Ball-Berry parameters in CLM5.0 should go back to the previous values in CLM4.5

[ekluzek]

Gordon Bonan brings this up. The Ball-Berry parameters were adjusted in an attempt to tune CLM5.0, and the tuning wasn't satisfactory. The satisfactory tuning involved the new Medlyn photosynthesis. So if you use Ball-Berry in CLM5.0 you should use the previous values rather than the new ones.

[billsacks]

My understanding (without looking carefully) is that this impacts cases that use clm50 physics but manually change to using Ball-Berry, or turn PHS off (which also causes you to revert to Ball-Berry); this also impacts the new NWP configuration, which uses Ball-Berry by default.

Since clm4.5 uses a different params file, I'm guessing that is not affected, but I haven't actually checked that myself.

[ekluzek]

CLM4.0 had: 9, 6, 6, 6, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 5, 9, 9, 4, 9, 9, 9
CLM4.5 has: 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 4, 9, 9, 4, 4, 9, 9 note 2nd-4th are 9 rather than 6, 15th is 4 rather than 5 and 19 is 4 rather than 9
CLM5.0 has: 9, 4.4713363873471, 7.10166797896943, 7.10166797896943,
7.29147600379525, 7.10166797896943, 7.1797077457757, 7.10166797896943,
7.10166797896943, 7.10166797896943, 7.10166797896943, 7.10166797896943,
7.10166797896943, 9.75753228727652, 9.75753228727652, 9.75753228727652,
9, 4, 4, 9, 9

(So first and last five are the same as CLM4.5)

[ekluzek]

Gordon Bonan replies on this that the CLM4.5 values should be used

"Thanks for following up on this. The correct values to use for mbbopt are those from CLM4.5. There are only two unique values: 9 for C3 plants and 4 for C4 plants."