pollution pattern – decline in nitrogen dioxide and carbon monoxide emissions are accompanied by a growing challenge from ozone. The dashboard, launched on Monday, enables pollutant-wise, long-term analysis of emissions across cities. In Delhi , fine particulate matter (PM2.5) and coarse particles (PM10), for instance, show a winter and post-monsoon peak. Between October and February, pollution levels rise sharply, aided by stagnant atmospheric conditions that trap emissions close to the ground.…