Overview
- CEEW says the AQEWS correctly forecast 83 of 92 ‘very poor and above’ days in winter 2023–24 and 54 of 58 in 2024–25.
- The system’s detection of the most severe pollution days improved yet remained weak, rising from 1 of 15 (2023–24) to 5 of 14 (2024–25).
- Forecasts systematically underpredicted particulates, with PM2.5 MAPE near 35% and PM10 at 37–38%, and errors surging to 73% (PM2.5) and 57% (PM10) in late winter 2024–25.
- The DSS runs only in winter and relies on old emission inventories (TERI 2016 for NCR, SAFAR 2018 for Delhi), leading CAQM to stop using the DSS for decisions in December 2024.
- Policy actions were largely reactive, with GRAP Stage III imposed six times and Stage IV twice in 2024–25 after thresholds were breached, prompting calls for year-round DSS, bias-corrected high-resolution models, frequent national inventory updates, and public data access.