What to do if there are two identical quantities from different schemes/processes that need to be kept apart?

[climbfuji]

NRL is working heavily on the high-altitude physics in NEPTUNE using CCPP. A question came up for which I don't have a good answer.

In the high-altitude configuration, there are two non-orographic gravity wave drag schemes active at the same time. The "ordinary" non-orographic GWD scheme from the "lower" atmosphere, and the high-altitude version from the high-altitude physics. Both are active at the same time, and the high-altitude version runs over the entire column, i.e. including the lower atmosphere where the ordinary scheme is active. It is necessary to keep the standard names for these quantities separate so that they can be treated as different tendencies in the tendencies array etc.

What do we do in this case? We were trying to find physically meaningful names. The qualifier "in_thermosphere", for example, doesn't make sense since the HA version runs over the entire column. Should we add a qualifier to the "due_to" descriptor? That is,

cumulative_change_of_x_wind_due_to_nonorographic_gravity_wave_drag
cumulative_change_of_x_wind_due_to_high_altitude_nonorographic_gravity_wave_drag

I am not sure I like this, because it somewhat still suggests that this is something in the upper atmosphere, but at least it allows for the interpretation that it can influence the lower atmosphere.

[matusmartini]

@climbfuji What about cumulative_change_of_x_wind_due_to_nonorographic_gravity_wave_drag_from_high_altitude_physics?

[mkavulich]

At today's framework meeting we discussed the potential of being more specific about "nonorographic". For example, if this is coming from magnetic high-altitude processes, can we call it cumulative_change_of_x_wind_due_to_magnetic_gravity_wave_drag?

[climbfuji]

At today's framework meeting we discussed the potential of being more specific about "nonorographic". For example, if this is coming from magnetic high-altitude processes, can we call it cumulative_change_of_x_wind_due_to_magnetic_gravity_wave_drag?

In this case, we would also replace the existing cumulative_change_of_x_wind_due_to_nonorographic_gravity_wave_drag with the actual physical process XYZ behind it: cumulative_change_of_x_wind_due_to_XYZ_gravity_wave_drag

[climbfuji]

Unfortunately, life is not so easy. I checked with the NRL developers, and the actual processes behind the non-orographic GWD from standard- and high-altitude physics are indeed the same or at least overlapping. We are trying to come up with something better.

cumulative_change_of_x_wind_due_to_convective_and_viscous_gravity_wave_drag

My gut feeling is that this is mixing qualifiers. "convective" refers to the wave source, while "viscous" refers to a wave dissipation mechanism (one of many).

[climbfuji]

From NRL:

What about something like

cumulative_change_of_x_wind_due_to_convective_whole_atmosphere_gravity_wave_drag

We keep "convective" because we are parameterizing waves generated by convection/frontogenesis in the lower atmosphere, as with the other scheme. Then we add the "whole atmosphere" qualifier to mean it is good from the ground to space ("high-altitude"). Alternatively, we put it at the end like

cumulative_change_of_x_wind_due_to_convective_gravity_wave_drag_in_whole_atmosphere

to mimic qualifiers like "in_stratosphere" or "in_thermosphere".

[mkavulich]

At today's meeting we decided the first suggestion (cumulative_change_of_x_wind_due_to_convective_whole_atmosphere_gravity_wave_drag) is preferred.

[dustinswales]

Hey @mdtoyNOAA. Do you have any thoughts on the GWD naming connevtions

[mdtoyNOAA]

Hey @mdtoyNOAA. Do you have any thoughts on the GWD naming connevtions

Holy cow! I didn't know there was a non-orographic GWD scheme that went even higher then the one in UGWP, which we've only tested up to the GFS top of ~80km. I guess the 'really high' scheme involves viscous dissipation that is active in the heterosphere above ~100km? This is beyond my expertise, so if it's okay, I won't add any naming suggestions. The ones that have been proposed sound good to me.