NSSL Options Prior to V4.6.0

In WRFV4.6.0, the NSSL microphysics schemes were all updated. If using an older version and wanting to use an NSSL option, see the following descriptions.

Scheme	Option	Mass Variables	Number Variables
NSSL 2-mom	17	Qc Qr Qi Qs Qg Qh	Nc Nr Ni Ns Ng Nh
NSSL 2-mom+CCN	18	Qc Qr Qi Qs Qg Qh	Nc Nr Ni Ns Ng Nh Nn
NSSL 7-class	19	Qc Qr Qi Qs Qg Qh	Vg
NSSL 6-class	21	Qc Qr Qi Qs Qg	N/A
NSSL 6-class 2-mom	22	Qc Qr Qi Qs Qg	Nn Nc Nr Ni Ns Ng Vg

Microphysics Option Details and References

Note : For NSSL single-moment schemes (options 19 and 21), intercept and particle densities can be set for snow, graupel, hail, and rain. For the single- and double-moment schemes (options 17,18, 19, 21, and 22), shape parameters for graupel and hail can be set (in the &physics section of namelist.input).*

nssl_alphah=0. : shape parameter for graupel nssl_alphahl=2. : shape parameter for hail nssl_cnoh=.e5 : graupel intercept nssl_cnohl=4.e4 : hail intercept nssl_cnor=8.e5 : rain intercept nssl_cnos=3.e6 : snow intercept nssl_rho_qh=500. : graupel density nssl_rho_qhl=900. : hail density nssl_rho_qs=100. : snow density

NSSL Double-moment mp_physics=17
Two-moment scheme for cloud droplets, rain drops, ice crystals, snow, graupel, and hail; also predicts average graupel particle density, which allows graupel to span the range from frozen drops to low-density graupel
Mansell et al., 2010

NSSL Double-moment with CCN prediction
mp_physics=18
3-moment bulk microphysics scheme for cloud droplets, rain drops, ice crystals, snow, graupel, and hail. It also predicts cloud condensation nuclei (CCN) concentration (intended for idealized simulations); intended for cloud-resolving simulations (dx <= 2km) in research applications. It provides accurate size-sorting of fast-falling hydrometers by effectively predicting the shape parameter of the gamma function particle size distribution.
Mansell et al., 2010

• To set global CCN value, use “nssl_cccn=0.7e9,” which also sets the same value for “ccn_conc”

• See WRF/doc/README.NSSLmp for additional details.

NSSL Single-moment 7-class mp_physics=19
A single-moment version of option 17 (above)
No publication available

NSSL single-moment 6-class mp_physics=21
Intended for cloud-resolving simulations (dx <= 2km) in research applications; similar to
Gilmore et al. (2004)

NSSL Double-moment with Graupel mp_physics=22
Similar to option 17 (above), without hail
No publication available