Sensitivity of the atmospheric energy budget to two-moment representation of cloud microphysics in idealized simulations of convective radiative quasi-equilibrium

Sensitivity of the atmospheric energy budget to two-moment (2M) representation of cloud microphysics in idealized convective radiative quasi-equilibrium (CRQE) is studied using partial and full 2M schemes. The focus is especially given to the sensitivity to 2M scheme for large hydrometeors. The atmospheric energy budget is found to be sensitive to the first indirect effect, but the energy budget is more sensitive to the 2M treatment for large hydrometeors. The top and bottom of atmosphere (TOA and BOA) energy budgets depend on 2M treatment especially for large ice hydrometeors (snow and graupel). The predicted number concentration of graupel dominates BOA energy budgets by increasing rain size leading to decrease of sensible heat flux, and that of snow dominates TOA energy budgets by enhancing updraught cloud mass flux in both low and middle clouds. In conclusion, the energy budgets are controlled not only by 2M representation of rain but also by representation of large ice hydrometeors. Sensitivity of the energy budget to 2M treatment for large ice hydrometeors is more significant than that for rain because the treatment impacts properties of surface heat fluxes and both low and mid-level clouds.