Potential impacts of Asian carbon aerosols on future US warming

This study uses an atmosphere-ocean fully coupled climate model to investigate possible remote impacts of Asian carbonaceous aerosols on US climate change. We took a 21st century mitigation scenario as a reference, and carried out three sets of sensitivity experiments in which the prescribed carbonaceous aerosol concentrations over a selected Asian domain are increased by a factor of two, six, and ten respectively during the period of 2005-2024. The resulting enhancement of atmospheric solar absorption (only the direct effect of aerosols is included) over Asia induces tropospheric heating anomalies that force large-scale circulation changes which, averaged over the twenty-year period, add as much as an additional 0.4°C warming over the eastern US during winter and over most of the US during summer. Such remote impacts are confirmed by an atmosphere stand-alone experiment with specified heating anomalies over Asia that represent the direct effect of the carbon aerosols.