Interstate transport of carbon monoxide and black carbon over India

The contribution of interstate pollution transport to surface carbon monoxide (CO) and black (BC) levels in different Indian states regions is studied by implementing a computationally efficient tagged tracer technique the Weather Research Forecasting model coupled with chemistry. Anthropogenic fire emissions CO BC are tracked from each state simulated concentrations used estimate state-wise pairs source receptor 2014, most recent year for which anthropogenic available. We observe strong relationship between direct local contributing 56–68% annual averaged Uttar Pradesh, Delhi, West Bengal located Indo-Gangetic Plain. Interstate contributes 53 ± 23% 52 25% BC, respectively, states. exceeds 60% one third Bengal, Maharashtra, Bihar among top five contributors Seasonal changes monsoonal circulation also led reversal source-receptor at level winter summer monsoon seasons. Our findings imply need extend India's air quality management framework address exchange pollution.