| 1 |
C $Header: /u/gcmpack/MITgcm/pkg/aim_v23/phy_lscond.F,v 1.2 2006/01/26 01:14:11 jmc Exp $ |
| 2 |
C $Name: $ |
| 3 |
|
| 4 |
#include "AIM_OPTIONS.h" |
| 5 |
|
| 6 |
SUBROUTINE LSCOND (PSA,dpFac,QA,QSAT, |
| 7 |
O PRECLS,DTLSC,DQLSC, |
| 8 |
I kGrd,bi,bj,myThid) |
| 9 |
C-- |
| 10 |
C-- SUBROUTINE LSCOND (PSA,QA,QSAT, |
| 11 |
C-- * PRECLS,DTLSC,DQLSC) |
| 12 |
C-- |
| 13 |
C-- Purpose: Compute large-scale precipitation and |
| 14 |
C-- associated tendencies of temperature and moisture |
| 15 |
C-- Input: PSA = norm. surface pressure [p/p0] (2-dim) |
| 16 |
C dpFac = cell delta_P fraction (3-dim) |
| 17 |
C-- QA = specific humidity [g/kg] (3-dim) |
| 18 |
C-- QSAT = saturation spec. hum. [g/kg] (3-dim) |
| 19 |
C-- Output: PRECLS = large-scale precipitation [g/(m^2 s)] (2-dim) |
| 20 |
C-- DTLSC = temperature tendency from l.s. cond (3-dim) |
| 21 |
C-- DQLSC = hum. tendency [g/(kg s)] from l.s. cond (3-dim) |
| 22 |
C Input: kGrd = Ground level index (2-dim) |
| 23 |
C bi,bj = tile index |
| 24 |
C myThid = Thread number for this instance of the routine |
| 25 |
C-- |
| 26 |
|
| 27 |
IMPLICIT NONE |
| 28 |
|
| 29 |
C Resolution parameters |
| 30 |
|
| 31 |
C-- size for MITgcm & Physics package : |
| 32 |
#include "AIM_SIZE.h" |
| 33 |
|
| 34 |
#include "EEPARAMS.h" |
| 35 |
|
| 36 |
C Physical constants + functions of sigma and latitude |
| 37 |
|
| 38 |
#include "com_physcon.h" |
| 39 |
|
| 40 |
C Large-scale condensation constants |
| 41 |
|
| 42 |
#include "com_lsccon.h" |
| 43 |
|
| 44 |
C-- Routine arguments: |
| 45 |
_RL PSA(NGP), dpFac(NGP,NLEV), QA(NGP,NLEV), QSAT(NGP,NLEV) |
| 46 |
_RL PRECLS(NGP), DTLSC(NGP,NLEV), DQLSC(NGP,NLEV) |
| 47 |
INTEGER kGrd(NGP) |
| 48 |
INTEGER bi,bj,myThid |
| 49 |
|
| 50 |
#ifdef ALLOW_AIM |
| 51 |
|
| 52 |
C-- Local variables: |
| 53 |
INTEGER J, K |
| 54 |
_RL PSA2(NGP) |
| 55 |
|
| 56 |
C- jmc: declare all local variables: |
| 57 |
_RL RTLSC, TFACT, PRG |
| 58 |
_RL SIG2, RHREF, DQMAX, PFACT |
| 59 |
C---+----1----+----2----+----3----+----4----+----5----+----6----+----7-|--+----| |
| 60 |
|
| 61 |
C-- 1. Initialization |
| 62 |
|
| 63 |
c_FM QSMAX = 50. |
| 64 |
|
| 65 |
RTLSC = 1./(TRLSC*3600.) |
| 66 |
TFACT = ALHC/CP |
| 67 |
PRG = P0/GG |
| 68 |
|
| 69 |
DO J=1,NGP |
| 70 |
DTLSC(J,1) = 0. |
| 71 |
DQLSC(J,1) = 0. |
| 72 |
PRECLS(J) = 0. |
| 73 |
PSA2(J) = PSA(J)*PSA(J) |
| 74 |
ENDDO |
| 75 |
|
| 76 |
C-- 2. Tendencies of temperature and moisture |
| 77 |
C NB. A maximum heating rate is imposed to avoid |
| 78 |
C grid-point-storm instability |
| 79 |
|
| 80 |
DO K=2,NLEV |
| 81 |
SIG2=SIG(K)*SIG(K) |
| 82 |
c_FM RHREF = RHLSC+DRHLSC*(SIG2-1.) |
| 83 |
c_FM DQMAX = (1.1-RHREF)*QSMAX*SIG2*RTLSC |
| 84 |
DO J=1,NGP |
| 85 |
RHREF = RHLSC+DRHLSC*(SIG2/PSA2(J) - 1. _d 0) |
| 86 |
DQMAX = (1.1 _d 0-RHREF)*QSMAX*SIG2*RTLSC |
| 87 |
DQLSC(J,K) = MIN(0. _d 0,(RHREF*QSAT(J,K)-QA(J,K)))*RTLSC |
| 88 |
c_FM DTLSC(J,K) = TFACT*MIN(-DQLSC(J,K),DQMAX*PSA2(J)) |
| 89 |
c DTLSC(J,K) = TFACT*MIN(-DQLSC(J,K),DQMAX) |
| 90 |
C-jmc: the threshold on latent heat (above) breaks the energy conservation; |
| 91 |
C to fix this, apply the threshold directly to the condensation |
| 92 |
DQLSC(J,K) = MAX(-DQMAX, DQLSC(J,K) ) |
| 93 |
DTLSC(J,K) = -TFACT*DQLSC(J,K) |
| 94 |
ENDDO |
| 95 |
ENDDO |
| 96 |
|
| 97 |
C-- Scale LSC tendencies by dpFac (=Partial-Cell factor) (=> Mass Weighted) |
| 98 |
C to get homogenous units & scaling across all physics tendencies. |
| 99 |
DO K=2,NLEV |
| 100 |
DO J=1,NGP |
| 101 |
DQLSC(J,K) = DQLSC(J,K)*dpFac(J,K) |
| 102 |
DTLSC(J,K) = DTLSC(J,K)*dpFac(J,K) |
| 103 |
ENDDO |
| 104 |
ENDDO |
| 105 |
|
| 106 |
C-- 3. Large-scale precipitation |
| 107 |
|
| 108 |
DO J=1,NGP |
| 109 |
DO K=2,kGrd(J) |
| 110 |
PFACT = DSIG(K)*PRG |
| 111 |
PRECLS(J) = PRECLS(J)-PFACT*DQLSC(J,K) |
| 112 |
ENDDO |
| 113 |
ENDDO |
| 114 |
|
| 115 |
c_FM DO J=1,NGP |
| 116 |
c_FM PRECLS(J) = PRECLS(J)*PSA(J) |
| 117 |
c_FM ENDDO |
| 118 |
|
| 119 |
C-- |
| 120 |
#endif /* ALLOW_AIM */ |
| 121 |
|
| 122 |
RETURN |
| 123 |
END |
Parent Directory
| 
Revision Log
| 
Revision Graph