VLab Issue #68141

    modified:   docs/FV3_citations.bib
    modified:   model/fv_cmp.F90

    1) Add an option (namelist parameter: intqs) to use temperature instead of the liquid frozen
    temperature to calculate saturation mixing ratio in deriving GFDLMP PDF cloud cover.
    2) Add a literature reference.

docs/FV3_citations.bib

@@ -33,6 +33,16 @@ @article{chen2013seasonal
  doi={10.1175/JCLI-D-12-00061.1}
 }
 
+@article{zhou2019toward,
+ title={Toward Convective-Scale Prediction within the Next Generation Global Prediction System},
+ author={Zhou, Linjiong and Lin, Shian-Jiann and Chen, Jan-Huey and Harris, Lucas M. and Chen, Xi and Rees, Shannon L.},
+ journal={Bulletin of the American Meteorological Society},
+ volume={100},
+ issue={7},
+ year={2019},
+ doi={10.1175/bams-d-17-0246.1}
+}
+
 @article {deng2008cirrus,
 author = {Deng, Min and Mace, Gerald G.},
 title = {Cirrus cloud microphysical properties and air motion statistics using cloud radar Doppler moments: Water content, particle size, and sedimentation relationships},

model/fv_cmp.F90

@@ -50,7 +50,7 @@ module fv_cmp_mod
 ! <td>gfdl_cloud_microphys_mod</td>
 ! <td>ql_gen, qi_gen, qi0_max, ql_mlt, ql0_max, qi_lim, qs_mlt,
 ! tau_r2g, tau_smlt, tau_i2s, tau_v2l, tau_l2v, tau_imlt, tau_l2r,
-! rad_rain, rad_snow, rad_graupel, dw_ocean, dw_land</td>
+! rad_rain, rad_snow, rad_graupel, dw_ocean, dw_land, tintqs</td>
 ! </tr>
 ! </table>
 
@@ -60,7 +60,7 @@ module fv_cmp_mod
  use gfdl_cloud_microphys_mod, only: ql_gen, qi_gen, qi0_max, ql_mlt, ql0_max, qi_lim, qs_mlt
  use gfdl_cloud_microphys_mod, only: icloud_f, sat_adj0, t_sub, cld_min
  use gfdl_cloud_microphys_mod, only: tau_r2g, tau_smlt, tau_i2s, tau_v2l, tau_l2v, tau_imlt, tau_l2r
- use gfdl_cloud_microphys_mod, only: rad_rain, rad_snow, rad_graupel, dw_ocean, dw_land
+ use gfdl_cloud_microphys_mod, only: rad_rain, rad_snow, rad_graupel, dw_ocean, dw_land, tintqs
 #ifdef MULTI_GASES
  use multi_gases_mod, only: virq_qpz, vicpqd_qpz, vicvqd_qpz, num_gas
 #endif
@@ -774,9 +774,14 @@ subroutine fv_sat_adj (mdt, zvir, is, ie, js, je, ng, hydrostatic, consv_te, te0
 
  do i = is, ie
 
- tin = pt1 (i) - (lcp2 (i) * q_cond (i) + icp2 (i) * q_sol (i)) ! minimum temperature
+ if(tintqs) then 
+ tin = pt1(i)
+ else 
+! tin = pt1 (i) - (lcp2 (i) * q_cond (i) + icp2 (i) * q_sol (i)) ! minimum temperature
+ tin = pt1 (i) - (lcp2 (i) * q_liq (i) + icp2 (i) * q_sol (i)) ! minimum temperature
  ! tin = pt1 (i) - ((lv00 + d0_vap * pt1 (i)) * q_cond (i) + &
  ! (li00 + dc_ice * pt1 (i)) * q_sol (i)) / (mc_air (i) + qpz (i) * c_vap)
+ endif 
 
  ! -----------------------------------------------------------------------
  ! determine saturated specific humidity
@@ -820,14 +825,14 @@ subroutine fv_sat_adj (mdt, zvir, is, ie, js, je, ng, hydrostatic, consv_te, te0
  ! icloud_f = 2: binary cloud scheme (0 / 1)
  ! -----------------------------------------------------------------------
 
- if (rh > 0.75 .and. qpz (i) > 1.e-6) then
+ if (rh > 0.75 .and. qpz (i) > 1.e-8) then
  dq = hvar (i) * qpz (i)
  q_plus = qpz (i) + dq
  q_minus = qpz (i) - dq
  if (icloud_f == 2) then
  if (qpz (i) > qstar (i)) then
  qa (i, j) = 1.
- elseif (qstar (i) < q_plus .and. q_cond (i) > 1.e-6) then
+ elseif (qstar (i) < q_plus .and. q_cond (i) > 1.e-8) then
  qa (i, j) = ((q_plus - qstar (i)) / dq) ** 2
  qa (i, j) = min (1., qa (i, j))
  else
@@ -847,7 +852,7 @@ subroutine fv_sat_adj (mdt, zvir, is, ie, js, je, ng, hydrostatic, consv_te, te0
  qa (i, j) = 0.
  endif
  ! impose minimum cloudiness if substantial q_cond (i) exist
- if (q_cond (i) > 1.e-6) then
+ if (q_cond (i) > 1.e-8) then
  qa (i, j) = max (cld_min, qa (i, j))
  endif
  qa (i, j) = min (1., qa (i, j))