| 1 | subroutine moldiffcoeff_red(nq,dij,gcmind,ncompdiff2) |
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| 2 | |
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| 3 | use diffusion_h |
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| 4 | use tracer_h, only: noms, mmol |
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| 5 | IMPLICIT NONE |
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| 6 | c======================================================================= |
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| 7 | c subject: |
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| 8 | c -------- |
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| 9 | c Computing molecular diffusion coefficients |
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| 10 | c following Nair 94 (pg 131) |
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| 11 | c author: MAC 2002 |
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| 12 | c ------ |
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| 13 | c |
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| 14 | c======================================================================= |
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| 15 | #include "dimensions.h" |
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| 16 | |
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| 17 | c----------------------------------------------------------------------- |
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| 18 | c Input/Output |
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| 19 | c ------------ |
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| 20 | c integer,parameter :: ncompmoldiff = 12 |
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| 21 | integer ncompdiff2 |
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| 22 | integer gcmind(ncompdiff2) |
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| 23 | real dij(ncompdiff2,ncompdiff2) |
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| 24 | |
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| 25 | c Local variables: |
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| 26 | c --------------- |
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| 27 | INTEGER nq, n, nn, i,iq |
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| 28 | cccccccccccccccccccccccccccccccccccccccccccccccccccccccc |
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| 29 | c tracer numbering in the molecular diffusion |
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| 30 | cccccccccccccccccccccccccccccccccccccccccccccccccccccccc |
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| 31 | |
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| 32 | ! real :: dijh2co,dijh2n2,dijh2co2,dijh2o2,dijho,dijref,dijch4n2 |
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| 33 | real :: dijref,dijch4n2,dijch4co !TB16 |
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| 34 | ! integer :: g_h2,g_h,g_o |
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| 35 | integer :: g_ch4,g_n2 ! TB16 |
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| 36 | ! integer :: i_h2,i_h,i_o |
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| 37 | ! integer,parameter :: i_ch4 = 1 |
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| 38 | |
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| 39 | real dnh |
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| 40 | logical,save :: firstcall=.true. |
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| 41 | logical,parameter :: outputcoeffs=.false. ! to output 'coeffs.dat' file, |
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| 42 | ! set outputcoeffs=.true. |
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| 43 | |
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| 44 | ! Initializations at first call (and some sanity checks) |
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| 45 | if (firstcall) then |
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| 46 | ! identify the indexes of the tracers we'll need |
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| 47 | ! g_n2=igcm_n2 |
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| 48 | ! if (g_n2.eq.0) then |
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| 49 | ! write(*,*) "moldiffcoeff: Error; no N2 tracer !!!" |
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| 50 | ! stop |
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| 51 | ! endif |
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| 52 | |
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| 53 | cccccccccccccccccccccccccccccccccccccccccccccccccccccccc |
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| 54 | c fill array to relate local indexes to gcm indexes |
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| 55 | cccccccccccccccccccccccccccccccccccccccccccccccccccccccc |
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| 56 | |
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| 57 | ! gcmind(i_n2) = g_n2 |
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| 58 | c |
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| 59 | cccccccccccccccccccccccccccccccccccccccccccccccccccccccc |
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| 60 | firstcall= .false. |
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| 61 | endif ! of if (firstcall) |
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| 62 | |
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| 63 | dijch4n2 = 0.000018524 |
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| 64 | dijch4co = 0.000018524 |
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| 65 | |
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| 66 | ! find h2, h and o index in gcm |
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| 67 | ! these species are used to define the diffusion coefficients |
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| 68 | |
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| 69 | do n=1,nq |
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| 70 | if (noms(n) .eq. 'ch4_gas') g_ch4=n |
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| 71 | if (noms(n) .eq. 'n2') g_n2=n |
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| 72 | enddo |
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| 73 | |
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| 74 | print*,'moldiffcoeff_red: COEFF CALC' |
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| 75 | |
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| 76 | |
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| 77 | do n=1,ncompdiff2 |
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| 78 | dijref=0. |
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| 79 | if (noms(gcmind(n)) .eq. 'n2') dijref=dijch4n2 |
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| 80 | if (noms(gcmind(n)) .eq. 'co_gas') dijref=dijch4co |
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| 81 | |
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| 82 | if (dijref .gt. 0.0) then |
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| 83 | do nn=n,ncompdiff2 |
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| 84 | dij(nn,n)=dijref |
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| 85 | & *sqrt(mmol(g_ch4)/mmol(gcmind(nn))) |
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| 86 | if(n.eq.nn) dij(nn,n)=1.0 |
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| 87 | if(mmol(gcmind(n)).eq.mmol(gcmind(nn))) dij(nn,n)=1.0 |
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| 88 | dij(n,nn)=dij(nn,n) |
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| 89 | enddo |
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| 90 | endif |
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| 91 | |
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| 92 | if (dijref .eq. 0.0) then |
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| 93 | dijref=dijch4n2 |
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| 94 | dnh=dijref*sqrt(mmol(g_n2)/mmol(gcmind(n))) |
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| 95 | do nn=n,ncompdiff2 |
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| 96 | dij(nn,n)=dnh*sqrt(mmol(g_ch4)/mmol(gcmind(nn))) |
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| 97 | if(n.eq.nn) dij(nn,n)=1.0 |
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| 98 | dij(n,nn)=dij(nn,n) |
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| 99 | enddo |
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| 100 | endif |
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| 101 | |
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| 102 | enddo |
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| 103 | print*, 'TB16: dij=',dij(1,:) |
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| 104 | print*, 'TB16: dij=',dij(2,:) |
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| 105 | print*, 'TB16: dij=',dij(3,:) |
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| 106 | |
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| 107 | |
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| 108 | return |
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| 109 | end |
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| 110 | |
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