GCMs With Full Representation of Cloud Microphysics and Their MJO Simulations

Abstract This chapter reviews three types of general circulation models (GCMs), with full representation of cloud microphysics, and examines their simulations of Madden-Julian Oscillation (MJO). The models include a global cloud-resolving model (global CRM) with an ultrahigh horizontal resolution of an order of a few kilometers, the so-called superparameterized global model with CRMs embedded in each GCM grids, and a GCM with full representation of cloud microphysics and scale adaptive cumulus parameterization at a medium-range horizontal resolution of 50 km. The development strategies of those GCMs and the simulation qualities of their precipitation climatology and MJO are discussed. Although those GCMs are sensitive to the parameters and schemes in the CRM physics, full cloud microphysics appears to create a better simulation of the MJO than a simple precipitation formula of cumulus parameterization in conventional GCMs. However, the GCMs with full cloud microphysics are still at an early stage in terms of understanding and simulating many observed aspects of weather and climate.