Defines useful constants for Earth.
fms_mod
| Name | Type | Value | Units | Description |
|---|---|---|---|---|
| RADIUS | real | 6371.e3 | m | radius of the earth |
| OMEGA | real | 7.292e-5 | 1/s | rotation rate of the planet (earth) |
| GRAV | real | 9.80 | m/s^2 | acceleration due to gravity |
| RDGAS | real | 287.04 | J/kg/deg | gas constant for dry air |
| KAPPA | real | 2./7. | --- | RDGAS / CP_AIR |
| CP_AIR | real | RDGAS/KAPPA | J/kg/deg | specific heat capacity of dry air at constant pressure |
| CP_OCEAN | real | 3989.24495292815 | J/kg/deg | specific heat capacity taken from McDougall (2002) "Potential Enthalpy ..." |
| RHO0 | real | 1.035e3 | kg/m^3 | average density of sea water |
| RHO0R | real | 1.0/RHO0 | m^3/kg | reciprocal of average density of sea water |
| RHO_CP | real | RHO0*CP_OCEAN | J/m^3/deg | (kg/m^3)*(cal/kg/deg C)(joules/cal) = (joules/m^3/deg C) |
| RVGAS | real | 461.50 | J/kg/deg | gas constant for water vapor |
| DENS_H2O | real | 1000. | kg/m^3 | density of liquid water |
| HLV | real | 2.500e6 | J/kg | latent heat of evaporation |
| HLF | real | 3.34e5 | J/kg | latent heat of fusion |
| HLS | real | 2.834e6 | J/kg | latent heat of sublimation |
| TFREEZE | real | 273.16 | degK | temp where fresh water freezes |
| WTMAIR | real | 2.896440E+01 | AMU | molecular weight of air |
| WTMH2O | real | 1.801534E+01 | AMU | molecular weight of water |
| WTMO3 | real | 47.99820E+01 | AMU | molecular weight of ozone |
| DIFFAC | real | 1.660000E+00 | --- | diffusivity factor |
| SECONDS_PER_DAY | real | 8.640000E+04 | seconds | seconds in a day |
| AVOGNO | real | 6.023000E+23 | atoms/mole | Avogadro's number |
| PSTD | real | 1.013250E+06 | dynes/cm^2 | mean sea level pressure |
| PSTD_MKS | real | 101325.0 | Newtons/m^2 | mean sea level pressure |
| REARTH | real | 6.356766E+08 | cm | radius of the earth |
| RADCON | real | ((1.0E+02*GRAV)/(1.0E+04*CP_AIR))*SECONDS_PER_DAY | deg sec/(cm day) | factor used to convert flux divergence to heating rate in degrees per day |
| RADCON_MKS | real | (GRAV/CP_AIR)*SECONDS_PER_DAY | deg sec/(m day) | factor used to convert flux divergence to heating rate in degrees per day |
| O2MIXRAT | real | 2.0953E-01 | --- | mixing ratio of molecular oxygen in air |
| RHOAIR | real | 1.292269 | kg/m^3 | reference atmospheric density |
| ALOGMIN | real | -50.0 | --- | minimum value allowed as argument to log function |
| FREZDK | real | 273.16 | deg K | melting point of water |
| STEFAN | real | 5.6734e-8 | W/m^2/deg^4 | Stefan-Boltzmann constant |
| VONKARM | real | 0.40 | --- | Von Karman constant |
| PI | real | 4.0*ATAN(1.0) | --- | ratio of circle circumference to diameter |
| RADIAN | real | 180.0/PI | --- | degrees per radian |
| C2DBARS | real | 1.e-4 | dbars | converts rho*g*z (in mks) to dbars: 1dbar = 10^4 (kg/m^3)(m/s^2)m |
| KELVIN | real | 273.15 | --- | degrees Kelvin at zero Celsius |
| EPSLN | real | 1.0e-40 | --- | a small number to prevent divide by zero exceptions |
call constants_init
use constants_mod, only: TFREEZE, grav_new => GRAV
real, parameter :: grav_inv = 1.0 / grav_new
tempc(:,:,:) = tempk(:,:,:) - TFREEZE
geopotential(:,:) = height(:,:) * grav_new
1. Renaming of constants.
2. Additional constants.