Beyond deadlock

[1] Today's atmospheric global circulation models can represent the effects of clouds through “conventional” parameterizations on coarse grids, through the use of global high-resolution grids, or through the use of embedded cloud-resolving models as superparameterizations in a lower resolution global model. Recent work on conventional parameterizations has been aimed at improving the representation of entrainment, including nondeterministic effects, and achieving resolution independence. Global high-resolution grids have been very useful for studying the interaction of clouds with the global circulation out to time scales of about one simulated year; longer simulations are not yet feasible. Superparameterizations have already been used in simulations longer than a century and have succeeded in simulating the Madden-Julian Oscillation, the diurnal cycle of precipitation, and other phenomena that have presented challenges for conventionally parameterized models.