Biomass burning in South Asia is a significant contributor to global emissions of black carbon, the second most important greenhouse agent after carbon dioxide. Emissions from domestic fires are the largest contributor to biomass burning but may be costly to mitigate. Open-field burning is the second-largest contributor to black carbon in South Asia. This study uses primary field data to identify the determinants of emissions from open-field burning of crop residue with the aim of analyzing possibilities for its regulation. The effectiveness of a new seeding machine that lets farmers plant their crops without having to burn the residue from the previous crop is assessed. A comparison of the new machine with conventional practice shows that the new technology decreases field preparation costs but does not significantly impact crop yield and profits. The use of plot-level data with farmer fixed effects enables reliable identification of the impacts of the technology. Given the considerable adverse effects on mortality and health of pollution from burning, these results imply that this source of black carbon can be mitigated at zero private cost and negative social cost. Since farmers have no strong private incentive to adopt the new technology, extension, and subsidies to accelerate adoption would be a high net-benefit policy.
