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Difference of parameters between f05_f05 and f09_f09 in cam.buildnml.csh of the CAM5.1 AGCM setup

hch081@uib_no

New Member
Hello,The following parameters are different in cam.buildnml.csh of the CAM5.1 AGCM setup:           f09×f09                                                                                    f05×f05                                                cldwat_icritc  =  18.0e-6                                                            cldwat_icritc  =  45.0e-6    div24del2flag  =  4                                                                    div24del2flag  = 42          nspltvrm  = 1                                                                            nspltvrm  = 2       hkconv_c0  =   1.0e-4                                                                hkconv_c0  =   5.0e-5When I check the CAM Namelist Variables, I got the following information:cldwat_icritic: Threshold for autoconversion of cold ice in RK microphysics scheme.
div24del2flag: Chooses type of divergence damping and velocity diffusion.div24del2flag = 2 for ldiv2 (default),
= 4 for ldiv4,
= 42 for ldiv4 + ldel2
where
ldiv2: 2nd-order divergence damping everywhere and increasing in top layers
ldiv4: 4th-order divergence damping
ldel2: 2nd-order velocity-component damping targetted to top layers,
with coefficient del2coef

Default: set by build-namelistnspltvrm: Number of vertical re-mapping timesteps per physics timestep.Nspltrac is partitioned into nspltvrm and nspltrac/nspltvrm,
with the latter being the number of tracer timesteps per
re-mapping timestep, possibly rounded upward; after initialization,
the code quantity nspltrac is redefined to be the number of
tracer timesteps per re-mapping timestep.
Default: 0hkconv_c0: Rain water autoconversion coefficient for Hack shallow scheme.Default: set by build-namelistDoes it mean the parameterization is different in the two resolutions?Also, do I need to change these parameters before the experiment start?Thank you very much!Hoffman   
 
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