Add height dependence option to the ZM convection entrainment rate (dmpdz)

[swrneale]

What is the feature/what would you like to discuss?

Adding an option to make ZM deep convection test parcel entrainment rate have a simple linear dependence on height. An extra dmpdz_ut variable is added and a height transition region between the default lower troposphere value (still dmpdz) and this ut value. The default will have dmpdz=dmpdz_ut, effectively unchanged from the current constant everywhere value of dmpdz value.

Is there anyone in particular you want to be part of this conversation?

@JulioTBacmeister @adamrher

Will this change (regression test) answers?

Yes

Will you be implementing this enhancement yourself?

Yes

[swrneale]

@cacraigucar I am at cam6_4_089 with these mods currently and so will bring up to the cam_dev branch probably won't be until week of 11th Aug.