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Output 1D models for composite run
General remarks on the data format
We ask for 4 NETCDF files, one with a time series of scalars, one the time series of hourly averaged profiles, one with the prescribed large scale forcings and one containing the initial profiles. Please provide in each NETCDF file any useful information as a global attribute, for example the investigator name, email address and model resolution and type of run (composite/long).
If you really have insurmountable problems in generating netcdf files, you can also submit your results in ASCII acording the instructions that can be found here.
General Notes
  • Liquid water includes only condensed water. So no rain water!
  • Liquid water potential temperature includes only condensed water. So no rain water!
  • For the required time series at a specified height: pick the most nearby level for this purpose.
  • The time series of the scalars should be provided at every 300 secs. Ideally, this should also be the timestep of the SCM. If such a timestep gives numerical instability problems, a smaller time step may be used.
  • The time series of the profiles should be provided once every hour and should be averaged over 3600 seconds ( 1hour).
  • The required fluxes should be the sum of the contributions of the convection and the pbl scheme.
Instantaneous profiles of the initial state
File name = lastname_profiles_ini.nc (e.g. Siebesma_profiles_ini.nc)

Dimensions:
  • {zf} Number of layers (full level)

Dependent variables, indexed (zf):
  • {zf} Altitude of layer mid-points (full level) [m]
  • {u} Zonal wind [m/s]
  • {v} Meridional wind [m/s]
  • {thetal} Liquid water potential temperature [K]
  • {qt} Total water (vapor+liquid+ice) [g/kg]
  • {rho} density [kg/m^3]
Time serie of scalars
Instantaneous values should be provided each 300 seconds .
File name = lastname_scalars.nc (e.g. Siebesma_scalars.nc)

Dimensions:
  • {time} Number of output times

Variables:
  • {time} - Time [s]
  • {zcb} - Cloud base height [m]
    (use here the height where the convection scheme detects cloud base. If there is no explicit convection scheme active use here the lowest model level height with a non-zero cloud fraction)
  • {ztop} - Cloud top height [m]
    (use here the highest level at which the convection scheme is active. If there is no explicit convection scheme active use here the highest model level height with a non-zero cloud fraction)
  • {zmaxcfrac} - Height of the model level with largest cloud fraction [m]
  • {M_base} - Mass flux at cloud base [kg/(m^2 s]

  • {LWP} - Liquid water path [g/m^2]
  • {cc} - Total Cloud cover [0-1]

  • {shf} - surface sensible heat flux [W/m^2]
  • {lhf} - surface latent heat flux [W/m^2]
  • {smf} - surface momentum flux [m^2/s^2]
  • {tke} - vertically integrated ρ·TKE [kg/s^2]
  • {v_lowlevel} - absolute velocity at the lowest model level [m/s]
  • {qv_lowlevel} - specific humidity at the lowest model level [g/kg]
  • {th_lowlevel} - potential temperature at the lowest model level [K]

  • {prec_2000} - Precipitation flux at 2000 m [W/m^2]
  • {prec_1500} - Precipitation flux at 1500 m [W/m^2]
  • {prec_1000} - Precipitation flux at 1000 m [W/m^2]
  • {prec_500} - Precipitation flux at 500 m [W/m^2]
  • {prec_srf} - Precipitation flux at the surface [W/m^2]

  • {qv_2000} - specific humidity at 2000 m [g/kg]
  • {qv_1500} - specific humidity at 1500 m [g/kg]
  • {qv_1000} - specific humidity at 1000 m [g/kg]
  • {qv_500} - specific humidity at 500 m [g/kg]

  • {th_2000} - potential temperature at 2000 m [K]
  • {th_1500} - potential temperature at 1500 m [K]
  • {th_1000} - potential temperature at 1000 m [K]
  • {th_500} - potential temperature at 500 m [K]

  • {Kh_300} - Eddy diffusivity for heat at 300 m [m^2/s]
  • {Kh_500} - Eddy diffusivity for heat at 500 m [m^2/s]
  • {Kh_1250} - Eddy diffusivity for heat at 1250 m [m^2/s]
Time serie of mean profiles
Profiles are to be averaged over 3600 s intervals for the duration of each simulation. The average over the first hour (1-3600 s) is given at t = 3600 s etc.
File name = lastname_profiles_avg.nc (e.g. Siebesma_profiles_avg.nc)

Dimensions:
  • {time} Number of output times
  • {zf} Number of layers (full level)
  • {zh} Number of layers (half level)

Independent variables:
  • {time} Time [s]

Dependent variables, indexed (time and zf or zh):
  • {zf} Altitude of layer mid-points (full level) [m]
  • {zh} Altitude of layer bottom-points (half level) [m]
  • {u} Zonal wind [m/s]
  • {v} Meridional wind [m/s]
  • {thetal} Liquid water potential temperature [K]
  • {qt} Total water (vapor+liquid+ice) [g/kg]
  • {qs} saturation specific humidity [g/kg]
  • {ql} condensed water (liquid plus ice) [g/kg]
  • {qr} Rain water [g/kg]
  • {cf} cloud fraction [0-1]
  • {rho} density [kg/m^3]
  • {wthl} &thetal flux [W/m^2]
  • {wqt} qt flux, [W/m^2]
  • {uw} Zonal momentum flux [kg/(m s^2)]
  • {vw} Meridional momentum flux [kg/(m s^2)]
  • {Mf} Mass flux [kg/(m ^2;s)]
  • {prec} Precipitation flux (positive downward) [W/m^2]
  • {w_up} vertical velocity in the cloudy updraft [m/s]
  • {thl_up} potential liquid water temperature &thetal,u in cloudy updraft [K]
  • {qt_up} total water specific humidity in the cloudy updraft [g/kg]
  • {ql_up} liquid water in cloudy updraft [g/kg]
  • {thv_up} potential virtual temperature &thetav,u in cloudy updraft [K]
Time serie of large scale forcings
Profiles are to be averaged over 3600 s intervals for the duration of each simulation. The average over the first hour (1-3600 s) is given at t = 3600 s etc.
File name = lastname_profiles_forc.nc (e.g. Siebesma_profiles_forc.nc)

Dimensions:
  • {time} Number of output times
  • {zf} Number of layers (full level)

Independent variables:
  • {time} Time [s]

Dependent variables, indexed (time and zf or zh):
  • {zf} Altitude of layer mid-points (full level) [m]
  • {dTdt_ls} Tendency due to large scale forcing of temperature [K/s]
    This forcing includes heating due to the prescribed subsidence, radiation and advection.
  • {dqdt_ls} Tendency due to large scale forcing of specific humidity [g/kg/s]
    This forcing includes moistening due to the prescribed subsidence, and advection.
  • {dudt_ls} Tendency of the u-wind component due to the geostrophic departure term [m/s^2]
  • {dvdt_ls} Tendency of the v-wind component due to the geostrophic departure term [m/s^2] <
Please do also send in a short description of the SCM you use that adresses shortly the following points. In addition a reference of a publication that contains a model description would also be helpful.

 Turbulence scheme:
  •  1a.  What kind of turbulence scheme ?  (e.g., K profile, Louis type, TKE-l, ...)
  •    b.  Give formulation of eddy diffusivity K.  For E-l and Louis-type scheme: give formulation length scale,  and for K-profile: how is this  profile determined ? (e.g., based on Richardson, Brunt-Vaisala frequency (N^2), Parcel method, other
  •    c.  Which variables are used for mixing (give them all) ? (e.g., theta, water vapor, and liquid water, wind) ? Do they use the same K
  •    d.  Moist (based on moist conserved variables) or dry formulation stability parameters (Ri, N^2). For moist formulations: How is interpolation between dry and wet cases done   (e.g., linear in cloud fraction.
  •    e.  Is top-entrainment prescribed or implicit?
  •    f.  For TKE schemes: TKE surface boundary condition. How is transport of TKE done (diffusion constant TKE transport).
  •    g.  Other things you would like to mention.


 Cumulus convection:

  •  2a. Separate scheme (which?) for cumulus convection, or is mixing in Cu represented by turbulence scheme.
  •    b. How is the cumulus scheme triggered (when is convection switched on)?
  •    c. If turbulence scheme: is there any special treatment of K for cumulus clouds ?
  •    d. If mass flux scheme, give: 1) Closure at cloud base  (cloud base value of massflux, q_t, theta_l), 2) entrainment and detrainment formulation for updraft (e.q., fixed or variable entrainment coefficients) and 3),   formulation detrainment at cloud top (e.g., Prescribed thickness, prescribed number of levels, dependent on stability inversion, ....)
  •    e. other things you would like to mention?


 Cloud fraction and condensation/evaporation:

  •  3a.  Diagnostic or prognostic cloud fraction. If diagnostic: based on which variables? If prognostic: based on which processes?
  •    b.  Does the model have a prognostic equation for liquid (ice) water, and if so, how is condensation and evaporation computed.
  •    c.  Which parameters are passed to the radiation code.


 Numerical aspects:

  •  4a. What is the vertical (and horizontal) resolution of the  model ?  In which model (climate model, mesoscale weather prediction model, regional model) ? Which time step do you use ?
  •    b. At which vertical resolution do you aim in the near future (say, coming 5 years)

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