Is COMBLE-MIP only for LES and SCM models with two-moment microphysics schemes?

[fridlind]

The design of the experiment seems intended for the use of double-moment microphysics schemes, especially Part II. Single-moment schemes do not provide prognostic droplet and ice/snow crystal number concentrations. Does it mean that also for Part I for the final commit of results we also need to use the double-moment scheme? Does it also mean that the double-moment scheme has the be used in SCM models? I would expect that this condition might limit the number of participating SCM models.

[fridlind]

Short answer: no, COMBLE-MIP is designed for partial participation, depending upon participating model capabilities. We plan to compare models and observations within Part I and Part II in separate manuscripts. We expect that model/scheme combinations that cannot fix droplet number concentration (e.g., LES with a bin microphysics or Lagrangian particle tracking scheme) would submit only to Part II. SCM models with fully interactive aerosol or detailed convective microphysics schemes may also be rare. We hope to include all LES and SCM submissions to Part I and Part II, including those that cannot fully implement the specifications (e.g., an SCM submission to Part II that includes prognostic aerosol only in the stratiform scheme but not the convective scheme). However, we reserve the possibility that we may be unable to accommodate all submissions that do not comply with specifications in the manuscripts, depending on number of participants and manuscript length.