What can we tune for the water fields?

  • RHcrit
    • Different value for every vertical level (range from 0.8 to 0.92)
    • Expect this to be reduced for N48
    • Impact: Reducing this increases the amount of cloud
    • Comment: I'm unclear whether I should be changing each level by 0.01, 0.1, or something else?
  • two_d_fsd_factor (the higher the number the more inhomogeneous the cloud in the grid-box is allowed to be)
    • Default is 1.5
    • The main tool for tuning radiation fluxes
    • Impact: Increasing this seems to increase the SW at the TOA.
  • cff_spread_rate (ice cloud spreading rate)
    • Default is 1E-5
    • Impact: Increasing this seems to increase the area of cloud
  • dbsdtbs_turb_0. Value of cloud erosion /s-1
    • Default is 1.5E-4
    • In N48 we've reduced this to 0.875E-4 (counter to Cyril's intuition)
    • Impact: Increasing this will reduce the cloud