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!
! CRTM_IRSSEM
!
! Module containing function to invoke the CRTM Infrared
! Sea Surface Emissivity Model (IRSSEM).
!
!
! CREATION HISTORY:
! Written by: Paul van Delst, 22-Jun-2005
! paul.vandelst@noaa.gov
!
<A NAME='CRTM_IRSSEM'><A href='../../html_code/crtm/CRTM_IRSSEM.f90.html#CRTM_IRSSEM' TARGET='top_target'><IMG SRC="../../gif/bar_purple.gif" border=0></A>
MODULE CRTM_IRSSEM 1,5
! -----------------
! Environment setup
! -----------------
! Module use
USE Type_Kinds
, ONLY: fp
USE Message_Handler, ONLY: SUCCESS, FAILURE, Display_Message
USE CRTM_Parameters, ONLY: ZERO, ONE, DEGREES_TO_RADIANS
USE CRTM_Interpolation, ONLY: NPTS, &
LPoly, &
LPoly_type, &
Clear_LPoly, &
Find_Index, &
Interp_3D, &
LPoly_TL, &
Interp_3D_TL, &
LPoly_AD, &
Interp_3D_AD
USE IRwaterCoeff_Define, ONLY: IRwaterCoeff_type
! Disable implicit typing
IMPLICIT NONE
! ------------
! Visibilities
! ------------
! Everything private by default
PRIVATE
! Derived type
PUBLIC :: iVar_type
! Procedures
PUBLIC :: CRTM_Compute_IRSSEM
PUBLIC :: CRTM_Compute_IRSSEM_TL
PUBLIC :: CRTM_Compute_IRSSEM_AD
! -----------------
! Module parameters
! -----------------
! Version Id for the module
CHARACTER(*), PARAMETER :: MODULE_VERSION_ID = &
'$Id: CRTM_IRSSEM.f90 29405 2013-06-20 20:19:52Z paul.vandelst@noaa.gov $'
! Message string length
INTEGER, PARAMETER :: ML = 256
! -------------------------------
! Structure definition to hold
! forward interpolating variables
! across fwd, tl and adjoint
! -------------------------------
! The interpolation routine structure
TYPE :: Einterp_type
! The dimensions
INTEGER :: n_Angles = 0
INTEGER :: n_Pts = 0
! Allocation indicator
LOGICAL :: Is_Allocated = .FALSE.
! The interpolating polynomials
TYPE(LPoly_type), ALLOCATABLE :: wlp(:) ! Angle
TYPE(LPoly_type) :: xlp ! Frequency
TYPE(LPoly_type) :: ylp ! Wind Speed
! The LUT interpolation indices
INTEGER, ALLOCATABLE :: i1(:), i2(:) ! Angle
INTEGER :: j1 , j2 ! Frequency
INTEGER :: k1 , k2 ! Wind Speed
! The LUT interpolation boundary check
LOGICAL, ALLOCATABLE :: a_outbound(:) ! Angle
LOGICAL :: f_outbound ! Frequency
LOGICAL :: v_outbound ! Wind Speed
! The interpolation input
REAL(fp), ALLOCATABLE :: a_int(:) ! Angle
REAL(fp) :: f_int ! Frequency
REAL(fp) :: v_int ! Wind Speed
! The data to be interpolated
REAL(fp), ALLOCATABLE :: a(:,:) ! Angle
REAL(fp), ALLOCATABLE :: f(:) ! Frequency
REAL(fp), ALLOCATABLE :: v(:) ! Wind Speed
END TYPE Einterp_type
! The main internal variable structure
TYPE :: iVar_type
PRIVATE
! The interpolation data
TYPE(Einterp_type) :: ei
END TYPE iVar_type
CONTAINS
!################################################################################
!################################################################################
!## ##
!## ## PUBLIC MODULE ROUTINES ## ##
!## ##
!################################################################################
!################################################################################
!--------------------------------------------------------------------------------
!:sdoc+:
!
! NAME:
! CRTM_Compute_IRSSEM
!
! PURPOSE:
! Function to compute the CRTM infrared sea surface emissivity (IRSSE)
! for input wind speed, frequency, and angles.
!
! CALLING SEQUENCE:
! Error_Status = CRTM_Compute_IRSSEM( IRwaterCoeff, &
! Wind_Speed , &
! Frequency , &
! Angle , &
! iVar , &
! Emissivity )
!
! INPUTS:
! IRwaterCoeff: Infrared water emissivity model coefficient object.
! Load the object with the coefficients for the emissivity
! model to use.
! UNITS: N/A
! TYPE: IRwaterCoeff_type
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN)
!
! Wind_Speed: Wind speed.
! UNITS: metres per second (m.s^-1)
! TYPE: REAL(fp)
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN)
!
! Frequency: Infrared frequency.
! UNITS: inverse centimetres (cm^-1)
! TYPE: REAL(fp)
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN)
!
! Angle: Surface zenith angle.
! UNITS: Degrees
! TYPE: REAL(fp)
! DIMENSION: Rank-1 (n_Angles)
! ATTRIBUTES: INTENT(IN)
!
! OUTPUTS:
! iVar: Structure containing internal variables required for
! subsequent tangent-linear or adjoint model calls.
! The contents of this structure are NOT accessible
! outside of this module.
! UNITS: N/A
! TYPE: iVar_type
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(OUT)
!
! Emissivity: Sea surface emissivities for the
! requested wind speed, frequency, and angles.
! UNITS: N/A
! TYPE: REAL(fp)
! DIMENSION: Same as input ANGLE argument.
! ATTRIBUTES: INTENT(OUT)
!
! FUNCTION RESULT:
! Error_Status: The return value is an integer defining the error status.
! The error codes are defined in the Message_Handler module.
! If == SUCCESS the computation was successful.
! == FAILURE an unrecoverable error occurred.
! UNITS: N/A
! TYPE: INTEGER
! DIMENSION: Scalar
!
!:sdoc-:
!--------------------------------------------------------------------------------
<A NAME='CRTM_COMPUTE_IRSSEM'><A href='../../html_code/crtm/CRTM_IRSSEM.f90.html#CRTM_COMPUTE_IRSSEM' TARGET='top_target'><IMG SRC="../../gif/bar_green.gif" border=0></A>
FUNCTION CRTM_Compute_IRSSEM( & 1,10
IRwaterCoeff, & ! Input model coefficients
Wind_Speed , & ! Input
Frequency , & ! Input
Angle , & ! Input
iVar , & ! Internal variable output
Emissivity ) & ! Output
RESULT( err_stat )
! Arguments
TYPE(IRwaterCoeff_type), INTENT(IN) :: IRwaterCoeff
REAL(fp) , INTENT(IN) :: Wind_Speed ! v
REAL(fp) , INTENT(IN) :: Frequency ! f
REAL(fp) , INTENT(IN) :: Angle(:) ! a
TYPE(iVar_type) , INTENT(OUT) :: iVar
REAL(fp) , INTENT(OUT) :: Emissivity(:)
! Function result
INTEGER :: err_stat
! Local parameters
CHARACTER(*), PARAMETER :: ROUTINE_NAME = 'CRTM_Compute_IRSSEM'
! Local variables
CHARACTER(ML) :: msg
INTEGER :: n_Angles, i
REAL(fp) :: sec_angle(SIZE(Angle))
! Set up
err_stat = SUCCESS
! ...Check dimensions
n_Angles = SIZE(Angle)
IF ( SIZE(Emissivity) /= n_Angles ) THEN
err_stat = FAILURE
msg = 'Input Angle and output Emissivity array dimensions inconsistent.'
CALL Display_Message( ROUTINE_NAME, msg, err_stat )
RETURN
END IF
! ...Allocate interpolation variable structure
CALL Einterp_Create( iVar%ei, NPTS, n_Angles )
IF ( .NOT. Einterp_Associated( iVar%ei ) ) THEN
err_stat = FAILURE
msg = 'Error allocating interpolation variable structure.'
CALL Display_Message( ROUTINE_NAME, msg, err_stat )
RETURN
END IF
! ...Convert angles to secants
sec_angle = ONE/COS(DEGREES_TO_RADIANS*Angle)
! Compute the wind speed interpolating polynomial
! ...Find the LUT indices and check if input is out of bounds
iVar%ei%v_int = Wind_Speed
CALL find_index(IRwaterCoeff%Wind_Speed, &
iVar%ei%v_int, iVar%ei%k1, iVar%ei%k2, iVar%ei%v_outbound)
iVar%ei%v = IRwaterCoeff%Wind_Speed(iVar%ei%k1:iVar%ei%k2)
! ...Compute the polynomial
CALL LPoly( iVar%ei%v , & ! Input
iVar%ei%v_int, & ! Input
iVar%ei%ylp ) ! Output
! Compute the frequency interpolating polynomial
! ...Find the LUT indices and check if input is out of bounds
iVar%ei%f_int = Frequency
CALL find_index(IRwaterCoeff%Frequency, &
iVar%ei%f_int, iVar%ei%j1, iVar%ei%j2, iVar%ei%f_outbound)
iVar%ei%f = IRwaterCoeff%Frequency(iVar%ei%j1:iVar%ei%j2)
! ...Compute the polynomial
CALL LPoly( iVar%ei%f , & ! Input
iVar%ei%f_int, & ! Input
iVar%ei%xlp ) ! Output
! Compute the angle interpolating polynomials
DO i = 1, n_Angles
! ...Find the LUT indices and check if input is out of bounds
iVar%ei%a_int(i) = ABS(Angle(i))
CALL find_index(IRwaterCoeff%Angle, &
iVar%ei%a_int(i), iVar%ei%i1(i), iVar%ei%i2(i), iVar%ei%a_outbound(i))
iVar%ei%a(:,i) = IRwaterCoeff%Angle(iVar%ei%i1(i):iVar%ei%i2(i))
!! Secant interpolation test
!iVar%ei%a_int(i) = sec_angle(i)
!CALL find_index(IRwaterCoeff%Secant_Angle, &
! iVar%ei%a_int(i), iVar%ei%i1(i), iVar%ei%i2(i), iVar%ei%a_outbound(i))
!iVar%ei%a(:,i) = IRwaterCoeff%Secant_Angle(iVar%ei%i1(i):iVar%ei%i2(i))
! ...Compute the polynomial
CALL LPoly( iVar%ei%a(:,i) , & ! Input
iVar%ei%a_int(i), & ! Input
iVar%ei%wlp(i) ) ! Output
! Compute the interpolated emissivity
CALL Interp_3D( IRwaterCoeff%Emissivity( iVar%ei%i1(i):iVar%ei%i2(i), &
iVar%ei%j1 :iVar%ei%j2 , &
iVar%ei%k1 :iVar%ei%k2 ), & ! Input
iVar%ei%wlp(i), & ! Input
iVar%ei%xlp , & ! Input
iVar%ei%ylp , & ! Input
Emissivity(i) ) ! Output
END DO
END FUNCTION CRTM_Compute_IRSSEM
!--------------------------------------------------------------------------------
!:sdoc+:
!
! NAME:
! CRTM_Compute_IRSSEM_TL
!
! PURPOSE:
! Function to compute the tangent-linear CRTM infrared sea surface
! emissivity (IRSSE) for input wind speed, frequency, and angles.
!
! This function must be called *after* the forward model function,
! CRTM_Compute_IRSSEM, has been called. The forward model function
! populates the internal variable structure argument, iVar.
!
! CALLING SEQUENCE:
! Error_Status = CRTM_Compute_IRSSEM_TL( IRwaterCoeff , &
! Wind_Speed_TL, &
! iVar , &
! Emissivity_TL )
! INPUTS:
! IRwaterCoeff: Infrared water emissivity model coefficient object.
! Load the object with the coefficients for the emissivity
! model to use.
! UNITS: N/A
! TYPE: IRwaterCoeff_type
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN)
!
! Wind_Speed_TL: The tangent-linear wind speed.
! UNITS: metres per second (m.s^-1)
! TYPE: REAL(fp)
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN)
!
! iVar: Structure containing internal variables required for
! subsequent tangent-linear or adjoint model calls.
! The contents of this structure are NOT accessible
! outside of this module.
! UNITS: N/A
! TYPE: iVar_type
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN)
!
! OUTPUTS:
! Emissivity_TL: Tangent-linear sea surface emissivity.
! UNITS: N/A
! TYPE: REAL(fp)
! DIMENSION: Rank-1 (n_Angles)
! ATTRIBUTES: INTENT(OUT)
!
! FUNCTION RESULT:
! Error_Status: The return value is an integer defining the error status.
! The error codes are defined in the Message_Handler module.
! If == SUCCESS the computation was successful.
! == FAILURE an unrecoverable error occurred.
! UNITS: N/A
! TYPE: INTEGER
! DIMENSION: Scalar
!
!:sdoc-:
!--------------------------------------------------------------------------------
<A NAME='CRTM_COMPUTE_IRSSEM_TL'><A href='../../html_code/crtm/CRTM_IRSSEM.f90.html#CRTM_COMPUTE_IRSSEM_TL' TARGET='top_target'><IMG SRC="../../gif/bar_green.gif" border=0></A>
FUNCTION CRTM_Compute_IRSSEM_TL( & 1,6
IRwaterCoeff , & ! Input model coefficients
Wind_Speed_TL, & ! Input
iVar , & ! Internal variable input
Emissivity_TL) & ! Output
RESULT( err_stat )
! Arguments
TYPE(IRwaterCoeff_type), INTENT(IN) :: IRwaterCoeff
REAL(fp) , INTENT(IN) :: Wind_Speed_TL
TYPE(iVar_type) , INTENT(IN) :: iVar
REAL(fp) , INTENT(OUT) :: Emissivity_TL(:)
! Function result
INTEGER :: err_stat
! Local parameters
CHARACTER(*), PARAMETER :: ROUTINE_NAME = 'CRTM_Compute_IRSSEM_TL'
! Local variables
CHARACTER(ML) :: msg
INTEGER :: i
REAL(fp) :: v_TL(NPTS)
REAL(fp) :: e_TL(NPTS,NPTS,NPTS)
TYPE(LPoly_Type) :: ylp_TL, xlp_TL, wlp_TL
! Set up
err_stat = SUCCESS
! ...Check internal variable allocation
IF ( .NOT. Einterp_Associated( iVar%ei ) ) THEN
err_stat = FAILURE
msg = 'Internal structure ei is not allocated'
CALL Display_Message( ROUTINE_NAME, msg, err_stat )
RETURN
END IF
! ...Check dimensions
IF ( SIZE( Emissivity_TL ) /= iVar%ei%n_Angles ) THEN
err_stat = FAILURE
msg = 'Input Emissivity_TL array dimensions inconsistent with number of angles.'
CALL Display_Message( ROUTINE_NAME, msg, err_stat )
RETURN
END IF
! ...No TL if wind speed is out of bounds
IF ( iVar%ei%v_outbound ) THEN
Emissivity_TL = ZERO
RETURN
END IF
! ...Initialise local TL variables
v_TL = ZERO
e_TL = ZERO
CALL Clear_LPoly(wlp_TL)
CALL Clear_LPoly(xlp_TL)
! Calculate the TL interpolating
! polynomials for wind speed
CALL LPoly_TL( iVar%ei%v, iVar%ei%v_int, & ! FWD Input
iVar%ei%ylp, & ! FWD Input
v_TL, Wind_Speed_TL, & ! TL Input
ylp_TL ) ! TL Output
! Begin loop over angles
DO i = 1, iVar%ei%n_Angles
! Perform interpolation
CALL interp_3D_TL(IRwaterCoeff%Emissivity(iVar%ei%i1(i):iVar%ei%i2(i), &
iVar%ei%j1 :iVar%ei%j2 , &
iVar%ei%k1 :iVar%ei%k2 ), & ! FWD Emissivity input
iVar%ei%wlp(i), & ! FWD polynomial input
iVar%ei%xlp , & ! FWD polynomial input
iVar%ei%ylp , & ! FWD polynomial input
e_TL, wlp_TL, xlp_TL, ylp_TL, & ! TL input
Emissivity_TL(i) ) ! Output
END DO
END FUNCTION CRTM_Compute_IRSSEM_TL
!--------------------------------------------------------------------------------
!:sdoc+:
!
! NAME:
! CRTM_Compute_IRSSEM_AD
!
! PURPOSE:
! Function to compute the adjoint of the CRTM infrared sea surface
! emissivity (IRSSE) for input wind speed, frequency, and angles.
!
! This function must be called *after* the forward model function,
! CRTM_Compute_IRSSEM, has been called. The forward model function
! populates the internal variable structure argument, iVar.
!
! CALLING SEQUENCE:
! Error_Status = CRTM_Compute_IRSSEM_AD( IRwaterCoeff , &
! Emissivity_AD, &
! iVar , &
! Wind_Speed_AD )
!
! INPUTS:
! IRwaterCoeff: Infrared water emissivity model coefficient object.
! Load the object with the coefficients for the emissivity
! model to use.
! UNITS: N/A
! TYPE: IRwaterCoeff_type
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN)
!
! Emissivity_AD: Adjoint sea surface emissivity.
! *** SET TO ZERO ON EXIT ***
! UNITS: N/A
! TYPE: REAL(fp)
! DIMENSION: Rank-1 (n_Angles)
! ATTRIBUTES: INTENT(IN OUT)
!
! iVar: Structure containing internal variables required for
! subsequent tangent-linear or adjoint model calls.
! The contents of this structure are NOT accessible
! outside of this module.
! UNITS: N/A
! TYPE: iVar_type
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN)
!
! OUTPUTS:
! Wind_Speed_AD: Adjoint wind speed.
! *** MUST HAVE VALUE ON ENTRY ***
! UNITS: per metres per second, (m.s^-1)^-1
! TYPE: REAL(fp)
! DIMENSION: Scalar
! ATTRIBUTES: INTENT(IN OUT)
!
! FUNCTION RESULT:
! Error_Status: The return value is an integer defining the error status.
! The error codes are defined in the Message_Handler module.
! If == SUCCESS the computation was successful.
! == FAILURE an unrecoverable error occurred.
! UNITS: N/A
! TYPE: INTEGER
! DIMENSION: Scalar
!
!:sdoc-:
!--------------------------------------------------------------------------------
<A NAME='CRTM_COMPUTE_IRSSEM_AD'><A href='../../html_code/crtm/CRTM_IRSSEM.f90.html#CRTM_COMPUTE_IRSSEM_AD' TARGET='top_target'><IMG SRC="../../gif/bar_green.gif" border=0></A>
FUNCTION CRTM_Compute_IRSSEM_AD( & 1,7
IRwaterCoeff , & ! Input model coefficients
Emissivity_AD, & ! Input
iVar , & ! Internal Variable Input
Wind_Speed_AD) & ! Output
RESULT( err_stat )
! Arguments
TYPE(IRwaterCoeff_type), INTENT(IN) :: IRwaterCoeff
REAL(fp) , INTENT(IN OUT) :: Emissivity_AD(:)
TYPE(iVar_type) , INTENT(IN) :: iVar
REAL(fp) , INTENT(IN OUT) :: Wind_Speed_AD
! Function result
INTEGER :: err_stat
! Local parameters
CHARACTER(*), PARAMETER :: ROUTINE_NAME = 'CRTM_Compute_IRSSEM_AD'
! Local variables
CHARACTER(ML) :: msg
INTEGER :: i
REAL(fp) :: e_AD(NPTS,NPTS,NPTS)
REAL(fp) :: v_AD(NPTS)
TYPE(LPoly_Type) :: wlp_AD, xlp_AD, ylp_AD
! Set Up
err_stat = SUCCESS
e_AD = ZERO
v_AD = ZERO
! ...Check internal variable allocation
IF ( .NOT. Einterp_Associated( iVar%ei ) ) THEN
err_stat = FAILURE
msg = 'Internal structure ei is not allocated'
CALL Display_Message( ROUTINE_NAME, msg, err_stat )
RETURN
END IF
! ...Check dimensions
IF ( SIZE(Emissivity_AD) /= iVar%ei%n_Angles ) THEN
err_stat = FAILURE
msg = 'Input Emissivity_AD array dimensions inconsistent with number of angles.'
CALL Display_Message( ROUTINE_NAME, msg, err_stat )
RETURN
END IF
! ...No AD if wind speed is out of bounds
IF ( iVar%ei%v_outbound ) THEN
Wind_Speed_AD = ZERO
RETURN
END IF
! ...Initialize local variables
CALL Clear_LPoly(wlp_AD)
CALL Clear_LPoly(xlp_AD)
CALL Clear_LPoly(ylp_AD)
! Loop over emissivity calculation angles
DO i = 1, iVar%ei%n_Angles
! Get the adjoint interpoalting polynomial for wind speed
CALL Interp_3D_AD(IRwaterCoeff%Emissivity( iVar%ei%i1(i):iVar%ei%i2(i), &
iVar%ei%j1 :iVar%ei%j2 , &
iVar%ei%k1 :iVar%ei%k2 ), & ! FWD Input
iVar%ei%wlp(i) , & ! FWD Input
iVar%ei%xlp , & ! FWD Input
iVar%ei%ylp , & ! FWD Input
Emissivity_AD(i), & ! AD Input
e_AD, wlp_AD, xlp_AD, ylp_AD ) ! AD Output
! Set adjoint emissivity to zero
Emissivity_AD(i) = ZERO
END DO
! Compute the wind speed adjoint
CALL Lpoly_AD(iVar%ei%v , & ! FWD Input
iVar%ei%v_int, & ! FWD Input
iVar%ei%ylp , & ! FWD Input
ylp_AD , & ! AD Input
v_AD , & ! AD Output
Wind_Speed_AD ) ! AD Output
END FUNCTION CRTM_Compute_IRSSEM_AD
!################################################################################
!################################################################################
!## ##
!## ## PRIVATE MODULE ROUTINES ## ##
!## ##
!################################################################################
!################################################################################
! ----------------------------------------------
! Procedures to manipulate the Einterp structure
! ----------------------------------------------
<A NAME='EINTERP_ASSOCIATED'><A href='../../html_code/crtm/CRTM_IRSSEM.f90.html#EINTERP_ASSOCIATED' TARGET='top_target'><IMG SRC="../../gif/bar_green.gif" border=0></A>
ELEMENTAL FUNCTION Einterp_Associated( ei ) RESULT( Status )
TYPE(Einterp_type), INTENT(IN) :: ei
LOGICAL :: Status
Status = ei%Is_Allocated
END FUNCTION Einterp_Associated
<A NAME='EINTERP_DESTROY'><A href='../../html_code/crtm/CRTM_IRSSEM.f90.html#EINTERP_DESTROY' TARGET='top_target'><IMG SRC="../../gif/bar_red.gif" border=0></A>
ELEMENTAL SUBROUTINE Einterp_Destroy( ei )
TYPE(Einterp_type), INTENT(OUT) :: ei
ei%n_Angles = 0
ei%n_Pts = 0
ei%Is_Allocated = .FALSE.
END SUBROUTINE Einterp_Destroy
<A NAME='EINTERP_CREATE'><A href='../../html_code/crtm/CRTM_IRSSEM.f90.html#EINTERP_CREATE' TARGET='top_target'><IMG SRC="../../gif/bar_red.gif" border=0></A>
ELEMENTAL SUBROUTINE Einterp_Create( ei, n_Pts, n_Angles ) 1
TYPE(Einterp_type), INTENT(OUT) :: ei
INTEGER, INTENT(IN) :: n_Pts
INTEGER, INTENT(IN) :: n_Angles
INTEGER :: alloc_stat
IF ( n_Pts < 1 .OR. n_Angles < 1 ) RETURN
ALLOCATE( ei%wlp(n_Angles) , &
ei%i1(n_Angles) , &
ei%i2(n_Angles) , &
ei%a_outbound(n_Angles), &
ei%a_int(n_Angles) , &
ei%a(n_Pts,n_Angles) , &
ei%f(n_Pts) , &
ei%v(n_Pts) , &
STAT = alloc_stat )
IF ( alloc_stat /= 0 ) RETURN
ei%n_Angles = n_Angles
ei%n_Pts = n_Pts
ei%Is_Allocated = .TRUE.
END SUBROUTINE Einterp_Create
END MODULE CRTM_IRSSEM