text: '''
  Python translation of CESM 1.2.1 code
  $CCSMROOT/models/atm/cam/src/control/physconst.F90
  for the pyCESM package
  Brian Rose
  June 2015
  
  Downloaded from
  https://github.com/brian-rose/pyCESM/blob/master/pyCESM/physconst.py
  
  On Oct 4 2017
  
  edited by RHWhite rachel.white@cantab.net
  
  '''
  from shr_const_mod import *
  
  avogad      = SHR_CONST_AVOGAD     #! Avogadro's number (molecules/kmole)
  boltz       = SHR_CONST_BOLTZ      #! Boltzman's constant (J/K/molecule)
  cday        = SHR_CONST_CDAY       #! sec in calendar day ~ sec
  cpair       = SHR_CONST_CPDAIR     #! specific heat of dry air (J/K/kg)
  cpliq       = SHR_CONST_CPFW       #! specific heat of fresh h2o (J/K/kg)
  cpocean     = SHR_CONST_CPSW       #! specific heat of ocean h2o (J/K/kg)
  karman      = SHR_CONST_KARMAN     #! Von Karman constant
  latice      = SHR_CONST_LATICE     #  ! Latent heat of fusion (J/kg)
  latvap      = SHR_CONST_LATVAP     #  ! Latent heat of vaporization (J/kg)
  pi          = SHR_CONST_PI         #! 3.14...
  pstd        = SHR_CONST_PSTD       #! Standard pressure (Pascals)
  r_universal = SHR_CONST_RGAS       #! Universal gas constant (J/K/kmol)
  rhoh2o      = SHR_CONST_RHOFW      #! Density of liquid water (STP)
  spval       = SHR_CONST_SPVAL      #!special value 
  stebol      = SHR_CONST_STEBOL     #! Stefan-Boltzmann's constant (W/m^2/K^4)
  h2otrip     = SHR_CONST_TKTRIP     #! Triple point temperature of water (K)
  c0          = 2.99792458E8         #! Speed of light in a vacuum (m/s)
  planck      = 6.6260755E-34        #! Planck's constant (J.s)
  #   ! Molecular weights
  mwco2       =  44.             #! molecular weight co2
  mwn2o       =  44.             #! molecular weight n2o
  mwch4       =  16.             #! molecular weight ch4
  mwf11       = 136.             #! molecular weight cfc11
  mwf12       = 120.             #! molecular weight cfc12
  mwo3        =  48.             #! molecular weight O3
  mwso2       =  64.
  mwso4       =  96.
  mwh2o2      =  34.
  mwdms       =  62.
  #   ! modifiable physical constants for aquaplanet
  gravit       = SHR_CONST_G     # ! gravitational acceleration (m/s**2)
  sday         = SHR_CONST_SDAY  # ! sec in siderial day ~ sec
  mwh2o        = SHR_CONST_MWWV  # ! molecular weight h2o
  cpwv         = SHR_CONST_CPWV  # ! specific heat of water vapor (J/K/kg)
  mwdry        = SHR_CONST_MWDAIR# ! molecular weight dry air
  rearth       = SHR_CONST_REARTH# ! radius of earth (m)
  tmelt        = SHR_CONST_TKFRZ # ! Freezing point of water (K)
  # !---------------  Variables below here are derived from those above
  # -----------------------
  rga          = 1./SHR_CONST_G                 #! reciprocal of gravit
  ra           = 1./SHR_CONST_REARTH            #! reciprocal of earth radius
  omega        = SHR_CONST_OMEGA                   #! earth rot ~ rad/sec
  rh2o         = SHR_CONST_RWV                     #! Water vapor gas constant ~J/K/kg
  rair         = SHR_CONST_RDAIR   #! Dry air gas constant     ~ J/K/kg
  epsilo       = SHR_CONST_MWWV/SHR_CONST_MWDAIR   #! ratio of h2o to dry air
  #   !molecular weights 
  zvir         = SHR_CONST_ZVIR                    #! (rh2o/rair) - 1
  cpvir        = SHR_CONST_CPVIR                   #! CPWV/CPDAIR - 1.0
  rhodair      = SHR_CONST_RHODAIR                 #! density of dry air at STP ~kg/m^3
  cappa        = (SHR_CONST_RGAS/SHR_CONST_MWDAIR)/SHR_CONST_CPDAIR  #! R/Cp
  #ez           ! Coriolis expansion coeff -> omega/sqrt(0.375)   
  Cpd_on_Cpv   = SHR_CONST_CPDAIR/SHR_CONST_CPWV
  
  #-------------------------------------
  # Other variables
  #------------------------------------
  K2C = 273.15
  