The natural environment is an important source of atmospheric aerosol such as dust, sea spray, and wildfire smoke. Climate controls many of these natural aerosol sources, which, in turn, can alter climate through changing the properties of clouds and the Earth’s radiative balance. However, the Earth’s atmosphere is now heavily modified by anthropogenic pollution aerosol, but how this pollution may alter these natural aerosol–climate feedbacks has not been previously explored. Here we use a global aerosol microphysics model to analyze how anthropogenic aerosol alters one link within these feedbacks, namely, the sensitivity of cloud albedo to changes in natural aerosol.