Study links most year-to-year winter PM2.5 variation in north India to western disturbances

Researchers reported that about 70% of the year-to-year variation in winter air pollution across northern India can be explained by the frequency of western disturbances, which increase ventilation and bring precipitation that helps clear pollutants such as PM2.5. The study also found western-disturbance frequency is linked to ocean temperature patterns evident in the preceding autumn, suggesting seasonal predictability of overall winter pollution severity.