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Black carbon (BC) aerosols strongly absorb solar radiation, but their effective radiative forcing and impacts on regional climate remain highly uncertain owing to strong feedbacks of BC heating on clouds, convection, and precipitation. This study investigates the role of large-scale circulation changes in governing such feedbacks. In the HadGEM3 climate model BC emissions were increased to 10 times present-day values while keeping sea surface temperatures fixed, to assess the rapid adjustments to increased BC absorption. The BC perturbation led to an effective radiative forcing of 2.7 W/m(2) and a 0.13-mm/day reduction in global precipitation. There were also large shifts in the spatial distribution of tropical convection, increased low cloud over oceans, and a weakening and poleward shift of midlatitude storm tracks, especially in the Northern Hemisphere. In a parallel experiment, horizontal winds were nudged toward meteorological reanalyses to deliberately suppress circulation responses while allowing changes to the thermodynamic structure of the atmosphere. Surprisingly, BC had approximately the same impact on global-mean radiation and global precipitation in the nudged experiment, even though regional changes in clouds and convection were not fully captured. The results show that large-scale dynamical responses to BC are important for regional impacts but have a limited role in determining the effective radiative forcing and global-mean climate response. The rapid adjustments of clouds, radiation, and global precipitation were primarily a response to increased radiative absorption and atmospheric stability. This implies that short nudged simulations may be sufficient to assess absorbing aerosol impacts on global-mean radiation and precipitation.