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!Environment Canada - Atmospheric Science and Technology License/Disclaimer,
! version 3; Last Modified: May 7, 2008.
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SUBROUTINE LLINTV2 (PVLEV,PVI,PVIG,PPS,KNIDIM,KNI,
S KNPROF,KNO,PPO,PVO)
#if defined (DOC)
*
***s/r LLINTV2 - Tangent linear of linear interpolation and constant
* value extrapolation.
* Input pressure levels can vary for each profile.
*
*
*Author : J. Halle *CMDA/AES Oct 1999
*
*Revision 001 : J. Halle *CMDA/AES dec 2000
* adapt to TOVS level 1b.
*
*Revision 002 : JM Belanger *CMDA/SMC* june 2001
* 32 bits conversion.
*
*Revision 003 : J Halle *CMDA/SMC* april 2002
* corriger bug sur l'indice de vlev.
*
*Revision 004: J. Halle CMDA/SMC Feb 2003
* replace dynamic memory allocation with automatic arrays.
*Revision 005: P. Koclas CMDA/SMC Apr 2003
* -changed loop nesting order for ibm conversion
*Revision 006: C. Charette - ARMA/SMC - Sep. 2004
* Conversion to hybrid vertical coordinate
*Revision 007: J. Halle - CMDA/SMC - May 2005
* Bugfix for ps term; use vhybinc instead of vlev.
*
*Arguments
* i PVLEV(KNIDIM,KNPROF) : Vertical levels, pressure (source)
* i PVI(KNIDIM,KNPROF) : Vector to be interpolated (source) (gradients)
* i PVIG(KNIDIM,KNPROF) : Vector to be interpolated (source)
* i PPS(KNPROF) : Surface pressure (source) (gradients)
* i KNIDIM : Dimension of input levels (source)
* i KNI : Number of input levels (source)
* i KNPROF : Number of profiles
* i KNO : Number of output levels (destination)
* i PPO(KNO) : Vertical levels, pressure (destination)
* o PVO(KNO,KNPROF) : Interpolated profiles (destination)
*
* -------------------
** Purpose: Performs the tangent linear of the vertical interpolation
* in log of pressure and constant value extrapolation of
* one-dimensional vectors.
#endif
IMPLICIT NONE
*implicits
#include "pardim.cdk"
#include "comdim.cdk"
#include "comgem.cdk"
*
INTEGER JI, JK, JO, JN, IK, IORDER
INTEGER KNIDIM, KNI, KNO, KNPROF, ILEN, IERR
C
REAL*8 PVLEV(KNIDIM,KNPROF)
REAL*8 PPO(KNO), PVO(KNO,KNPROF)
REAL*8 PVI(KNIDIM,KNPROF)
REAL*8 PVIG(KNIDIM,KNPROF)
REAL*8 PPS(KNPROF)
C
REAL*8 ZPI (0:KNI+1,KNPROF)
REAL*8 ZPO (KNO ,KNPROF)
REAL*8 ZPVI (0:KNI+1,KNPROF)
REAL*8 ZPVIG(0:KNI+1,KNPROF)
REAL*8 ZVLEV(0:KNI+1)
INTEGER IL (KNO ,KNPROF)
C
REAL*8 ZW1, ZW2, ZDADPS, ZPRESBPB,ZPRESBPT
REAL*8 ZP, XI, ZRT, ZP1, ZP2
REAL*8 tmpv1
C
C** 0. Dynamic memory allocation for temporary vectors
C . -----------------------------------------------
C
050 CONTINUE
C
C ... removed and replaced by automatic arrays, jh feb 2003 ......
C
C** 1. Initialization for vertical extrapolation (extra dummy levels)
C . --------------------------------------------------------------
C
100 CONTINUE
C
DO JN = 1, KNPROF
ZPI(0 ,JN) = 2000.0
ZPI(KNI+1,JN) = 2000.0
ENDDO
C
C** 1.1 Determine if input pressure levels are in ascending or
C . descending order.
C . -------------------------------------------------------
C
IF ( PVLEV(1,1) .LT. PVLEV(KNI,1) ) THEN
IORDER = 1
ELSE
IORDER = -1
ENDIF
C
C** 2. Compute pressure levels pressure
C . ------------------------------------------------
C
200 CONTINUE
C
C** 2.1 Source levels
C . -------------
C
DO JN = 1, KNPROF
DO JK = 1, KNI
ZPI(JK,JN) = PVLEV(JK,JN)
ENDDO
ENDDO
C
C** 2.2 Destination levels
C . ------------------
C
DO JN = 1, KNPROF
DO JK = 1, KNO
ZPO(JK,JN) = PPO(JK)
ENDDO
ENDDO
C
C* 3. Interpolate in log of pressure or extrapolate with constant value
C* . for each destination pressure level
C . -----------------------------------------------------------------
C
300 CONTINUE
C
C
C* . 3.1 Find the adjacent level below
C . -----------------------------
C
310 CONTINUE
C
DO JN = 1, KNPROF
DO JO=1,KNO
IL(JO,JN) = 0
ENDDO
ENDDO
Cpiok
DO JI=1,KNI
DO JN = 1, KNPROF
DO JO=1,KNO
ZRT = ZPO(JO,JN)
ZP = ZPI(JI,JN)
XI = SIGN(1.0D0,IORDER*(ZRT-ZP))
IL(JO,JN) = IL(JO,JN) + MAX(0.0D0,XI)
ENDDO
ENDDO
ENDDO
C
C
C* . 3.2 Fill extra levels, for constant value extrapolation
C . ---------------------------------------------------
C
320 CONTINUE
Cpik
DO JN = 1, KNPROF
DO JK = 1, KNI
ZVLEV (JK) = VHYBINC (JK)
ZPVI (JK,JN) = PVI (JK,JN)
ZPVIG(JK,JN) = PVIG(JK,JN)
ENDDO
ENDDO
C
ZVLEV (0 ) = VHYBINC (1 )
ZVLEV (KNI+1) = VHYBINC (KNI)
DO JN = 1, KNPROF
ZPVI (0 ,JN) = PVI (1 ,JN)
ZPVI (KNI+1,JN) = PVI (KNI,JN)
ZPVIG(0 ,JN) = PVIG(1 ,JN)
ZPVIG(KNI+1,JN) = PVIG(KNI,JN)
ENDDO
C
C
C* . 3.3 Interpolation/extrapolation
C . ---------------------------
C
330 CONTINUE
Cpik
tmpv1 = rptopinc/rprefinc
DO JO=1,KNO
DO JN = 1, KNPROF
IK = IL(JO,JN)
ZP = ZPO(JO,JN)
ZP1 = ZPI(IK ,JN)
ZP2 = ZPI(IK+1,JN)
ZW1 = LOG(ZP/ZP2)/LOG(ZP1/ZP2)
ZW2 = 1. - ZW1
zpresbpt = ((zvlev(ik) - tmpv1) /(1.0-tmpv1))**rcoefinc
zpresbpb = ((zvlev(ik+1) - tmpv1)/(1.0-tmpv1))**rcoefinc
ZDADPS = ( (ZPRESBPT/ZP1)*LOG(ZP/ZP2)
+ -(ZPRESBPB/ZP2)*LOG(ZP/ZP1) )
+ /LOG(ZP2/ZP1)**2
PVO(JO,JN) = ZW1*ZPVI(IK,JN) + ZW2*ZPVI(IK+1,JN) +
& (ZPVIG(IK+1,JN)-ZPVIG(IK,JN))*
& ZDADPS*PPS(JN)
ENDDO
ENDDO
C
C* 4. Deallocate memory
C . -----------------
C
400 CONTINUE
C
C ... removed and replaced by automatic arrays, jh feb 2003 ......
C
RETURN
END