Rain_formation

Composed cloud microphysics model (Seinfeld & Pandis 2006, Ch. 17). Flat composition of CloudDynamics (adiabatic thermodynamics, LCL height), IcePhysics (freezing point depression, ice nuclei), RainFormation (collision-coalescence, raindrop spectra), and AerosolScavenging (scavenging ratios and coefficient). Shared physical constants M_w and R unify CloudDynamics and IcePhysics. Ice particle diameter (D_p_ice) and collector drop diameter (D_p_rain) are kept as independent parameters. Migrated from Aerosol.jl src/cloud_physics.jl:735 (esm-c8z).

Rain formation by collision and coalescence (Seinfeld & Pandis 2006, Eqs. 17.104-17.108). Computes collection efficiency, continuous accretion rate, and raindrop size distributions (Best CDF and Marshall-Palmer number density).