Data from: Insensitivity of the cloud response to surface warming under radical changes to boundary layer turbulence and cloud microphysics: results from the ultraparameterized CAM

This data set contains the simulation outputs used in the study summarized
below: We study the cloud response to a +4K surface warming in a new
multiscale climate model that uses enough interior resolution to begin
explicitly resolving boundary layer turbulence (i.e.,
ultraparameterization or UP). UP's predictions are compared against
those from standard superparameterization (SP). The mean cloud radiative
effect feedback turns out to be remarkably neutral across all of our
simulations, despite some radical changes in both cloud microphysical
parameter settings and cloud‐resolving model grid resolution. The overall
low cloud response to warming is a positive low cloud feedback over land,
a negative feedback (driven by cloud optical depth increase) at high
latitudes, and weak feedback over the low‐latitude oceans. The most
distinct effects of UP result from tuning decisions impacting
high‐latitude cloud feedback. UP's microphysics is tuned to optimize
the model present‐day, top‐of‐atmosphere radiation fluxes against CERES
observations, by lowering the cloud ice‐liquid phase shift temperature
ramp, adjusting the ice/liquid autoconversion rate, and increasing the ice
fall speed. This reduces high‐latitude low cloud amounts and damps the
optical depth feedback at high latitudes, leading to a slightly more
positive global cloud feedback compared to SP. A sensitivity test that
isolates these microphysical impacts from UP's grid resolution
confirms that the microphysical settings are mostly responsible for the
differences between SP and UP cloud feedback.