LAI and LANDUSE fraction in SRW ouput

Hi there,

I plan to use the SRW app output to drive the CMAQ model offline. However, I am unable to find the leaf area index (LAI) and land use fraction (LANDUSEF) for different land use categories in the output files. We need these fields in order to run the CMAQ model. Could you please let me know if they are part of the output or input files of SRW? 




Hi, Rajesh,

You can turn on the outputs for leaf area index (LAI) and land use fraction (LANDUSEF) by modifying the file diag_table, here are the details on the table:

The variables are defined in the meta data and the variable name may not be called LAI or LANDUSEF, for example:


  standard_name = leaf_area_index

  long_name = leaf area index

  units = none

  dimensions = (horizontal_loop_extent)

  type = real

  kind = kind_phys


  standard_name = land_area_fraction

  long_name = fraction of horizontal grid area occupied by land

  units = frac

  dimensions = (horizontal_loop_extent)

  type = real

  kind = kind_phys





Hi Rajesh,

To compliment Linlin's message, if you set "rdlai=.true." in the physics section of the input.nml namelist, and add the following line to the diag_table file, you can get LAI in the output write-component phyf*.nc files, but only when running with RUC-LSM:

"gfs_sfc",     "xlaixy",      "xlaixy",    "fv3_history2d",  "all",  .false.,  "none",  2

For Noah or Noah MP, we have not yet been able to successfully output LAI.  We're testing a few things. 

If you're looking for land fraction, then you can refer to Linlin's message.  If you want land-use fraction, it's not currently available in FV3 and is therefore not used by any of the LSMs.  We will look into this to see if it can be added in the future.  If you want land use type/vegetation type, that's "vtype".