Mesoscale Parallel Experiment Change Log

Experiment Name:  North American WRF-NMM with fully cycled land states and 2mb model top pressure

When Who What
2006/05/25/18 Parrish, Wu
  • Begin assimilation of NEXRAD Level 2 radial wind data in the GSI analysis
  • 2006/05/22/18 Derber, Parrish, Wu
  • Changes to GSI analysis:
    1. Turn off assimilation of surface temperature data over land in the GSI analysis
    2. Turn off MSU satellite data
    3. Tighten the gross error checks for all conventional data except winds.
    4. Increase iteration number from 50 -> 75
    5. +/- 15 minute window for all surface obs (was +/- 1.5 hours)
    6. Begin assimilation of NEXRAD Level 2.5 radial wind data in the GSI analysis
    7. The amplitude part of the background error was retuned to improve treatment of winds (reduced penalty function)
  • Cycled NDASX was restarted from the NDASY cycle
  • 2006/05/18/18 Ferrier, Janjic, Pyle, Black
  • Use vegetation component of z0base instead of z0 the calculation of the Zilitinkevitch fix for z0T in module_sf_myjsfc.F.
  • Include vertical variation of atmospheric density in computation of turbulent mixing of temperature, moisture, wind, and total condensate.
  • 2006/04/20/18 Lin, Rogers, Wu
  • Implement set of changes from NAMY parallel:
    1. Changed the computation of the difference between the 24h sum (12Z-12Z) of edas precip input and the daily gauge analysis in the pcpbudget code to inflate the daily gauge analysis data by 10% to account for under-catch of precip before the difference is computed. Previous version of the code for the WRF-NMM NDASX had no inflation of the analysed daily gauge data, while the ops NDAS has a 10% inflation.
    2. Revert back to pre-3/17 vertical background errors for humidity in the GSI analysis.
    3. Begin use of GPS-IPW data in GSI analysis
  • Cycled NDASX on white restarted from NDASY cycle on blue
  • 2006/04/04/18 Black, Chuang, Ferrier, Rogers
  • Switch to latest (27 March 2006) WRF Repository code
  • Numerous changes to restart file (add arrays for WRFNMM-to-SREFETA interpolation code, removed unused arrays). Because of this, NCO parallel NDASX on white restarted from NDASY cycle on blue.
  • 2006/03/24/00 Ferrier
  • The cloud layer emissivity (E) associated with a cloud optical depth (D) is currently parameterized as

    E = 1-.exp(-0.75*D),

    as defined over a contiguous cloud layer was changed to


    The 1.66 factor agrees with the equation in the WRF RRTM, while the extra factor of 1.5 accounts for the larger absorption coefficients used in NCAR's RRTM to convert from cloud mixing to optical cloud depth.

  • 2006/03/20/18 Pyle, Wu
  • Changes to the GSI analysis:
    1. Begin use of latest (March 2006) GSI release
    2. Use NMM-based background errors computed using an ensemble/Monte Carlo approach
  • When the model was cold-started (RESTRT=FALSE) the vegetation derived component of z0 is inadverently added to the full z0 variable twice. To fix this problem, the addition of the vegetative z0 has been removed from ./phys/module_sf_myfsfc.F, and the cycled NDAS has been restarted from an NDASY cycled restart file (where this problem was fixed on 3/17).
  • 2006/03/17/18 Black
  • Bug fixed in ./phys/module_ra_gfdleta.F : the modification of the top model layer pressure to account for the total ozone from the model top (2 mb) to the top of the atmosphere (0 mb) was incorrect because an undefined array index was used in the equation.
  • 2006/03/16/18 Pyle
  • Modified lateral boundary codes MKBND and COMBC to use GFS cloud water at the NAM lateral boundaries and to modify the LB winds so that the net flux around the boundaries is zero.
  • 2006/03/13/18 Black, Rogers
  • Bug fix in ./phys/module_cu_bmj.F : the vertical summation of the enthalpy that will then be conserved during the adjustment process within the cloud will now include a nonzero contribution from L(dq) that was missing before in the lowest cloud layer.
  • Switched to use the latest (2 March 2006) version of the WRF repository code
  • 2006/03/09/06 Gayno
  • Changed the surface update script to use the global 1/12th degree RTG_SST analysis instead of the 1/2 degree RTG_SST analysis.
  • 2006/03/06/18 Gayno, Pyle, Rogers
  • Restarted cycled NDASX from NDASY on blue to fix this problem:
    1. Changed the partial cycling code in NAMY (on 00z 3/4) so that it wrote out the z0 computed by SI/Real in the GDAS-based wrfinput file, instead of using z0 from the best available cycled NDAS WRF-NMM restart file. Since the NMM logical variable RESTRT=FALSE if partial cycling is invoked, the model was adding 1/2 of the vegetation z0 component to z0 every time the NDAS cycle was coldstarted. This led to z0 values 3-4x too big over a large portion of the NAM domain.
    2. Since NCO does not have the partial cycling capability working yet, the only way to get this fix in the NAMX parallel on white is to restart the NCO parallel from a wrf restart file from NAMY with the correct roughness lengths.
  • 2006/03/02/00 Rogers, J. Zhu
  • NAMX switched to point to the real-time parallel WRF-NMM NAM running on white, details:
    1. Parallel NDAS on white was restarted from the EMC NDASX on blue at 18z 2/27
    2. NAMX run on white will be done 4x/day
  • 2006/02/15/12 Wu
  • Changes to GSI analysis:
    1. Turn on tropospheric AMSUA radiance channels
    2. Updated NMM-based background error covariances
  • 2006/02/14/12 Black, Rogers
  • Switched to using latest (7 February) version of the WRF repository code, with added changed to do a clean restart from a non-zero forecast hour
  • Cycled NDAS restarted from ops GFS atmospheric states and cycled NDASX land states
  • 2006/01/27/00 Janjic
  • In module_sf_myjsfc.F set w* = 0 when dthv > 0 (stable case) when computing the Beljarrs correction for u*
  • 2006/01/21/00 Wu
  • GSI analysis changed to use background error covariances calculated from NMM forecasts.
  • 2006/01/19/12 Rogers
  • Pulled out model changes to allow for clean restart from a non-zero forecast hour due to problems with the timestep counter
  • Cycled NDAS restarted from ops GFS atmospheric states and cycled NDASX land states
  • 2006/01/18/12 Ek, Mitchell, Black, Rogers
  • Two changes to snow physics in the land-surface module:
    1. doubled snow thermal conductivity
    2. placed an upper limit of 0.98 on the snow cover fraction
  • Changes to WRF-NMM model to allow for clean restart from a non-zero forecast hour
  • 2006/01/17/12 Gayno, Rogers
  • First successful cold start of the parallel NDASX using the "partial cycling" option (atmospheric states from GDAS, land states from best available cycled WRF-NMM restart file)
  • 2006/01/14/12 Rogers
  • Modified the surface update script for SST, snow, and sea-ice analysis to perfrom the update at the start of the 12z NDASX (00z valid time) as was originally intended
  • 2006/01/11/00 Ferrier, Jovic
  • Change to BMJ code : At very cold temperatures (THETA=210 K) and pressures (2 mb), saturation mixing ratios were set to zero rather than having infinite values.
  • 2006/01/10/00 Ferrier, Gayno, Rogers, Wu
  • Fixed an error in the script which reads in the SST, snow, and sea-ice analysis, and updates them in the cycled WRF-NMM restart file at the start of the 00z NDAS. This error prevented these fields from being updated with the latest analysis, so that the SST and sea-ice used in each cycle was that from last date that the cycled NDAS was coldstarted (00z 12/28 for both NAMX and NAMY), while snow would cycle on itself continuously.
  • Modified WRF-NMM code to output the correct skin temperature in the array NMM_TSK, which is used by the GSI. Previously, this field reflected the skin temperature at 00-h if RESTRT=.FALSE., which is only invoked when the NMM cycle needs to be cold started.
  • Fixed error in surface update script which caused processing of the daily snow analysis to abort, resulting in continuous cycling of snow cover since NAMX was last coldstarted from the ops NAM
  • Begin use of the latest (Dec 2005) release of the GSI analysis
  • 2005/12/28/00 Rogers
  • The z0 component based on the standard deviation of the topography was not being applied during the NDAS forecast part of the full 12-km domain NMM run since it was started on 12/25. This problem has been fixed as of this date and the cycled NDAS for both NAMX and NAMY will be restarted from ops NAM land states and ops GFS atmospheric states.
  • 2005/12/27/12 Black, Ek, Janjic, Mitchell, Pyle, Rogers
  • NAMX changed to run full ops NAM domain, cycle started from ops NAM land states and ops GFS atmospheric states on 12z 12/25), using current 12/06/2005 repository code (with all parallel changes)
  • Changed LAI (Leaf Area index) from 2.0 to 4.0
  • Changes to z0 : enable a weak topography-based component and introduce a component based on the standard deviation of the topography
  • Changes to SFCDIF:
    1. Reduction of ZT over elevated terrain is only active in stable surface layers.
    2. A baseline lower CZET-like value of 3.0 was imposed, regardless of surface elevation
    3. PBL height computation changed to make it consistent with MYJPBL code and post
  • 2005/12/21/00 Black
  • Two bug fixes:
    1. The array SH2O was inproperly dimensioned in its declaration in subroutine TURBL. SH2O is a 3-D state array but in TURBL it is dimensioned as only 2-D. It is passed from solve_nmm through TURBL and the surface driver into the land surface package. SH2O is properly dimensioned in both the surface driver and the LSM package.
    2. Variable DZ was incorrectly calculated in subroutine CUCNVC. Two 1-D local working arrays, namely T(K) and Q(K), were being used to generate DZ(I,K,J) but T and Q are never being updated for each different I,J. DZ is subsequently passed into the BMJ code where it is used to calculate the layer pressure thicknesses.
  • 2005/12/20/00 Pyle, Janjic, Rogers
  • Switch back to new hybrid profile with concurrent modifications to the the MKBND code (which makes WRF-NMM lateral boundary conditions from GFS sigma coefficient files)
  • Restarted cycle from ops GFS atmospheric states, ops NAM land states
  • 2005/12/13/00 Rogers
  • Revert back to old hybrid coordinate due, changes to SI for new vertical profile were inconsistent with the MKBND code (which makes WRF-NMM lateral boundary conditions from GFS sigma coefficient files)
  • Restarted cycle from ops GFS atmospheric states, ops NAM land states
  • 2005/12/9/00 Janjic, Pyle
  • Switched to new hybrid vertical coordinate profile
  • Restarted cycle from ops GFS atmospheric states (necessary for hybrid profile change), ops NAM land states
  • 2005/12/5/12 Janjic
  • Modified MYJPBL to eliminate PBL oscillations noticed by Frank Freedman
  • Added code in PROFQ2 so that when there is no q2 (i.e. when q2 is equal to epsq2) el also drops to its floor value because el is a measure of spatial extension of q2.
  • 2005/12/2/00 Janjic
  • This change, put into the NAM NMM parallels on 10/20, was changed back since the original formulation was correct:
    1. Fixed an error in subroutine SFCDIF in which the first guess z0T is used to compute z+z0T instead of the converged value of z0T obtained iteratively.
  • 2005/11/29/00 Wu
  • Increased weight given to wind observations in qoption=2 test (normalized RH moisture variable) to improve fit to observed winds.
  • 2005/11/24/00 Ferrier, Rogers
  • Install 3 changes from NAMY parallel:
    1. Longwave temperature tendencies from the lowest two model layers are averaged together in order to address concerns that the layers may be too thin for the longwave scheme to provide accurate heating and cooling rates.
    2. Because the GFDL longwave (LW) radiation calculates heating rates and net radiative fluxes (rather than separately calculating the upward and downward components), the downward (incoming) LW is calculated as the sum of the net and the upward LW at the surface. The upward LW at the surface was based on the ground (skin) temperature, but now this has been changed to be the average of the skin and lowest model layer temperatures. The objective is to slow the rate that downward LW decreases when stable PBL conditions form in clear skies overnight.
    3. Cloud optical depths were reduced by the square of the cloud fraction in order to increase solar transmission through clouds, but now they are reduced by a factor proportional to the cloud fraction (as is the case for the NAM).
  • Restart cycled NDAS from NAMY restart file
  • 2005/11/18/00 Wu, Treadon
  • Changes to the GSI analysis:
    1. Turn off multi-variate correlation between temperature and humidity above sigma level =0.15
    2. Install small bug fixes from official GSI directory
    3. Restart cycle from ops GFS atmospheric states and ops NAM land states
  • 2005/11/15/00 Ferrier, Rogers
  • Restore 3% reduction in solar constant as in done in the ops NAM.
  • 2005/11/15/00 Wu, Treadon
  • Changes to the GSI analysis:
    1. Turned off AMSUA channels 1-5 and 15 for NOAA 15, 16 and 18. These channels, which influence the temperature near the surface, were causing analysis increments to be in the opposite direction from the raob increments in Northern Canada (sfc emissivity issues over snow).
    2. Increased the thinning of satellite data (currently about one data point in each grid box). The large amount of satellite data led to the raobs being effectively thrown out in certain regions.
  • 2005/11/10/00 Wu, Treadon
  • In the GSI, code was added to turn off the moisture constraint (limq) when using qoption=2 (normalized RH) as the moisture analysis variable. Using this constraint caused a negative feedback on the temperature analysis. While limq only affects the moisture field, the forcing it generated negatively fed back through the moisture-temperature-pressure coupling when using normalized RH as the moisture variable.
  • Cycled NDAS restarted from ops NAM.
  • 2005/11/8/00 Pyle
  • In the 00z 11/2 change, the topography-based modification to the ZILFC term was applied regardless of the value of DTHV instead of only when DTHV > 0.5. SFCDIF was changed to apply this modification in stable conditions when DTHV > 0.5, as was originally intended.
  • 2005/11/2/00 Pyle, Ferrier, Janjic
  • In SFCDIF, use a topography-based modification to the ZILFC term which is applied only when DTHV > 0.5; replacing the factor of 6 increase described in the 10/25/00z entry in the NAMXF parallel change log.
  • 2005/10/27/12 Ferrier, Rogers
  • Modified ozone profile to concentrate all ozone above 2 mb (the model top pressure) into the top model layer instead of being distributed through the atmosphere when the model top was at 50 mb
  • Removed the artficial 3% reduction in the solar constant which was meant to account for the absorption by ozone above the old 50 mb model top
  • Restarted cycled NDAS from ops NDAS land states and GFS atmospheric states
  • 2005/10/27/00 Chuang, Ferrier, Ek, Gayno, Janjic, Lin, Rogers, Wong
  • Details on previous changes from the repository version of the WRF-NMM are listed in the NAMXF parallel change log.
  • NAMXF and NAMXF2 have the same physics, lateral boundaries, and GSI analysis module, differences are:
    1. Model top pressure (NAMXF = 50 mb, NAMXF2=2 mb)
    2. The GSI in NAMXF uses NMM-based background errors, while NAMXF2 uses GFS-based background errors for now.
  • Page Last Modified: 1 March 2006