Black carbon characterization and its association with meteorological phenomena using network data.

Abstract

Studies related to the impact of Black Carbon (BC) aerosols on weather phenomena like monsoon breaks, winter fog events, and pre-monsoon heatwaves are sparse in India. This study fills the gap of observational information of BC aerosols and their relationship with meteorological phenomena. We examined the interaction between BC aerosols and precipitation during the monsoon's active-break cycle, a critical period for agriculture, water resources, and weather patterns. Data from stations in rural and urban areas provided contrasting seasonal and diurnal variation. The diurnal pattern is closely linked to anthropogenic activities and meteorological factors. The study examines significant diurnal and seasonal variation in relation to local and regional meteorological variation. BC concentrations show distinct bimodal diurnal patterns, with major peak in the evening, between 2000 to 2300 h IST and secondary peak in the morning between 0700 to 0900 h IST. Seasonal variations show the lowest BC levels during the monsoon due to efficient wet scavenging, while the highest levels occur during the post-monsoon, primarily from agricultural burning. Meteorological factors like temperature, humidity, rainfall, and wind speed significantly influence BC dynamics. Higher temperatures and lower humidity increase BC levels, while rainfall reduces them, and wind disperses BC aerosols, affecting their concentration and distribution. Analysis of pre-monsoon heatwaves, winter fog events, and monsoon conditions reveals the complex interplay between BC aerosols and weather patterns. Local meteorological factors such as temperature inversions and wind patterns significantly influence the BC impact on weather phenomena. This research enhances the understanding of BC pollution and its diverse effects on weather and climate, emphasizing the importance of integrating meteorological factors into air quality management and policymaking. It lays the groundwork for developing targeted strategies to mitigate BC's adverse effects on health and the environment in India.