Aircraft observations and GISS ModelE simulations of black carbon from polluted outflow to remote oceans

Weakening removal by rain and snow below clouds also increases the total amount but produces a different vertical response. Delaying the tested particle-aging transition mainly changes particle composition, with little effect on the total amount. In this study, the main regional contrasts persist when observation weights are changed or selected deployments are excluded, whereas assessments of the remote-ocean mean depend more strongly on sampling.

These results show that retaining more black carbon in the atmosphere does not necessarily improve its regional distribution. Apparently reasonable global amounts or mean concentrations can also conceal compensating errors across regions. Improving simulations requires examining how much black carbon is present, where it occurs, and which particles carry it, together with emissions, vertical transport, and cloud processes, to better understand its atmospheric distribution and climate implications.</p>