| 1 | subroutine radar_simulator( & |
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| 2 | hp, & |
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| 3 | nprof,ngate, & |
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| 4 | undef, & |
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| 5 | hgt_matrix,hm_matrix,re_matrix,Np_matrix, & |
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| 6 | p_matrix,t_matrix,rh_matrix, & |
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| 7 | Ze_non,Ze_ray,a_to_vol,g_to_vol,dBZe, & |
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| 8 | g_to_vol_in,g_to_vol_out) |
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| 9 | |
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| 10 | use m_mrgrnk |
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| 11 | use array_lib |
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| 12 | use math_lib |
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| 13 | use optics_lib |
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| 14 | use radar_simulator_types |
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| 15 | use scale_LUTs_io |
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| 16 | implicit none |
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| 17 | |
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| 18 | ! Purpose: |
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| 19 | ! |
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| 20 | ! Simulates a vertical profile of radar reflectivity |
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| 21 | ! Originally Part of QuickBeam v1.04 by John Haynes & Roger Marchand. |
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| 22 | ! but has been substantially modified since that time by |
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| 23 | ! Laura Fowler and Roger Marchand (see modifications below). |
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| 24 | ! |
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| 25 | ! Inputs: |
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| 26 | ! |
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| 27 | ! [hp] structure that defines hydrometeor types and other radar properties |
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| 28 | ! |
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| 29 | ! [nprof] number of hydrometeor profiles |
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| 30 | ! [ngate] number of vertical layers |
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| 31 | ! |
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| 32 | ! [undef] missing data value |
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| 33 | ! (The following 5 arrays must be in order from closest to the radar |
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| 34 | ! to farthest...) |
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| 35 | ! |
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| 36 | ! [hgt_matrix] height of hydrometeors (km) |
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| 37 | ! [p_matrix] pressure profile (hPa) |
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| 38 | ! [t_matrix] temperature profile (K) |
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| 39 | ! [rh_matrix] relative humidity profile (%) -- only needed if gaseous aborption calculated. |
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| 40 | ! |
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| 41 | ! [hm_matrix] table of hydrometeor mixing rations (g/kg) |
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| 42 | ! [re_matrix] table of hydrometeor effective radii. 0 ==> use defaults. (units=microns) |
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| 43 | ! [Np_matrix] table of hydrometeor number concentration. 0 ==> use defaults. (units = 1/kg) |
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| 44 | ! |
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| 45 | ! Outputs: |
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| 46 | ! |
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| 47 | ! [Ze_non] radar reflectivity without attenuation (dBZ) |
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| 48 | ! [Ze_ray] Rayleigh reflectivity (dBZ) |
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| 49 | ! [h_atten_to_vol] attenuation by hydromets, radar to vol (dB) |
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| 50 | ! [g_atten_to_vol] gaseous atteunation, radar to vol (dB) |
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| 51 | ! [dBZe] effective radar reflectivity factor (dBZ) |
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| 52 | ! |
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| 53 | ! Optional: |
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| 54 | ! [g_to_vol_in] integrated atten due to gases, r>v (dB). |
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| 55 | ! If present then is used as gaseous absorption, independently of the |
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| 56 | ! value in use_gas_abs |
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| 57 | ! [g_to_vol_out] integrated atten due to gases, r>v (dB). |
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| 58 | ! If present then gaseous absorption for each profile is returned here. |
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| 59 | ! |
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| 60 | ! Created: |
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| 61 | ! 11/28/2005 John Haynes (haynes@atmos.colostate.edu) |
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| 62 | ! |
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| 63 | ! Modified: |
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| 64 | ! 09/2006 placed into subroutine form (Roger Marchand,JMH) |
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| 65 | ! 08/2007 added equivalent volume spheres, Z and N scalling most distrubtion types (Roger Marchand) |
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| 66 | ! 01/2008 'Do while' to determine if hydrometeor(s) present in volume |
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| 67 | ! changed for vectorization purposes (A. Bodas-Salcedo) |
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| 68 | ! |
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| 69 | ! 07/2010 V3.0 ... Modified to load or save scale factors to disk as a Look-Up Table (LUT) |
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| 70 | ! ... All hydrometeor and radar simulator properties now included in hp structure |
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| 71 | ! ... hp structure should be initialized by call to radar_simulator_init prior |
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| 72 | ! ... to calling this subroutine. |
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| 73 | ! Also ... Support of Morrison 2-moment style microphyscis (Np_matrix) added |
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| 74 | ! ... Changes implement by Roj Marchand following work by Laura Fowler |
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| 75 | ! |
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| 76 | ! 10/2011 Modified ngate loop to go in either direction depending on flag |
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| 77 | ! hp%radar_at_layer_one. This affects the direction in which attenuation is summed. |
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| 78 | ! |
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| 79 | ! Also removed called to AVINT for gas and hydrometeor attenuation and replaced with simple |
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| 80 | ! summation. (Roger Marchand) |
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| 81 | ! |
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| 82 | ! |
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| 83 | ! ----- INPUTS ----- |
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| 84 | |
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| 85 | logical, parameter :: DO_LUT_TEST = .false. |
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| 86 | logical, parameter :: DO_NP_TEST = .false. |
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| 87 | |
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| 88 | type(class_param), intent(inout) :: hp |
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| 89 | |
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| 90 | integer, intent(in) :: nprof,ngate |
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| 91 | |
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| 92 | real undef |
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| 93 | real*8, dimension(nprof,ngate), intent(in) :: & |
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| 94 | hgt_matrix, p_matrix,t_matrix,rh_matrix |
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| 95 | |
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| 96 | real*8, dimension(hp%nhclass,nprof,ngate), intent(in) :: hm_matrix |
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| 97 | real*8, dimension(hp%nhclass,nprof,ngate), intent(inout) :: re_matrix |
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| 98 | real*8, dimension(hp%nhclass,nprof,ngate), intent(in) :: Np_matrix |
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| 99 | |
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| 100 | ! ----- OUTPUTS ----- |
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| 101 | real*8, dimension(nprof,ngate), intent(out) :: Ze_non,Ze_ray, & |
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| 102 | g_to_vol,dBZe,a_to_vol |
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| 103 | |
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| 104 | ! ----- OPTIONAL ----- |
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| 105 | real*8, optional, dimension(nprof,ngate) :: & |
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| 106 | g_to_vol_in,g_to_vol_out ! integrated atten due to gases, r>v (dB). This allows to output and then input |
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| 107 | ! the same gaseous absorption in different calls. Optional to allow compatibility |
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| 108 | ! with original version. A. Bodas April 2008. |
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| 109 | ! real*8, dimension(nprof,ngate) :: kr_matrix |
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| 110 | |
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| 111 | ! ----- INTERNAL ----- |
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| 112 | |
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| 113 | real, parameter :: one_third = 1.0/3.0 |
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| 114 | real*8 :: t_kelvin |
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| 115 | integer :: & |
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| 116 | phase, & ! 0=liquid, 1=ice |
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| 117 | ns ! number of discrete drop sizes |
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| 118 | |
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| 119 | logical :: hydro ! true=hydrometeor in vol, false=none |
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| 120 | real*8 :: & |
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| 121 | rho_a, & ! air density (kg m^-3) |
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| 122 | gases ! function: 2-way gas atten (dB/km) |
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| 123 | |
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| 124 | real*8, dimension(:), allocatable :: & |
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| 125 | Di, Deq, & ! discrete drop sizes (um) |
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| 126 | Ni, & ! discrete concentrations (cm^-3 um^-1) |
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| 127 | rhoi ! discrete densities (kg m^-3) |
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| 128 | |
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| 129 | real*8, dimension(nprof, ngate) :: & |
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| 130 | z_vol, & ! effective reflectivity factor (mm^6/m^3) |
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| 131 | z_ray, & ! reflectivity factor, Rayleigh only (mm^6/m^3) |
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| 132 | kr_vol, & ! attenuation coefficient hydro (dB/km) |
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| 133 | g_vol ! attenuation coefficient gases (dB/km) |
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| 134 | |
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| 135 | |
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| 136 | integer,parameter :: KR8 = selected_real_kind(15,300) |
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| 137 | real*8, parameter :: xx = -1.0_KR8 |
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| 138 | real*8, dimension(:), allocatable :: xxa |
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| 139 | real*8 :: kr, ze, zr, pi, scale_factor, tc, Re, ld, tmp1, ze2, kr2, apm, bpm |
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| 140 | real*8 :: half_a_atten_current,half_a_atten_above |
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| 141 | real*8 :: half_g_atten_current,half_g_atten_above |
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| 142 | integer*4 :: tp, i, j, k, pr, itt, iff |
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| 143 | |
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| 144 | real*8 step,base, Np |
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| 145 | integer*4 iRe_type,n,max_bin |
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| 146 | |
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| 147 | integer start_gate,end_gate,d_gate |
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| 148 | |
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| 149 | logical :: g_to_vol_in_present, g_to_vol_out_present |
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| 150 | |
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| 151 | ! Logicals to avoid calling present within the loops |
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| 152 | g_to_vol_in_present = present(g_to_vol_in) |
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| 153 | g_to_vol_out_present = present(g_to_vol_out) |
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| 154 | |
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| 155 | ! |
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| 156 | ! load scaling matricies from disk -- but only the first time this subroutine is called |
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| 157 | ! |
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| 158 | if(hp%load_scale_LUTs) then |
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| 159 | call load_scale_LUTs(hp) |
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| 160 | hp%load_scale_LUTs=.false. |
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| 161 | hp%Z_scale_added_flag = .false. ! will be set true if scaling Look Up Tables are modified during run |
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| 162 | endif |
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| 163 | |
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| 164 | pi = acos(-1.0) |
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| 165 | |
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| 166 | ! ----- Initialisation ----- |
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| 167 | g_to_vol = 0.0 |
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| 168 | a_to_vol = 0.0 |
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| 169 | z_vol = 0.0 |
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| 170 | z_ray = 0.0 |
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| 171 | kr_vol = 0.0 |
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| 172 | |
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| 173 | ! // loop over each range gate (ngate) ... starting with layer closest to the radar ! |
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| 174 | if(hp%radar_at_layer_one) then |
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| 175 | start_gate=1 |
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| 176 | end_gate=ngate |
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| 177 | d_gate=1 |
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| 178 | else |
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| 179 | start_gate=ngate |
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| 180 | end_gate=1 |
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| 181 | d_gate=-1 |
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| 182 | endif |
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| 183 | do k=start_gate,end_gate,d_gate |
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| 184 | ! // loop over each profile (nprof) |
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| 185 | do pr=1,nprof |
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| 186 | t_kelvin = t_matrix(pr,k) |
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| 187 | ! :: determine if hydrometeor(s) present in volume |
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| 188 | hydro = .false. |
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| 189 | do j=1,hp%nhclass |
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| 190 | if ((hm_matrix(j,pr,k) > 1E-12) .and. (hp%dtype(j) > 0)) then |
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| 191 | hydro = .true. |
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| 192 | exit |
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| 193 | endif |
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| 194 | enddo |
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| 195 | |
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| 196 | ! :: if there is hydrometeor in the volume |
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| 197 | if (hydro) then |
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| 198 | |
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| 199 | rho_a = (p_matrix(pr,k)*100.)/(287.0*(t_kelvin)) |
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| 200 | ! :: loop over hydrometeor type |
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| 201 | do tp=1,hp%nhclass |
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| 202 | if (hm_matrix(tp,pr,k) <= 1E-12) cycle |
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| 203 | phase = hp%phase(tp) |
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| 204 | if (phase==0) then |
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| 205 | itt = infind(hp%mt_ttl,t_kelvin) |
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| 206 | else |
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| 207 | itt = infind(hp%mt_tti,t_kelvin) |
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| 208 | endif |
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| 209 | if (re_matrix(tp,pr,k).eq.0) then |
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| 210 | call calc_Re(hm_matrix(tp,pr,k),Np_matrix(tp,pr,k),rho_a, & |
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| 211 | hp%dtype(tp),hp%dmin(tp),hp%dmax(tp),hp%apm(tp),hp%bpm(tp), & |
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| 212 | hp%rho(tp),hp%p1(tp),hp%p2(tp),hp%p3(tp),Re) |
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| 213 | re_matrix(tp,pr,k)=Re |
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| 214 | else |
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| 215 | if (Np_matrix(tp,pr,k)>0) then |
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| 216 | print *, 'Warning: Re and Np set for the same ', & |
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| 217 | 'volume & hydrometeor type. Np is being ignored.' |
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| 218 | endif |
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| 219 | Re = re_matrix(tp,pr,k) |
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| 220 | endif |
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| 221 | |
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| 222 | iRe_type=1 |
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| 223 | if(Re.gt.0) then |
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| 224 | ! determine index in to scale LUT |
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| 225 | ! |
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| 226 | ! distance between Re points (defined by "base" and "step") for |
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| 227 | ! each interval of size Re_BIN_LENGTH |
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| 228 | ! Integer asignment, avoids calling floor intrinsic |
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| 229 | n=Re/Re_BIN_LENGTH |
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| 230 | if (n>=Re_MAX_BIN) n=Re_MAX_BIN-1 |
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| 231 | step=hp%step_list(n+1) |
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| 232 | base=hp%base_list(n+1) |
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| 233 | iRe_type=Re/step |
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| 234 | if (iRe_type.lt.1) iRe_type=1 |
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| 235 | |
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| 236 | Re=step*(iRe_type+0.5) ! set value of Re to closest value allowed in LUT. |
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| 237 | iRe_type=iRe_type+base-int(n*Re_BIN_LENGTH/step) |
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| 238 | |
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| 239 | ! make sure iRe_type is within bounds |
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| 240 | if (iRe_type.ge.nRe_types) then |
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| 241 | ! write(*,*) 'Warning: size of Re exceed value permitted ', & |
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| 242 | ! 'in Look-Up Table (LUT). Will calculate. ' |
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| 243 | ! no scaling allowed |
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| 244 | iRe_type=nRe_types |
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| 245 | hp%Z_scale_flag(tp,itt,iRe_type)=.false. |
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| 246 | else |
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| 247 | ! set value in re_matrix to closest values in LUT |
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| 248 | if (.not. DO_LUT_TEST) re_matrix(tp,pr,k)=Re |
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| 249 | endif |
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| 250 | endif |
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| 251 | ! use Ze_scaled, Zr_scaled, and kr_scaled ... if know them |
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| 252 | ! if not we will calculate Ze, Zr, and Kr from the distribution parameters |
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| 253 | if( (.not. hp%Z_scale_flag(tp,itt,iRe_type)) .or. DO_LUT_TEST) then |
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| 254 | ! :: create a distribution of hydrometeors within volume |
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| 255 | select case(hp%dtype(tp)) |
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| 256 | case(4) |
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| 257 | ns = 1 |
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| 258 | allocate(Di(ns),Ni(ns),rhoi(ns),xxa(ns),Deq(ns)) |
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| 259 | Di = hp%p1(tp) |
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| 260 | Ni = 0. |
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| 261 | case default |
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| 262 | ns = nd ! constant defined in radar_simulator_types.f90 |
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| 263 | allocate(Di(ns),Ni(ns),rhoi(ns),xxa(ns),Deq(ns)) |
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| 264 | Di = hp%D |
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| 265 | Ni = 0. |
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| 266 | end select |
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| 267 | call dsd(hm_matrix(tp,pr,k),re_matrix(tp,pr,k),Np_matrix(tp,pr,k), & |
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| 268 | Di,Ni,ns,hp%dtype(tp),rho_a,t_kelvin, & |
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| 269 | hp%dmin(tp),hp%dmax(tp),hp%apm(tp),hp%bpm(tp), & |
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| 270 | hp%rho(tp),hp%p1(tp),hp%p2(tp),hp%p3(tp)) |
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| 271 | |
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| 272 | ! calculate particle density |
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| 273 | if (phase == 1) then |
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| 274 | if (hp%rho(tp) < 0) then |
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| 275 | ! Use equivalent volume spheres. |
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| 276 | hp%rho_eff(tp,1:ns,iRe_type) = 917 ! solid ice == equivalent volume approach |
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| 277 | Deq = ( ( 6/pi*hp%apm(tp)/917 ) ** (1.0/3.0) ) * ( (Di*1E-6) ** (hp%bpm(tp)/3.0) ) * 1E6 |
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| 278 | ! alternative is to comment out above two lines and use the following block |
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| 279 | ! MG Mie approach - adjust density of sphere with D = D_characteristic to match particle density |
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| 280 | ! |
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| 281 | ! hp%rho_eff(tp,1:ns,iRe_type) = (6/pi)*hp%apm(tp)*(Di*1E-6)**(hp%bpm(tp)-3) !MG Mie approach |
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| 282 | |
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| 283 | ! as the particle size gets small it is possible that the mass to size relationship of |
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| 284 | ! (given by power law in hclass.data) can produce impossible results |
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| 285 | ! where the mass is larger than a solid sphere of ice. |
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| 286 | ! This loop ensures that no ice particle can have more mass/density larger than an ice sphere. |
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| 287 | ! do i=1,ns |
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| 288 | ! if(hp%rho_eff(tp,i,iRe_type) > 917 ) then |
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| 289 | ! hp%rho_eff(tp,i,iRe_type) = 917 |
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| 290 | ! endif |
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| 291 | ! enddo |
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| 292 | else |
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| 293 | ! Equivalent volume sphere (solid ice rho_ice=917 kg/m^3). |
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| 294 | hp%rho_eff(tp,1:ns,iRe_type) = 917 |
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| 295 | Deq=Di * ((hp%rho(tp)/917)**(1.0/3.0)) |
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| 296 | ! alternative ... coment out above two lines and use the following for MG-Mie |
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| 297 | ! hp%rho_eff(tp,1:ns,iRe_type) = hp%rho(tp) !MG Mie approach |
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| 298 | endif |
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| 299 | else |
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| 300 | ! I assume here that water phase droplets are spheres. |
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| 301 | ! hp%rho should be ~ 1000 or hp%apm=524 .and. hp%bpm=3 |
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| 302 | Deq = Di |
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| 303 | endif |
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| 304 | |
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| 305 | ! calculate effective reflectivity factor of volume |
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| 306 | xxa = -9.9 |
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| 307 | rhoi = hp%rho_eff(tp,1:ns,iRe_type) |
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| 308 | call zeff(hp%freq,Deq,Ni,ns,hp%k2,t_kelvin,phase,hp%do_ray, & |
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| 309 | ze,zr,kr,xxa,xxa,rhoi) |
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| 310 | |
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| 311 | ! test code ... compare Np value input to routine with sum of DSD |
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| 312 | ! NOTE: if .not. DO_LUT_TEST, then you are checking the LUT approximation |
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| 313 | ! not just the DSD representation given by Ni |
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| 314 | if(Np_matrix(tp,pr,k)>0 .and. DO_NP_TEST ) then |
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| 315 | Np = path_integral(Ni,Di,1,ns-1)/rho_a*1E6 |
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| 316 | ! Note: Representation is not great or small Re < 2 |
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| 317 | if( (Np_matrix(tp,pr,k)-Np)/Np_matrix(tp,pr,k)>0.1 ) then |
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| 318 | write(*,*) 'Error: Np input does not match sum(N)' |
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| 319 | write(*,*) tp,pr,k,Re,Ni(1),Ni(ns),10*log10(ze) |
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| 320 | write(*,*) Np_matrix(tp,pr,k),Np,(Np_matrix(tp,pr,k)-Np)/Np_matrix(tp,pr,k) |
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| 321 | write(*,*) |
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| 322 | endif |
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| 323 | endif |
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| 324 | |
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| 325 | deallocate(Di,Ni,rhoi,xxa,Deq) |
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| 326 | |
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| 327 | ! LUT test code |
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| 328 | ! This segment of code compares full calculation to scaling result |
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| 329 | if ( hp%Z_scale_flag(tp,itt,iRe_type) .and. DO_LUT_TEST ) then |
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| 330 | scale_factor=rho_a*hm_matrix(tp,pr,k) |
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| 331 | ! if more than 2 dBZe difference print error message/parameters. |
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| 332 | if ( abs(10*log10(ze) - 10*log10(hp%Ze_scaled(tp,itt,iRe_type) * & |
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| 333 | scale_factor)) > 2 ) then |
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| 334 | write(*,*) 'Roj Error: ',tp,itt,iRe_type,hp%Z_scale_flag(tp,itt,iRe_type),n,step,base |
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| 335 | write(*,*) 10*log10(ze),10*log10(hp%Ze_scaled(tp,itt,iRe_type) * scale_factor) |
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| 336 | write(*,*) hp%Ze_scaled(tp,itt,iRe_type),scale_factor |
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| 337 | write(*,*) re_matrix(tp,pr,k),Re |
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| 338 | write(*,*) |
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| 339 | endif |
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| 340 | endif |
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| 341 | |
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| 342 | else ! can use z scaling |
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| 343 | scale_factor=rho_a*hm_matrix(tp,pr,k) |
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| 344 | zr = hp%Zr_scaled(tp,itt,iRe_type) * scale_factor |
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| 345 | ze = hp%Ze_scaled(tp,itt,iRe_type) * scale_factor |
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| 346 | kr = hp%kr_scaled(tp,itt,iRe_type) * scale_factor |
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| 347 | endif ! end z_scaling |
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| 348 | |
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| 349 | kr_vol(pr,k) = kr_vol(pr,k) + kr |
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| 350 | z_vol(pr,k) = z_vol(pr,k) + ze |
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| 351 | z_ray(pr,k) = z_ray(pr,k) + zr |
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| 352 | |
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| 353 | ! construct Ze_scaled, Zr_scaled, and kr_scaled ... if we can |
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| 354 | if ( .not. hp%Z_scale_flag(tp,itt,iRe_type) ) then |
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| 355 | if (iRe_type>1) then |
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| 356 | scale_factor=rho_a*hm_matrix(tp,pr,k) |
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| 357 | hp%Ze_scaled(tp,itt,iRe_type) = ze/ scale_factor |
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| 358 | hp%Zr_scaled(tp,itt,iRe_type) = zr/ scale_factor |
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| 359 | hp%kr_scaled(tp,itt,iRe_type) = kr/ scale_factor |
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| 360 | hp%Z_scale_flag(tp,itt,iRe_type) = .true. |
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| 361 | hp%Z_scale_added_flag(tp,itt,iRe_type)=.true. |
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| 362 | endif |
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| 363 | endif |
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| 364 | |
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| 365 | enddo ! end loop of tp (hydrometeor type) |
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| 366 | |
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| 367 | else |
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| 368 | ! :: volume is hydrometeor-free |
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| 369 | kr_vol(pr,k) = 0 |
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| 370 | z_vol(pr,k) = undef |
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| 371 | z_ray(pr,k) = undef |
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| 372 | endif |
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| 373 | |
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| 374 | ! :: attenuation due to hydrometeors between radar and volume |
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| 375 | ! |
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| 376 | ! NOTE old scheme integrates attenuation only for the layers ABOVE |
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| 377 | ! the current layer ... i.e. 1 to k-1 rather than 1 to k ... |
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| 378 | ! which may be a problem. ROJ |
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| 379 | ! in the new scheme I assign half the attenuation to the current layer |
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| 380 | if(d_gate==1) then |
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| 381 | ! dheight calcuations assumes hgt_matrix points are the cell mid-points. |
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| 382 | if (k>2) then |
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| 383 | ! add to previous value to half of above layer + half of current layer |
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| 384 | a_to_vol(pr,k)= a_to_vol(pr,k-1) + & |
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| 385 | (kr_vol(pr,k-1)+kr_vol(pr,k))*(hgt_matrix(pr,k-1)-hgt_matrix(pr,k)) |
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| 386 | else |
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| 387 | a_to_vol(pr,k)= kr_vol(pr,k)*(hgt_matrix(pr,k)-hgt_matrix(pr,k+1)) |
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| 388 | endif |
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| 389 | else ! d_gate==-1 |
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| 390 | if(k<ngate) then |
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| 391 | ! add to previous value half of above layer + half of current layer |
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| 392 | a_to_vol(pr,k) = a_to_vol(pr,k+1) + & |
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| 393 | (kr_vol(pr,k+1)+kr_vol(pr,k))*(hgt_matrix(pr,k+1)-hgt_matrix(pr,k)) |
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| 394 | else |
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| 395 | a_to_vol(pr,k)= kr_vol(pr,k)*(hgt_matrix(pr,k)-hgt_matrix(pr,k-1)) |
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| 396 | endif |
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| 397 | endif |
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| 398 | |
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| 399 | ! :: attenuation due to gaseous absorption between radar and volume |
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| 400 | if (g_to_vol_in_present) then |
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| 401 | g_to_vol(pr,k) = g_to_vol_in(pr,k) |
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| 402 | else |
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| 403 | if ( (hp%use_gas_abs == 1) .or. ((hp%use_gas_abs == 2) .and. (pr == 1)) ) then |
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| 404 | g_vol(pr,k) = gases(p_matrix(pr,k),t_kelvin,rh_matrix(pr,k),hp%freq) |
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| 405 | if (d_gate==1) then |
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| 406 | if (k>1) then |
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| 407 | ! add to previous value to half of above layer + half of current layer |
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| 408 | g_to_vol(pr,k) = g_to_vol(pr,k-1) + & |
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| 409 | 0.5*(g_vol(pr,k-1)+g_vol(pr,k))*(hgt_matrix(pr,k-1)-hgt_matrix(pr,k)) |
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| 410 | else |
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| 411 | g_to_vol(pr,k)= 0.5*g_vol(pr,k)*(hgt_matrix(pr,k)-hgt_matrix(pr,k+1)) |
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| 412 | endif |
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| 413 | else ! d_gate==-1 |
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| 414 | if (k<ngate) then |
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| 415 | ! add to previous value to half of above layer + half of current layer |
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| 416 | g_to_vol(pr,k) = g_to_vol(pr,k+1) + & |
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| 417 | 0.5*(g_vol(pr,k+1)+g_vol(pr,k))*(hgt_matrix(pr,k+1)-hgt_matrix(pr,k)) |
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| 418 | else |
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| 419 | g_to_vol(pr,k)= 0.5*g_vol(pr,k)*(hgt_matrix(pr,k)-hgt_matrix(pr,k-1)) |
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| 420 | endif |
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| 421 | endif |
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| 422 | elseif(hp%use_gas_abs == 2) then |
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| 423 | ! using value calculated for the first column |
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| 424 | g_to_vol(pr,k) = g_to_vol(1,k) |
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| 425 | elseif (hp%use_gas_abs == 0) then |
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| 426 | g_to_vol(pr,k) = 0 |
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| 427 | endif |
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| 428 | endif |
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| 429 | |
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| 430 | ! Compute Rayleigh reflectivity, and full, attenuated reflectivity |
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| 431 | if ((hp%do_ray == 1) .and. (z_ray(pr,k) > 0)) then |
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| 432 | Ze_ray(pr,k) = 10*log10(z_ray(pr,k)) |
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| 433 | else |
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| 434 | Ze_ray(pr,k) = undef |
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| 435 | endif |
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| 436 | if (z_vol(pr,k) > 0) then |
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| 437 | Ze_non(pr,k) = 10*log10(z_vol(pr,k)) |
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| 438 | dBZe(pr,k) = Ze_non(pr,k)-a_to_vol(pr,k)-g_to_vol(pr,k) |
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| 439 | else |
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| 440 | dBZe(pr,k) = undef |
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| 441 | Ze_non(pr,k) = undef |
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| 442 | endif |
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| 443 | |
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| 444 | enddo ! end loop over pr (profile) |
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| 445 | |
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| 446 | enddo ! end loop of k (range gate) |
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| 447 | |
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| 448 | ! Output array with gaseous absorption |
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| 449 | if (g_to_vol_out_present) g_to_vol_out = g_to_vol |
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| 450 | |
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| 451 | ! save any updates made |
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| 452 | if (hp%update_scale_LUTs) call save_scale_LUTs(hp) |
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| 453 | |
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| 454 | end subroutine radar_simulator |
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