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Set up 1D long run

The objective of this long run is to apply the varying large scale forcings of the whole period from 16-12-2004 until 08-01-2005 instead of the average forcing for this period that is applied in the composite run. As initialisation we prescribe the same temperature and humidity profile as for the composite case. For the initial wind a profile based on the analysis of December 16 is prescribed.

Vertical Resolution and Duration

We require 2 different vertical resolutions
  • Standard "operational" resolution. This should the resolution that is commonly used in the operational 3d version of the participating 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 1013.9 mb can be found in Appendix_Long_Run . In the same appendix the initial profiles for this prescribed resolution can be found.

The duration of both runs should be 24 days.

Initial Profiles

We give the initial profiles in temperature and specific humidity which are the variables often used in SCM's. As initialisation we prescribe the same temperature and humidity profile as for the composite case. The initial profiles of liquid water, ice water and cloud cover can be put to zero. For the initial wind profiles we use idealised profiles based on the observations of December 16 2004.

  • u [m/s]
    0 < z < 570    -7.0 + (-8.85 + 7.0) / (570) * (z)
    570 < z < 6800     -8.85 + (4.0 + 8.85) / (6800 - 570) * (z - 570)
    6800 < z < 13400     4.0 + (26.2 - 4.0) / (13400 - 6800) * (z - 6800)
    13400 < z < 18600     26.2 + (0.5 - 26.2) / (18600 - 13400) * (z - 13400)
    18600 < z < 30000     0.5 + (-6.0 - 0.5) / (30000 - 18600) * (z - 18600)
    z > 30000     -6.0

  • v [m/s]
    0 < z < 9500    -1.5 + (-3.5 + 1.5) / (9500) * (z)
    9500 < z < 13500     -3.5 + (-13.5 + 3.5) / (13500 - 9500) * (z - 9500)
    13500 < z < 16000     -13.5 + (-5.0 + 13.5) / (16000 - 13500) * (z - 13500)
    16000 < z < 30000     -5.0 + (3.0 + 5.0) / (30000 - 16000) * (z - 16000)
    z > 30000     3.0

  • 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 = 1014.0 mb
  • sea surface temperature (SST) : A prescribed SST should be used that decreases linearly between T_s = 300.2 K at December 16 2004 and 299.6 at January 8 2005.

Large Scale Forcings

The large scale forcing terms are based on the analysis of the RACMO HindCast centered around the RICO Domain. From this hindcast 3 hourly profiles are constructed for the whole period from 16-12-2004 to 08-01-2005 which are availabe in netcdf. The forcings to be used are

  • horizontal and vertical advection profiles for u (m/s 1/s)
  • horizontal and vertical advection profiles for v (m/s 1/s)
  • horizontal and vertical advection profiles for T (K/s)
  • horizontal and vertical advection profiles for q_v (kg/kg 1/s)
  • Geowind profiles for u and v (m/s)
  • Surface pressure [Pa]

Finally a few remarks should be made
  • Radiation should be switched on for this case (contrary to composite case)
  • All other parameterisation schemes should be switched on.
  • Latitude: 18.0 N Degr.
  • Longitude: 61.5 W Degr. <

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