Increase convective scavenging for accumulation and coarse mode sea-salt and potentially sulphate from aqueous phase chemistry

[oyvindseland]

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

Convective in-cloud scavenging scavenging coefficients (soluble fraction and activation fraction) in NorESM2 are the same for all mixtures (0.8x0.4) This was supposed to varied between the mixtures but was lost in other development work. Both for physical reasons and based on high sea-salt aerosol optical depth in the model the scavenging coefficient for coarse and accumulation mode sea-salt should be 1. The physical interpretation is that all accumulation mode and coarse mode sea-salt particles are activated at cloud base in convective clouds. An earlier experiment also included aqueous phase sulphate but I suggest that this waits until a potential re-tuning of all mixture values. Ideally this should be implemented as a value for each tracer but can be done for only for the relevant tracer as found in oyvindseland@2a92af6

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

No response

Will this change (regression test) answers?

Yes

Will you be implementing this enhancement yourself?

Yes

[oyvindseland]

Works in test and expect to send a pull request soon. Preferably the values should be added for all tracers rather than adding only 3 indices. This is similar to how below cloud scavenging coefficients are added. It is a lower priority though

[oyvindseland]

Identical to issue #12 for Oslo-Aero. Closing this issue

[oyvindseland]

I think this should also go into 2.5. How should I best do so. Open a separate issue for 2.5 and creating a pull request for the relevant file. @mvertens