EAMXX: User control over the are four factors that control in cloud and below cloud activation.

[overfelt]

sol_factb_below_cloud -below-cloud scavenging fraction is basically a tuning factor.
sol_facti_cloud_borne - in-cloud scavenging fraction has a physical basis and reflects activation fraction.
sol_factic_cloud_borne - in-cloud convective scavenging fraction has a physical basis and reflects activation fraction
f_act_conv_below_cloud - convection activation fraction.

The defaults are the same as have always been used so this is a BFB change:

[BFB]

[mahf708]

incomplete, gotta add those new params in the xml file under the appropriate process

[mahf708]

@overfelt how do you feel about adding better names for the user-facing tuning knobs? Something clearer than the sol f act etc?

[overfelt]

I asked @singhbalwinder to come up with better names. It is further complicated as these are not directly used, but inputs to the function that calculates the factors.

[rljacob]

waiting on changes from @singhbalwinder

[rljacob]

@singhbalwinder this needs your attention.

[singhbalwinder]

@overfelt : Could you please use the following variable names (suggested by @kaizhangpnl ):

1. sol_factb_below_cloud (new name: scav_fraction_below_cloud_strat): below-cloud scavenging fraction is basically a tuning factor.
 
2. sol_facti_cloud_borne (new name: scav_fraction_in_cloud_strat): in-cloud scavenging fraction has a physical basis and reflects activation fraction.

3. sol_factic_cloud_borne (new name: scav_fraction_in_cloud_conv): in-cloud convective scavenging fraction has a physical basis and reflects activation fraction

4. f_act_conv_below_cloud (new name: activation_fraction_in_cloud_conv) : convection activation fraction.