In ARW the default schemes in namelist.input for e.g. physics are:
mp_physics = 3, 3, 3,
ra_lw_physics = 1, 1, 1,
ra_sw_physics = 1, 1, 1,
radt = 30, 30, 30,
sf_sfclay_physics = 1, 1, 1,
sf_surface_physics = 2, 2, 2,
bl_pbl_physics = 1, 1, 1,
bldt = 0, 0, 0,
cu_physics = 1, 1, 0,
cudt = 5, 5, 5,
isfflx = 1,
ifsnow = 1,
icloud = 1,
surface_input_source = 1,
num_soil_layers = 4,
sf_urban_physics = 0, 0, 0,
Nevertheless, there are million combinations of schemes. Which are better for storms?
George I do not have much knowledge to help you but for the Greek area studies about cumulus physics scheme by Lagouvardos, Kotroni, Sintosi, Bartzokas etc suggest Kain-Fritsch scheme.
Mazarakis, N., V. Kotroni, K. Lagouvardos, A.A. Argiriou, and C.J. Anderson, 2011: The
sensitivity of warm period precipitation forecasts to various modifications of the
Kain – Fritch Convective Parameterization Scheme. Natural Hazards and Earth
System Science,s 11, 1327-1339.
http://forecast.uoa.gr/greek/publications.php
http://www.jourlib.org/paper/1377522#.VImMgjGUeow
Hi George,
You probably need to conduct some empirical testing to figure out suitable combinations. Perhaps starting from some 'known-to-work' combinations from literature for storms in your specific area of interest. The search space is just too huge, so you probably want to first concentrate on those physical processes that most affected the storms at your area. I think after some test run, you should quickly figure out which processes the storm is less sensitive to.
Hope this helps.
Hi all,
As others colleagues said, the spatial resolution you use is key to set these parameters. It is recommended, for instance, to use the same microphysics scheme for all your domains (this is imperative if you are running a two-way nested simulation or an online one-way run).
If the inner domain has a grid spacing of 5-3 km or less, maybe you should switch off the cumulus parameterization to leave the model resolve explicitly the storms. In this case, however, using a microphysics scheme with graupel (such as WSM6 or Thompson) is desirable.
Again, as others colleagues said, the best way to proceed is to conduct several experiments (you may choose 1 or 2 cases) and, usually, you'll quickly figure out the physical schemes that you should avoid.
And finally, if you're running the WRF v3.6, you might try the Grell-Freitas scheme even for the higher resolution domain... It was designed to be used on this "grey zone" for the convective schemes.
Good luck!
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