This is the README file that explains each entry of the wrfsi.nl file. A. PROJECT_ID Section This section is used to fill in metadata entries that document the run. The settings in this section will not affect the WRFSI run, but are provided for convenience to allow the user to document their run in the output metadata. 1. SIMULATION_NAME Set this to a string describing the experiment or run. 2. USER_DESC Set this to a string describing who is running the configuration. B. FILETIMESEPC Section This section provides the start and stop times that bound the period for which you want SI to produce data. NOTE: If you are using wrfprep.pl to run the hinterp/vinterp programs (YOU SHOULD BE...this is our recommended method!), the script will edit these values for you automatically. Times are in UTC. 1. START_YEAR: 4-digit UTC year for start time. 2. START_MONTH: 2-digit UTC month for start time. 3. START_DAY: 2-digit UTC day of month for start time. 4. START_MINUTE: 2-digit UTC minute of month for start time. 5. START_SECOND: 2-digit UTC second of month for start time. 6. END_YEAR-END_SECOND: Same as 1-5, but for ending time. 7. INTERVAL: Interval in seconds between output times C. HGRIDSPEC section This is the section used to define your horizontal WRF grid. 1. NUM_DOMAINS: Integer number of nests. Currently, this must be set to 1. Once nesting is supported, it will be useful. 2. XDIM/YDIM: Integer number of points in the MOAD (Mother of all Domains). Only one set or xdim,ydim is required in wrfsi.nl even if NUM_DOMAINS > 1 since xdim and ydim for nests are calculated internally in WRFSI (see number 5 below). NOTE: The WRFSI defines the map to be what we refer to as the "non-staggered" grid. This implementation of the Arakawa-C stagger assumes all 3 component grids (U, V, and mass) are staggered with respect to these points. The U grid is staggered 0.5 gridpoints up w.r.t. the defined non-staggered points, the V grid is staggered 0.5 gridpoints to the right of the non-staggered points, and the mass grid is staggered 0.5 grid points up and 0.5 grid points to the right. To illustrate, here is an example for a case where (XDIM,YDIM) = (4,4): + V + V + V + U T U T U T U + V + V + V + U T U T U T U + V + V + V + U T U T U T U + V + V + V + The (+) points are the points exactly defined by the parameters in this namelist. The (T) points are the points on which the mass variables will be provided to and output by the WRF forecast model. The (U) points are the points on which the U momentum variables will be provided to and output by the WRF model. The (V) points are the points on which the V momentum variables will be provided to and output by the WRF model. Thus, if your WRFSI configuration uses dimensions (XDIM, YDIM), the model will output the following: Mass variables with dimensions (XDIM-1,YDIM-1) U-momentum with dimensions (XDIM,YDIM-1) V-momentum with dimensions (XDIM-1,YDIM) 3. PARENT_ID: Integer that represents the number for the parent of the nest. Note that the MOAD has no parent, and thus the first entry of PARENT_ID is always set to 1. The second entry must always = 1. The number of entries must equal NUM_DOMAINS. 4. RATIO_TO_PARENT: Integer specifying the nest ratio of each nest to its parent in terms of grid spacing. Typical values are 2 and 3 but this variable can be larger. The number of entries must be equal to NUM_DOMAINS. 5. DOMAIN_ORIGIN_[LLI/LLJ/URI/URJ]: These four parameters define the SW (lower left [LL]) and NE (upper right [UR]) i/j grid point corners of each nest within its parent domain. For the MOAD, the SW = 1,1 and the NE = xdim,ydim. The xdim,ydim values for nests can be calculated (as is done internally in the SI) as follows: xdim = (uri-lli)*ratio_to_parent+1, and ydim = (urj-llj)*ratio_to_parent+1. 6. MAP_PROJ_NAME: Character string specifying type of map projection. Valid entries are: "polar" -> Polar stereographic "lambert" -> Lambert conformal (secant and tangent) "mercator" -> Mercator "rotlat" -> NMM rotated latitude-longitude grid 7. MOAD_KNOWN_LAT/MOAD_KNOWN_LON: Real latitude and longitude of one known point within the grid. For now, this must be specified as the center of the grid. Values are in degrees, with postive latitude for the northern hemisphere and negative latitude for western hemisphere. Latitude must be between -90 and 90, and longitude between -180 and 180. 8. MOAD_STAND_LATS: 2 real values for the "true" latitudes (where grid spacing is exact). Must be between -90 and 90, and the values selected depend on projection: Polar-stereographic: First value must be the latitude at which the grid spacing is true. Most users will set this equal to their center latitude. Second value must be +/-90. for NH/SH grids. Lambert Conformal: Both values should have the same sign as the center latitude. For a tangential lambert conformal, set both to the same value (often equal to the center latitude). For a secant Lambert Conformal, they may be set to different values. Mercator: The first value should be set to the latitude you wish your grid spacing to be true (often your center latitude). Second value is not used. 9. MOAD_STAND_LONS: For now, this is one entry specifying the longitude in degrees East (-180->180) that is parallel to the y-axis of your grid. This should be set equal to the center longitude in most cases. 10. MOAD_DELTA_X/MOAD_DELTA_Y: Floating point values specifying grid spacing in meters in the west-east and north-south directions, respectively. For now, these two values must be the same. Grid spacing of nests is calculated internally in the SI and GUI (and displayed in the GUI) as follows (see src/lib/get_wrfsi_config.f: function grid_spacing_wrf_m(nest)): grid_spacing_wrf_m = moad_delta_x i = nest: do while (i.ne.1) grid_spacing_wrf_m = grid_spacing_wrf_m/ratio_to_parent(i) i = parent_id(i) enddo 11. SILAVWT_PARM_WRF (Please see README_toptwvl_silavwt in src/grid): 12. TOPTWVL_PARM_WRF (Please see README_toptwvl_silavwt in src/grid): D. SFCFILES Section This section is used to specify the paths to the tiled global geographical data sets, which are obtained from ftp://aftp.fsl.noaa.gov/divisions/frd-laps/WRFSI/Geog_Data IT IS NECESSARY THAT EACH DATA SET BE IN ITS OWN SUBDIRECTORY! 1. TOPO_30S: Path to the USGS-derived 30-second topographical height data. 2. PCTLAND_10M: Path to a 10-minute land fraction data set. 3. LANDUSE_30S: Path to the tiled 24-category USGS 30-second land usage categorical data. 4. SOILTYPE_TOP_30S: Path to the FAO top-layer 16-category soil-type data. 5. SOILTYPE_BOT_30S: Same as (4) but for bottom layer. 6. GREENFRAC: Path to the greenness fraction data. 7. SOILTEMP_1DEG: Path to the annual mean deep-layer temperature data. 8. ALBEDO_NCEP: Path to the monthly climatological albedo data set (normalized to local zenith ). 9. SSTEMP: Not yest used...placeholder for climatological SST data. E. INTERP_CONTROL section This section controls the horizontal and vertical interpolation of the input gridded data sets. 1. NUM_ACTIVE_SUBNESTS: If NUM_DOMAINS > 1 in the hgridspec section, (that is, you are employing nested grids within the mother of all domains {MOAD}), this parameter tells how many of the subnests you would like hinterp/vinterp to create initial conditions for. If you are only processing the MOAD, then NUM_ACTIVE_SUBNESTS must be 0. NUM_ACTIVE_SUBNESTS sets the dimensions of the ACTIVE_SUBNESTS parameter, and must be between 0 and NUM_DOMAINS-1 (inclusive). 2. ACTIVE_SUBNESTS: If NUM_ACTIVE_SUBNESTS >=1, then this is a list of integer values with NUM_ACTIVE_SUBNESTS elements. Each integer value is the domain ID of a nest for which you wish to have initial conditions. Each value should be unique, and each value must be >=2 and <=NUM_DOMAINS. This parameter is not used when processing only the MOAD (NUM_ACTIVE_SUBNEST = 0). This parameter, combined with NUM_ACTIVE_SUBNESTS, allows one to have multiple "sibling" nests configured during the localization, but only process selected ones when actually running the initialization of WRF. 3. PTOP_PA: Specifies model top in Pascals. Default is 5000 Pa. 4. HINTERP_METHOD: Integer specifying method of interpolation for atmospheric variables. Codes: 0: Nearest neighbor (not recommended) 1: 4-pt bilinear (use if input data has similar resolution as output) 2: 16-point 5. LSM_HINTERP_METHOD: Integer specifying the method of interpolation used for the land-masked fields. Codes are same as above. Recommended default is 0 or 1. NOTE: FOR USERS WISHING TO USE THE BACKGROUND DATA'S LANDUSE AND SOIL TYPE CATEGORIES, THIS MUST BE SET TO 0 AND YOU MUST OBTAIN "VEGCAT" AND "SOILCAT" FROM YOUR INPUT DATA SET, WHERE VEGCAT IS A 2D ARRAY OF DOMINANT LANDUSE CATEGORY (USGS 24-CAT) AND SOILCAT IS THE 2D ARRAY OF FAO DOMINANT SOIL CATEGORY. 6. NUM_INIT_TIMES: Integer, currently set to 1. This controls the number of output times to use the prefix specified by "INIT_ROOT" and "LSM_ROOT". The idea is for future support of analysis "nudging". The code will use the data specified by the INIT_ROOT/LSM_ROOT for time periods 1:NUM_INIT_TIMES, then switch to "LBC_ROOT" for the remaining time periods. If set to 0, all data comes from LBC_ROOT and CONSTANTS_FULL_NAME. Most users will set this to 0. However, setting it to 1 allows the model to be initialize with a different source of data for the initial conditions and land surface than what is used for lateral boundary conditions. 7. INIT_ROOT: Prefix of data to use for 1:NUM_INIT_TIMES. The wrfprep.pl script will look in ANALPATH (see SI_PATHS section) for files with this prefix and a time string suffix valid for the desired time. This entry is only used if NUM_INIT_TIMES > 0. 9. LBC_ROOT: Prefix of data files to use for lateral boundary condition times. The wrfprep.pl script will link in all files in "LBCPATH" that have this prefix and a valid time suffix in the correct range. 10. LSM_ROOT: For each NUM_INIT_TIME (when NUM_INIT_TIMES >0), the wrfprep.pl script will link in a file with this prefix found in LSMPATH that matches in time. This is designed to support data for the NOAH LSM coming from a source other than the INIT_ROOT. 11. CONSTANTS_FULL_NAME: Specifies a list of file names to look for in "CONSTANTS_PATH". Data contained in any of these files acutally found will be used at every output time, and will take precendence over duplicate data found in LSM_ROOT/INIT_ROOT/LBC_ROOT files. 12. VERBOSE_LOG: Logical. Setting to true provides a lot of logging for troubleshooting purposes. 13. OUTPUT_COORD: Specifies which vertical coordinate to output the data on. Four-character string value: 'ETAP': Output data on eta levels specified in LEVELS for input into the mass version of WRF. 'NMMH': Output data on NMM levels specified in LEVELS for input into the NCEP NMM-core of WRF. 'ZETA': NOT SUPPORTED ANY LONGER! MAY NOT WORK PROPERLY! 14. LEVELS: List of levels to use in the WRF model in ascending (atmospherically) order. If OUTPUT_COORD is set to 'ZETA', these values range from 0. to model top in meters. If OUTPUT_COORD is "ETAP", these values range from 1.0 to 0.0. F. SI_PATHS Section Specifys path to deGRIBed (grib_prep output) data files. In most cases all of these will be the same path ($EXT_DATAROOT/extprd). 1. ANALPATH: Path to search for files with INIT_ROOT prefix when NUM_INIT_TIMES > 0. 2. LBCPATH: Path to search for files with LBC_ROOT prefix for all time periods > NUM_INIT_TIMES. 3. LSMPATH: Path to search for files with LSM_ROOT prefix for all time periods 0:NUM_INIT_TIMES. 4. CONSTANTS_PATH: Path to search for files with CONSTANTS_FULL_NAME for every time period.