Marine stratocumuli cool the Earth effectively due to their high
reflectance of incoming solar radiation, and persistent occurrence. The
susceptibility of cloud albedo to droplet number concentration
perturbations depends strongly on large-scale meteorological conditions.
Studies focused on the meteorological dependence of cloud adjustments
often overlook the covariability among meteorological factors and their
geographical and temporal variability. We use 8 years of satellite and
reanalysis data sorted by day and geographical location to show that
large-scale meteorological factors, including lower-tropospheric
stability, free-tropospheric relative humidity, sea surface temperature,
and boundary layer depth, have distinct covariabilities over each of the
eastern subtropical ocean basins where marine stratocumulus prevail.
This leads to markedly different monthly evolution in albedo
susceptibility over each basin. Our results stress the importance of
considering the geographical distinctiveness of temporal meteorological
covariability when scaling up the local-to-global response of cloud
albedo to aerosol perturbations.