Index

Rundeck: P1SoM40

Created: Thu May 9 03:30:17 EDT 2024

tr_eqn

Module: SOCPBL

File: PBL.f

Summary: tr_eqn integrates differential eqns for the tracers, TR, using tridiagonal method over npbl(=8) sublayers between the surface (sublayer 1) and the middle of the first GCM layer (sublayer npbl). The boundary condition at the bottom is: kq * dtr/dz = sfac * trs - constflx, i.e. for moisture, sfac=cq*usurf, constflx=cq*usurf*qg, to get: kq * dq/dz = cq * usurf * (qs - qg); for new moisture (including downdraft effects), sfac=cq*(usurf-dusurf), constflx=cq*(usurf*qg + dusurf*qdns), or sfac=cq*usurf0, constflx=cq*(usurf*(qg+qdns)-usurf0*qdns), to get: kq * dq/dz = cq*(usurf*(qs-qg) + dusurf*(qdns-qs)). This should be flexible enough to deal with most situations. At the top, i.e., the middle of the first GCM layer, TR is prescribed.
Author : Ye Cheng/G. Hartke
Version:

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Declaration:

subroutine tr_eqn(tr0, tr, kq, dz, dzh, sfac, constflx, trtop, dtime, n)

Variables:

tr : real*8, dimension(n), intent(out)

z-profle of tracer concentration

tr0 : real*8, dimension(n), intent(in)

z-profle of tr at previous time step

kq : real*8, dimension(n-1), intent(in)

z-profile of moisture diffusivity

dz : real*8, dimension(n), intent(in)

(j) zhat(j)-zhat(j-1)

dzh : real*8, dimension(n-1), intent(in)

(j) z(j+1)-z(j)

sfac : real*8, intent(in)

factor multiplying surface tracer conc. in b.c.

constflx : real*8, intent(in)

the constant component of the surface tracer flux

trtop : real*8, intent(in)

tracer concentration at the first GCM layer

dtime : real*8, intent(in)

time step

n : integer, intent(in)

number of vertical subgrid main layers

sub : real*8, dimension(n)

dia : real*8, dimension(n)

sup : real*8, dimension(n)

rhs : real*8, dimension(n)

i : integer

loop variable

facttr : real*8