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What kind of gfs parameters I need to download for WRF simulation?

J

junius.Wang

New member
I would like to know what type of data should I choose during the process of downloading GFS data if I need to study the changes in wind speed in a region. If I download all the data types, the space required is too large and the download speed is also relatively slow.
 
junius.Wang said:
I would like to know what type of data should I choose during the process of downloading GFS data if I need to study the changes in wind speed in a region. If I download all the data types, the space required is too large and the download speed is also relatively slow.
Click to expand...
1 degree gfs data is the best when your network is bad！
 
In fact, I am downloading NCEP GFS 0.25 Degree Global Forecast Grids Historical Archive type data, but there are many variables in it, so I want to know in this case, can I choose Variables according to different needs? Do you have experience?
 
junius.Wang said:
In fact, I am downloading NCEP GFS 0.25 Degree Global Forecast Grids Historical Archive type data, but there are many variables in it, so I want to know in this case, can I choose Variables according to different needs? Do you have experience?
Click to expand...
Yes. The WRF user guide in WPS section gives a list about Variables needed by WRF.
 
Focus on the Vtable examples that are provided for specifically the GFS grids you are attempting to use (the NCEP 0.25 deg GRIB products). If you want higher resolution inputs for some lower boundary fields like SST and snow that improve upon GFS resolution you have options for this in WPS as well.
 
junius.Wang said:
I would like to know what type of data should I choose during the process of downloading GFS data if I need to study the changes in wind speed in a region. If I download all the data types, the space required is too large and the download speed is also relatively slow.
Click to expand...
Code: 
GRIB1| Level| From |  To  | metgrid  | metgrid | metgrid                                 |GRIB2|GRIB2|GRIB2|GRIB2|
Param| Type |Level1|Level2| Name     | Units   | Description                             |Discp|Catgy|Param|Level|
-----+------+------+------+----------+---------+-----------------------------------------+-----------------------+
  11 | 100  |   *  |      | TT       | K       | Temperature                             |  0  |  0  |  0  | 100 |
  33 | 100  |   *  |      | UU       | m s-1   | U                                       |  0  |  2  |  2  | 100 |
  34 | 100  |   *  |      | VV       | m s-1   | V                                       |  0  |  2  |  3  | 100 |
  52 | 100  |   *  |      | RH       | %       | Relative Humidity                       |  0  |  1  |  1  | 100 |
   7 | 100  |   *  |      | HGT      | m       | Height                                  |  0  |  3  |  5  | 100 |
  11 | 105  |   2  |      | TT       | K       | Temperature       at 2 m                |  0  |  0  |  0  | 103 |
  52 | 105  |   2  |      | RH       | %       | Relative Humidity at 2 m                |  0  |  1  |  1  | 103 |
  33 | 105  |  10  |      | UU       | m s-1   | U                 at 10 m               |  0  |  2  |  2  | 103 |
  34 | 105  |  10  |      | VV       | m s-1   | V                 at 10 m               |  0  |  2  |  3  | 103 |
   1 |   1  |   0  |      | PSFC     | Pa      | Surface Pressure                        |  0  |  3  |  0  |   1 |
   2 | 102  |   0  |      | PMSL     | Pa      | Sea-level Pressure                      |  0  |  3  |  1  | 101 |
 144 | 112  |   0  |  10  | SM000010 | fraction| Soil Moist 0-10 cm below grn layer (Up) |  2  |  0  | 192 | 106 |
 144 | 112  |  10  |  40  | SM010040 | fraction| Soil Moist 10-40 cm below grn layer     |  2  |  0  | 192 | 106 |
 144 | 112  |  40  | 100  | SM040100 | fraction| Soil Moist 40-100 cm below grn layer    |  2  |  0  | 192 | 106 |
 144 | 112  | 100  | 200  | SM100200 | fraction| Soil Moist 100-200 cm below gr layer    |  2  |  0  | 192 | 106 |
 144 | 112  |  10  | 200  | SM010200 | fraction| Soil Moist 10-200 cm below gr layer     |  2  |  0  | 192 | 106 |
  11 | 112  |   0  |  10  | ST000010 | K       | T 0-10 cm below ground layer (Upper)    |  0  |  0  |  0  | 106 |
  11 | 112  |  10  |  40  | ST010040 | K       | T 10-40 cm below ground layer (Upper)   |  0  |  0  |  0  | 106 |
  11 | 112  |  40  | 100  | ST040100 | K       | T 40-100 cm below ground layer (Upper)  |  0  |  0  |  0  | 106 |
  11 | 112  | 100  | 200  | ST100200 | K       | T 100-200 cm below ground layer (Bottom)|  0  |  0  |  0  | 106 |
  11 | 112  |  10  | 200  | ST010200 | K       | T 10-200 cm below ground layer (Bottom) |  0  |  0  |  0  | 106 |
  91 |   1  |   0  |      | SEAICE   | proprtn | Ice flag                                | 10  |  2  |  0  |   1 |
  81 |   1  |   0  |      | LANDSEA  | proprtn | Land/Sea flag (1=land, 0 or 2=sea)      |  2  |  0  |  0  |   1 |
   7 |   1  |   0  |      | SOILHGT  | m       | Terrain field of source analysis        |  0  |  3  |  5  |   1 |
  11 |   1  |   0  |      | SKINTEMP | K       | Skin temperature (can use for SST also) |  0  |  0  |  0  |   1 |
  65 |   1  |   0  |      | SNOW     | kg m-2  | Water equivalent snow depth             |  0  |  1  | 13  |   1 |
     |   1  |   0  |      | SNOWH    | m       | Physical Snow Depth                     |  0  |  1  |     |   1 |
-----+------+------+------+----------+---------+-----------------------------------------+-----------------------+
#
#
#
#  Vtable for GFS pressure-level data from the ncep server.
#
#  ftp://ftpprd.ncep.noaa.gov/pub/data/nccf/com/gfs/prod/gfs.ccyymmddhh/    (note hh at end)
#
#                          approx.    grid    hours      domain  dx      notes
#                         file size   no.
#
#  gfs.t12z.pgrb2f00       56000 Kb     4  3-h to 192-h  global  0.5 deg  (26 p-levels plus sfc and trop, 1000 to 10 mb).
#  gfs.t12z.pgrbf00.grib2  18000 Kb     3  3-h to 384-h  global  1.0 deg  (26 p-levels plus sfc and trop, 1000 to 10 mb).
#
#
#
#  For SNOWH, NCEP starts with the AFWA snow depth analysis and converts it to a water-equivalent.
#  For some reason, NCEP uses a different ratio in the GFS/GDAS than in the NAM and that which is assumed in WRF.
#  Therefore, we need to adjust SNOW and compute SNOWH in ungrib.
#
 
rdumais63 said:
Focus on the Vtable examples that are provided for specifically the GFS grids you are attempting to use (the NCEP 0.25 deg GRIB products). If you want higher resolution inputs for some lower boundary fields like SST and snow that improve upon GFS resolution you have options for this in WPS as well.
Click to expand...
Thank you for your help. This is a great idea!
 
William.Hatheway said:
Code: 
GRIB1| Level| From |  To  | metgrid  | metgrid | metgrid                                 |GRIB2|GRIB2|GRIB2|GRIB2|
Param| Type |Level1|Level2| Name     | Units   | Description                             |Discp|Catgy|Param|Level|
-----+------+------+------+----------+---------+-----------------------------------------+-----------------------+
  11 | 100  |   *  |      | TT       | K       | Temperature                             |  0  |  0  |  0  | 100 |
  33 | 100  |   *  |      | UU       | m s-1   | U                                       |  0  |  2  |  2  | 100 |
  34 | 100  |   *  |      | VV       | m s-1   | V                                       |  0  |  2  |  3  | 100 |
  52 | 100  |   *  |      | RH       | %       | Relative Humidity                       |  0  |  1  |  1  | 100 |
   7 | 100  |   *  |      | HGT      | m       | Height                                  |  0  |  3  |  5  | 100 |
  11 | 105  |   2  |      | TT       | K       | Temperature       at 2 m                |  0  |  0  |  0  | 103 |
  52 | 105  |   2  |      | RH       | %       | Relative Humidity at 2 m                |  0  |  1  |  1  | 103 |
  33 | 105  |  10  |      | UU       | m s-1   | U                 at 10 m               |  0  |  2  |  2  | 103 |
  34 | 105  |  10  |      | VV       | m s-1   | V                 at 10 m               |  0  |  2  |  3  | 103 |
   1 |   1  |   0  |      | PSFC     | Pa      | Surface Pressure                        |  0  |  3  |  0  |   1 |
   2 | 102  |   0  |      | PMSL     | Pa      | Sea-level Pressure                      |  0  |  3  |  1  | 101 |
 144 | 112  |   0  |  10  | SM000010 | fraction| Soil Moist 0-10 cm below grn layer (Up) |  2  |  0  | 192 | 106 |
 144 | 112  |  10  |  40  | SM010040 | fraction| Soil Moist 10-40 cm below grn layer     |  2  |  0  | 192 | 106 |
 144 | 112  |  40  | 100  | SM040100 | fraction| Soil Moist 40-100 cm below grn layer    |  2  |  0  | 192 | 106 |
 144 | 112  | 100  | 200  | SM100200 | fraction| Soil Moist 100-200 cm below gr layer    |  2  |  0  | 192 | 106 |
 144 | 112  |  10  | 200  | SM010200 | fraction| Soil Moist 10-200 cm below gr layer     |  2  |  0  | 192 | 106 |
  11 | 112  |   0  |  10  | ST000010 | K       | T 0-10 cm below ground layer (Upper)    |  0  |  0  |  0  | 106 |
  11 | 112  |  10  |  40  | ST010040 | K       | T 10-40 cm below ground layer (Upper)   |  0  |  0  |  0  | 106 |
  11 | 112  |  40  | 100  | ST040100 | K       | T 40-100 cm below ground layer (Upper)  |  0  |  0  |  0  | 106 |
  11 | 112  | 100  | 200  | ST100200 | K       | T 100-200 cm below ground layer (Bottom)|  0  |  0  |  0  | 106 |
  11 | 112  |  10  | 200  | ST010200 | K       | T 10-200 cm below ground layer (Bottom) |  0  |  0  |  0  | 106 |
  91 |   1  |   0  |      | SEAICE   | proprtn | Ice flag                                | 10  |  2  |  0  |   1 |
  81 |   1  |   0  |      | LANDSEA  | proprtn | Land/Sea flag (1=land, 0 or 2=sea)      |  2  |  0  |  0  |   1 |
   7 |   1  |   0  |      | SOILHGT  | m       | Terrain field of source analysis        |  0  |  3  |  5  |   1 |
  11 |   1  |   0  |      | SKINTEMP | K       | Skin temperature (can use for SST also) |  0  |  0  |  0  |   1 |
  65 |   1  |   0  |      | SNOW     | kg m-2  | Water equivalent snow depth             |  0  |  1  | 13  |   1 |
     |   1  |   0  |      | SNOWH    | m       | Physical Snow Depth                     |  0  |  1  |     |   1 |
-----+------+------+------+----------+---------+-----------------------------------------+-----------------------+
#
#
#
#  Vtable for GFS pressure-level data from the ncep server.
#
#  ftp://ftpprd.ncep.noaa.gov/pub/data/nccf/com/gfs/prod/gfs.ccyymmddhh/    (note hh at end)
#
#                          approx.    grid    hours      domain  dx      notes
#                         file size   no.
#
#  gfs.t12z.pgrb2f00       56000 Kb     4  3-h to 192-h  global  0.5 deg  (26 p-levels plus sfc and trop, 1000 to 10 mb).
#  gfs.t12z.pgrbf00.grib2  18000 Kb     3  3-h to 384-h  global  1.0 deg  (26 p-levels plus sfc and trop, 1000 to 10 mb).
#
#
#
#  For SNOWH, NCEP starts with the AFWA snow depth analysis and converts it to a water-equivalent.
#  For some reason, NCEP uses a different ratio in the GFS/GDAS than in the NAM and that which is assumed in WRF.
#  Therefore, we need to adjust SNOW and compute SNOWH in ungrib.
#
Click to expand...

Thank you very much for your help, but I am not familiar with the code you provided. I would like to know where to view this content?
 
junius.Wang said:
Thank you very much for your help, but I am not familiar with the code you provided. I would like to know where to view this content?
Click to expand...
If you look in the WPS/ungrib/Variable_Tables directory, you will see several different Vtables - each corresponding to a specific input data type. There is one that is specific to GFS (Vtable.GFS) and that is the one they shared with you above.
 
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