Mesoscale Parallel Experiment Change Log

Experiment Name:  Eta-32 with modified precipitation assimilation, modified PBL physics, modified land-surface physics, assimilation of NEXRAD level 2.5 radial wind data

When Who What
2005/01/15/12 Rogers, Ek, Ferrier, Mitchell
  • Revert to ETAY version of cloud/radiation changes
  • Change snow emissivity form 0.95 to 0.9
  • Restart cycled EDAS from ETAY control
  • 2004/12/27/12 Bender, Keyser
  • Turned back on use of Level 2.5 NEXRAD data in 3DVAR, only sites with good lat/lon data (about 15-20% of original total) are included in the data dump.
  • 2004/12/08/00 Bender, Keyser, Rogers
  • Revert back to ops radial wind data due to 75-85% of the Level 2.5 supob reports in /dcom/us007003/*/b006/xx002 having a missing superob longitude (SUPLON) and a superob latitude (SUPLAT) equal to 65.530 (for every report with a missing SUPLON). It appears that something is corrupt in the incoming Level 2.5 raw files from which SUPLAT and SUPLON are generated.
  • 2004/12/03/12 Ek, Mitchell, Ferrier, Rogers
  • Snow emissivity changed from 0.9 to 0.95
  • 2004/12/03/00 Ek, Mitchell
  • Added the effects of snow emissivity in the calculation of effective snow-ground sfc temperature. This was done by changing the value from 1.0 to 0.9.
  • 2004/11/20/00 Ferrier
  • For the optical depth parameterization for grid-scale processes in the absence of convection, changed CTau=0.08*min(1., Qc/Q0) to CTau=800*Qc.
  • 2004/10/28/12 Ek, Mitchell
  • Increase minimum stomatal conductance from 40s/m to 70s/m for cropland, pasture, and grassland vegetation types in order to decrease surface evaporation.
  • 2004/10/01/00 Ek, Mitchell
  • Leaf area index (LAI) parameter in LSM physics changed from 1.0 to 2.0
  • 2004/09/24/12 Pondeca, Rogers
  • Begin use of new 3DVAR analysis which uses a 2dvar surface analysis to assimilate surface temperature data.
  • 2004/09/20/12 Rogers
  • Began use of 3DVAR code assimilating NEXRAD level 2.5 radial wind data
  • 2004/09/17/12 Mitchell, Ek
  • Change "LAI_DATA" in LSM physics from 3.0 to 1.0
  • 2004/09/02/12 Ferrier, Mitchell
  • Revert to ops versions of MIXLEN, PRODQ2, switch to experimental versions of DIFCOF, TURBL, SFCDIF (see 8/23/04 entry)
  • 2004/08/31/00 Lin
  • New precipitation assimilation scheme (routine ADJPPT) modified to account for the fact that the variable F_rain is actually the fraction of liquid condensate that is rain, not the fraction of total condensate that is liquid rain
  • 2004/8/5/12 Ek, Wong, Mitchell. Rogers
  • Upgrade to version 2.8 of NoahLSM with new hi-res soil and vegetation type definitions:
    1. Urban and Built-Up Land
    2. Dryland Cropland and Pasture
    3. Irrigated Cropland and Pasture
    4. Mixed Dryland/Irrigated Cropland and Pasture
    5. Cropland/Grassland Mosaic
    6. Cropland/Woodland Mosaic
    7. Grassland
    8. Shrubland
    9. Mixed Shrubland/Grassland
    10. Savanna
    11. Deciduous Broadleaf Forest
    12. Deciduous Needleleaf Forest
    13. Evergreen Broadleaf Forest
    14. Evergreen Needleleaf Forest
    15. Mixed Forest
    16. Water Bodies
    17. Herbaceous Wetland
    18. Wooded Wetland
    19. Barren or Sparsely Vegetated
    20. Herbaceous Tundra
    21. Wooded Tundra
    22. Mixed Tundra
    23. Bare Ground Tundra
    24. Snow or Ice
    25. Playa
    26. Lava
    27. White Sand
    1. SAND
    4. SILT LOAM
    5. SILT
    6. LOAM
    9. CLAY LOAM
    10. SANDY CLAY
    11. SILTY CLAY
    12. CLAY
    14. WATER
    15. BEDROCK
    16. OTHER(land-ice)
    17. PLAYA
    18. LAVA
    19. WHITE SAND
  • Land states restarted from 00Z 7/28/2004 ETAL (last ETAL run w/hi-res soil and veg types)
  • 2004/7/27/12 Ek, Mitchell
  • Added version 2.7 of noah LSM land-surface physics, including changes to model formulation parameters, and some additional numerical refinements. Effects of the vegetation greenness factor are removed from the snow albedo formulation, leading to an increase in albedo under snow-covered conditions. The Eta model cloud microphysics now passes the fraction of frozen precipitation to the Noah LSM, eliminating the crude determination of frozen precipitation by the Noah LSM based on lowest (atmospheric) model level air temperature. Separate snow sublimation and non-snow-covered evaporation is now considered for patchy snow cover conditions when snowpack is shallow, reducing snow sublimation and snowpack depletion. Changes to parameters in the patchy snow cover formulation decrease the snow depth for 100 percent snow cover. A reduction in vegetation-dependent soil moisture threshold values will increase transpiration. The depth at which the lower boundary condition on soil temperature is applied is increased from 3 meters to 8 meters. The thermal heat capacity of mineral soil has been changed to a more standard value. A change to the coefficient in the thermal-roughness length calculation will decrease the surface skin-atmosphere temperature gradient. The sea-ice albedo is changed from 0.60 to 0.65. A diagnostic soil heat flux calculation included at the end of the Noah LSM code leads to better closure of the surface energy budget.
  • Reduced parameter CZIL from 0.2 to 0.1. This change will reduce aerodyamnic resistance (i.e. surface turbulent exchange coefficients are too low during mid-day)
  • Parameter SMHIGH_DATA reduced from 6.0 to 3.0; this will raise the value of the reference soil moisture value below which vegetation becomes stressed (SMCREF), which (at first order) should reduce the transpiration (surface moisture flux).
  • 2004/7/16/00 Ferrier, Freedman, Janjic, Ek, Mitchell, Rogers
  • DIFCOF.F & TURBL.F changed: In very stable conditions when the PBL depth is diagnosed as the lowest Eta model level above the surface, impose a lower limit on eddy diffusivity (Km,Kh) of 0.5 m^2/s up to (and one level above) the inversion height in order to maintain atmospheric turbulent mixing at least above this nominally small value.
  • Subroutine SFCDIF was changed : For the profile functions for the very stable boundary layer (z/L=>1), impose a consistent limit on z0/L.
  • Changes to subroutines MIXLEN and PRODQ2 which removes mixing length limits under stable conditions -- should increase (downward) turbulent heat mixing in stable conditions.
  • 2004/05/04/00 Lin
  • Fixed error which caused the analyzed precipitation to be incorrectly fed to the top soil layer.