Precipitation and other microphysical processes Radiatively active

							Precipitation and other microphysical processes
Radiatively active clouds
Convection
Turbulence
Gravity waves
Chemical processes

Scale dependence
       At a point, everything is simple.
              Continuum approximation
              Motion, thermodynamics
              Thermodynamic equilibrium holds.
       Averaging smooths things out.
              Averaging length is not necessarily the grid size
       Nevertheless, when we average, things get complicated.
              Motion, thermodynamics
              Thermodynamic equilibrium does not apply to the averaged state.

What averaged fields are we interested in?
      States
             Temperature
             Water vapor
             Horizontal wind vector
      Rates
             Precipitation
             Radiation
             Convective and turbulent fluxes of sensible heat, moisture, and momentum

Things that happen when you average
       Mean liquid water positive even though the mean RH is less than 100%
       Fractional cloudiness
       Fluxes due to scales smaller than the averaging length

What is parameterization?
       Needed in both numerical and analytical models
       Not just an engineering exercise -- not just a means to an end
       Not made obsolete by infinitely powerful computers

Compare parameterizations for geophysics and engineering. Do physicists parameterize? What
does it mean to "explain" something?

Kinetic theory of ideal gases --> Ideal Gas Law

Specific parameterizations
       Deep convection
              Moist convective adjustment
               Arakawa-Schubert
               Kane-Fritsch
               Emanuel
                       For analytical models
                       For numerical models
       Stratiform clouds
               Smagorinsky
               Sundqvist
               Tiedtke
       PBL
               Deardorff
               Lilly
               Mellor-Yamada and follow-ons
               Lappen-Randall
       Shallow convection
               Betts
               Tiedtke
               Bretherton
       Super-parameterization
               First-generation
               Second-generation

Friction
        under-studied problem

Horizontal diffusion
       under-studied problem

Numerics and parameterizations
      under-studied problem

Testing parameterizations
       GATE and other early experiments
       ARM and GCSS