THE RELATION BETWEEN MOIST CONVECTIVE ADJUSTMENT SCHEMES AND THE MASS-FLUX CONCEPT FOR CUMULUS PARAMETERIZATION

The problem of finding convective mass fluxes and convective condensat ion rates in moist convective adjustment schemes for cumulus parameter ization in numerical weather prediction is addressed. Formal considera tions reveal that, in general, it is impossible to directly subdivide convective adjustment increments, invoked by the particular reference profile imposed, into contributions from vertical convective transport s and condensation in convective clouds. Furthermore, there does not e xist, in general, a unique vertical mass-flux profile, which would con sistently account for the increments of the various thermodynamic and water variables to be adjusted.