RFM Flags
HYD Flag



03AUG22
 Enabled
 Calculate CurtisGodson parameters
for planeparallel atmosphere
using height spacing (from
*HGT profile) to infer
g.M (gravity x molecular mass of air) in converting VMR to absorber amount
(basically allow unhydrostatic atmospheres — I'm aware that the
name of the flag is misleading!)
 Disabled
 Create CurtisGodson parameters for planeparallel atmosphere using
only pressure level information, with GRAVTY and WGTAIR from
phyadj_dat.f90 (ie assuming hydrostatic equilibrium).
 Restrictions
 Requires either
NAD or
ZEN flags to be enabled.
 Notes
 For planeparallel atmospheres
(NAD
or ZEN flags),
the CurtisGodson equivalent p,T and partial pressure for
each path can be expressed as explicit functions of the profile values
(see notes at the top of module vrtsum_sub.f90).
However to calculate
the absorber amount in each layer requires a factor g.M
where g=gravity, M=molar weight of air.
 The RFM default is to use internal values of
g=GRAVTY and M=WGTAIR
(see *PHY for how to
adjust these from their default values),
which makes
the plane parallel atmosphere calculations completely independent of
the altitude grid
 With the HYD flag the internal values
GRAVTY and WGTAIR are ignored and the product g.M
is inferred from the altitude grid spacing assuming hydrostatic equilibrium.
 Bugs
 None reported