Scientists at the Indian Institute of Tropical Meteorology (IITM) Pune found that fewer than 3% of raindrop-forming cloud droplets during the 2018-19 monsoon over Solapur, Maharashtra contained black carbon. Black carbon is a pollutant from burning fossil fuels and biomass that can alter rainfall patterns and affect climate. The team used aircraft equipped with instruments to fly through monsoon clouds and measure black carbon levels. The study revealed that black carbon concentrations were much higher below the clouds than inside them, sometimes up to 100 times less within the clouds themselves. Natural cloud processes appear to exclude most black carbon, which helps improve weather models for India's monsoon season. Understanding how clouds filter black carbon is important for predicting rainfall and climate impacts in the region.
