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Set up 1D composite run
General

With the set up of the 1d composite case we try to stay as close as possible to the LES case set up. The initial profiles and large scale forcings are identical to the LES case set up. Since the radiative tendencies are prescribed the SCM should be run with the radiation scheme turned off. All other parameterization schemes should be active.

Vertical Resolution and Duration

We require 2 different vertical resolutions
  • Standard "operational" resolution. This is the resolution that is commonly used in the operational 3d version of the SCM
  • High resolution run. This is a vertical resolution that is state of the art for high resolution limited area NWP and will become state of the art for GCM's in the foreseeable future. The A and B coefficients and the corresponding pressures given a surface pressure of 1015 mb can be found in Appendix . In the same appendix the initial profiles for this prescribed resolution can be found.
  • The duration of both runs should be 72 hours

Initial Profiles

We give the initial profiles in temperature and specific humidity which are the variables often used in SCM's. The temperature profile corresponds to the liquid water potential profile given for the set up of the 3d LES models. The initial profiles of liquid water, ice water and cloud cover can be put to zero.

  • u [m/s]
    0 < z < 4000    -9.9 + (-1.9 + 9.9) *z/4000
    4000 < z < 12000    -1.9 + (30.0 + 1.9) / (12000 - 4000) * (z - 4000)
    12000 < z < 13000     30.0
    13000 < z < 20000     30.0 - (30.0) / (20000 - 13000) * (z - 13000)
    z > 20000     0.0

  • v [m/s]
    z > 0     -3.8

  • q_v [g/kg]
    0 < z < 740   16.0 + (13.8 - 16.0) / (740) * z
    740 < z < 3260   13.8 + (2.4 - 13.8) / (3260 - 740) * (z - 740)
    3260 < z < 4000   2.4 + (1.8 - 2.4) / (4000 - 3260) * (z - 3260)
    4000 < z < 9000   1.8 + (0 - 1.8) / (10000 - 4000) * (z - 4000)
    z > 9000    0.0

  • Temperature [K]
    0 < z < 740    299.2 + (292.0 - 299.2) / (740) * z
    740 < z < 4000    292.0 + (278.0 - 292.0) / (4000 - 740) * (z - 740)
    4000 < z < 15000    278.0 + (203.0 - 278.0) / (15000 - 4000) * (z - 4000)
    15000 < z < 17500    203.0 + (194.0 - 203.0) / (17500 - 15000)* (z - 15000)
    17500 < z < 20000    194.0 + (206.0 - 194.0) / (20000 - 17500)* (z - 17500)
    20000 < z < 60000    206.0 + (270.0 - 206.0) / (60000 - 20000)* (z - 20000)

Surface Conditions

The only surface conditions that are prescribed are the SST and the mean surface pressure. The SCM's can run with their interactive surface scheme in otder to calculate the surface latent, sensible and momentum fluxes. The model should implicitly assume that the surface specific humidity is the saturation specific humidity at the SST .

  • surface pressure: ps = 1015.4 mb
  • sea surface temperature : T_s = 299.8 K

Large Scale Forcings and Radiation

The large scale advection and subsidence are based on the analysis of the RACMO HindCast centered around the RICO Domain. The radiation is based on an offline version of the ECMWF radiation scheme. More information on the forcings are described in background and are exactly equal to the prescribed large scale forcings applied to the 3D LES case up to 4000m. At this height and beyond the prescribed forcings are choosen such that they add up to zero when applied on the initial profile.


  • Large Scale Subsidence w [m/s] Apply the subsidence on the prognostic fields of q_v, q_l, T, u and v of the model.
    0 < z < 2260     - (0.005/2260) * z
    2260 < z < 4000     - 0.005
    4000 < z < 5000     - 0.005 + (0.005/ (5000 - 4000)) * (z - 4000)
    z > 5000     0.0
  • Large Scale Temperature Forcing due to advection and radiation, dT/dt [K/s]
    0 < z < 4000    - 2.51 / 86400 + (-2.18 + 2.51 )/ (86400*4000) * z
    4000 < z < 5000    - 2.18 / 86400 + ( 2.18 ) /(86400*(5000 - 4000)) * (z - 4000)
    z > 5000    0.0
  • Large Scale Horizontal Moisture Advection dqv/dt [(g/kg)/s]
    0 < z < 3000    -1.0 / 86400 + (0.345 + 1.0)/(86400*3000) * (z)
    3000 < z < 4000    0.345 / 86400
    4000 < z < 5000    0.345 / 86400 + (-0.345)/(86400 * (5000 - 4000)) * (z-4000)
    z > 5000    0.0
The Geostrophic Wind
The zonal u-component of the geostrophic wind is decreasing with 2.0 * 10^-3 s-1 corresponding with the observed wind. The geostrophic v-component is assumed to be equal to the meridional wind v.


  • Zonal component of the geostrophic wind ugeo (m/s)
    0 < z < 4000    -9.9 + (-1.9 + 9.9) *z/4000
    4000 < z < 12000    -1.9 + (30.0 + 1.9) / (12000 - 4000) * (z - 4000)
    12000 < z < 13000     30.0
    13000 < z < 20000     30.0 - (30.0) / (20000 - 13000) * (z - 13000)
    z > 20000     0.0
  • Meriodional component of the geostrophic wind vgeo (m/s)
       z > 0    -3.8
Other parameters
  • Latitude: 18.0 N Degr.
  • Longitude: 61.5 W Degr.
  • c_p: 1005. J kg^-1 K^-1
  • g: 9.81 m s^-2
  • Rd: 287. J kg^-1 K^-1
  • L: 2.5 * 10^6 J kg^-1
  • surface pressure: 1015.4 mb
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