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1093 Views 2 Replies Latest reply: May 7, 2012 12:53 AM by Gavin Roy RSS
Currently Being Moderated

Mar 12, 2012 5:05 PM

Land Cover Parameters

I am running CLM in LIS and am hoping to add a new land cover classification for switchgrass (replacing some existing crop areas across the U.S. Great Plains). I am having trouble finding documentation on how UMD's vegetation parameters are defined (an unlabeled file, umdvegparam.txt, is supplied in some of the testcases). Is there documentation on this anywhere, and should LIS be able to support the addition of a 14th classification?

 

Also, running LIS 6.0, I keep receiving the "landmask reading routine for source 4 is not defined" error when trying to use IGBP landcover data. Is this because of the capabilities of the version I'm running, or is it a directory path I failed to define?

 

Thank you in advance!


landmask reading routine for source 4 is not defined
  • Currently Being Moderated
    May 4, 2012 11:51 AM (in response to Gavin Roy)
    Re: Land Cover Parameters

    Hello Gavin,

     

    The public release of LIS 6.0 does not have support for reading the
    IGBP landcover data, which is why you are getting the "landmask
    reading routine for source 4 is not defined" error.

     


    As for the umdvegparam.txt that CLM2 reads, I also cannot find any
    good documentation.  But the file is read by lsms/clm2/clm_lsmMod.F90.
    Search that file for

     

    "open(111, file=clm_struc(n)%clm_vfile".

     

    Right below that is how the file is read and into which CLM2 variables
    the values go.  The file lsms/clm2/clmtype.F90 contains in-line documentation
    that describes these variables.

     

    Adding a new landcover classification is possible, but it will take
    some work.

     

    1) First you must create a new landcover file and make
    sure that it is consistent with the landmask file.  It seems that
    you are adding an additional class to the UMD landcover scheme, so I would
    take the existing UMD landcover file (in the CLM2 testcase, it is the
    file named ./input/UMD-25KM/UMD_veg0.25.1gd4r) and modify the desired
    grid-cells.

     

    2) You must create a new vegetation parameter file.  Here you must add
    an extra entry to the umdvegparam.txt for CLM2.

     

    3) For CLM2, you must create a new canopy height table (in the CLM2
    testcase, it is the file named ./input/clm_parms/clm2_ptcanhts.txt),
    providing canopy heights for your new vegetation class.  See the file
    lsms/clm2/canhtset.F90.

     

    4) You must edit the lis.config to use these settings:
    Landcover data source:           1
    Number of veg types:             14
    landcover file:                  your_new_file
    CLM vegetation parameter table:  your_new_file
    CLM canopy height table:         your_new_file

     

    Note that the UMD landcover file at 1 km resolution is a simple 2d gridded
    file, where the values are the landcover class for the grid-cell.  This
    is the "!landcover data is not tiled" case.  At all other resolutions, the
    UMD landcover file is a 3d gridded file.  The third dimension represents
    the fractions of all the landcover classification types for each grid-cell.
    This is the "!tiled" case.  Please read the params/landcover/read_UMDlc.F90 file.
    It will do a better job of demonstrating how to process the UMD landcover file.

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