This study reports black carbon (BC) characteristics and climate effects for a 22-month period during 2018–2020 at a receptor location in the eastern Indo-Gangetic Plains (IGP). The overall averaged BC mass concentration was 7.8 ± 4.7 μg m⁻³, and the nighttime average (9.1 ± 6.1 μg m⁻³) was nearly double that of the daytime (5.8 ± 3.5 μg m⁻³). BC was most enhanced during winter, with mean concentration (14.3 ± 3.8 μg m⁻³) higher by 4 times as compared to summer. A two-component mixing model, frequency distribution of the Angstrom exponent, and a simultaneous increase in brown carbon (BrC) absorption coefficient suggested that this enhancement was mostly due to the biomass burning (BB) fraction of BC. CALIPSO-derived products showed that the extinction coefficient was highest at 0.62 ± 0.31 km⁻¹ in winter and lowest at 0.12 ± 0.05 km⁻¹ in summer. Backscatter plots and particle depolarization ratios indicated presence of spherical dust particles during summer and smoke plumes during post-monsoon and winter. Concentration-weighted trajectories (CWTs) helped in quantifying significant contributions of the IGP outflow to BC, BC-BB and BrC absorption. Finally, a large direct radiative forcing of the atmosphere by BC (37 ± 22 W m⁻²) was estimated via the radiative transfer model SBDART, with an associated atmospheric heating rate of 1.02 K d⁻¹.

• Higher BC during post-monsoon and winter with nighttime enhancements.
• Skewed Angstrom exponents in these seasons suggest contribution from BrC.
• Backscatter coefficient profile suggests impacts of smoke plumes.
• CWTs indicate NW-IGP outflow as the major contributor of biomass burning aerosol.
• Significant BC-induced direct radiative forcing estimated for the atmosphere.