subroutine da_varbc_tl (cv_size, cv, iv, y) !--------------------------------------------------------------------------- ! PURPOSE: Apply bias correction to radiance innovations. ! ! METHOD: delta_d = y - delta_bc ! y = H (delta_x) ! delta_bc = SUM( delta_beta_i Pred_i ) ! i ! delta_beta = VarBC parameters ! Pred = Bias predictors ! ! Called from da_transform_vtoy ! ! HISTORY: 10/27/2007 - Creation Tom Auligne !--------------------------------------------------------------------------- implicit none integer, intent(in) :: cv_size ! Size of cv array. real, intent(in) :: cv(1:cv_size) ! control variables. type (iv_type), intent(in) :: iv ! O-B structure. type (y_type), intent(inout) :: y ! y = h (xa) integer :: inst, i, k, num_rad, n, npred real, allocatable :: varbc_param_tl(:) if (trace_use) call da_trace_entry("da_varbc_tl") do inst = 1, iv%num_inst ! loop for sensor num_rad = iv%instid(inst)%num_rad if (num_rad < 1) cycle allocate(varbc_param_tl(iv%instid(inst)%varbc_info%npredmax)) do k=1,iv%instid(inst)%nchan ! loop for channel npred = iv%instid(inst)%varbc(k)%npred if (npred <= 0) cycle ! VarBC channels only !--------------------------------------------------------------- ! Change of variable (preconditioning) !--------------------------------------------------------------- varbc_param_tl(:) = 0.0 do i = 1, npred varbc_param_tl(i) = SUM( cv(iv%instid(inst)%varbc(k)%index(1:npred)) * & iv%instid(inst)%varbc(k)%vtox(i,1:npred) ) end do !--------------------------------------------------------------- ! TL of bias correction through linear regression !--------------------------------------------------------------- do n = 1, num_rad ! loop for pixel if (iv%instid(inst)%tb_qc(k,n) <= qc_varbc_bad) cycle ! good obs only y%instid(inst)%tb(k,n) = y%instid(inst)%tb(k,n) + & SUM( varbc_param_tl(1:npred) * & iv%instid(inst)%varbc_info%pred( & iv%instid(inst)%varbc(k)%ipred(1:npred),n) ) end do end do deallocate(varbc_param_tl) end do ! end loop for sensor if (trace_use) call da_trace_exit("da_varbc_tl") end subroutine da_varbc_tl