Trying to get details

Hi just replace your geogrid data. Bhuvan's AWiFS data is in the same format as USGS. Before that make a copy of your old Geogrid data.

Prakash

hi Sudheer Bhakare

So, first you need to match/convert your Bhuvan's AWiFS LULC data classes into 24 classes of USGS classification. You can find the classes in the WRF user guide in the Chapter 3.

After the translation, you will have your data in the correct classification to insert in WRF. Now you need to convert the TIFF file (I am expecting you LULC data is a raster file) into binary format (BIL) required by WRF.

I usually use the convert_geotiff function from openWRF, which you ca find at https://github.com/openwfm/convert_geotiff

This tool will convert the tiff into binary and also will create the index file. This index file holds the information of your data, like resolution, description, extension, etc. (take a look in the other LULC in the geog folder).

After the conversion in binary format, move this files to a folder inside the geog data location (take care to not override the WRF default data)

The next step is to edit the GEOGRID.TBL file inside the WPS folder.

The GEOGRID.TBL holds the information of all land surface data to WPS/WRF, so you just need to edit the Land use section of the file, add one "name" to your data, set the interpolation method, and set the path to your data/folder.

This will helps WPS to find your data and how to proceed with it.

Next step is to edit your namelist.wps.

When you look at it, you will see the geog path is set to default.

for example, a wrf configuration of two domains, you will see something like this:

geog_data_res = 'default','default'

you just need to edit this line into

geog_data_res = 'name_you_set_in_TBL + default', ' name_you_set_in_TBL + default'

So, WPS will look first at the "name_you_set_in_TBL" data, and extract the LULC data to your domain. After extract your data, WPS will look at the default data to extract the other parameter to WRF

The chapter 3 of the user guide also helps you to set this variables, edit the GEOGRID.TBL, and namelis.wps.

Regards

Thanks for the interest on WRF compatible AWiFS derived LU/LC data, which are freely downloadable from NRSC website. This data contains 16 tiles of Indian region prepared using Indian satellite based AWiFS LU/LC (original resolution 56m) data of different years’ time frame covering Kharif, Rabi and Zaid crop seasons.

Please copy the downloaded 16 no of tiles from the attachment viz. [28801-30000.10801-12000, 28801-30000.12001-13200, …………....., 32401-33600.14401-15600] to original USGS "landuse_30s" (30 sec resolution) folder and overwrite with these 16 files(tiles), rest should be as it is. Before doing so, please keep a copy of original 767 numbers of USGS tiles for comparison.

You may go through the following reference

Gharai et.al., (2018); CURRENT SCIENCE, VOL. 115, NO. 12, 25 DECEMBER 2018, doi: 10.18520/cs/v115/i12/2301-2306

Rizzieri Pedruzzi

Dear Rizzieri,

Why Bhuvan's AWiFS LULC data classes should be converted into 24 classes of USGS classification please? In fact, I wonder if WRF does not recognize land use categories?

I am trying to use STRM as topography in WRF. Should I do the same step for STRM too?

Many thanks in advance,

Best regards,

Setareh Rahimi

Dear Setareh,

You need to convert the AWiFS LULC to USGS 24 classes (or Modis 20 or 21 classes) becase the WRF model only recognizes these LULC classes. If the AWiFS LULC classes are the same as USGS or MODIS from WRF, you just need to convert it into binary format and configure yout .TBL and namelist.wps, as I explained in the ealier post.

If the AWiFS LULC classes are not the same, you need to translate it into one of WRF's LULC classes.

Regarding the topography, you do not need to translate. You just need to make sure your topography tiff file is at lat lon projection, convert it into binary format, and configure the TBL and namelist.wps to WRF read it.

Anytime

Regards

Rizzieri

Rizzieri Pedruzzi

Dear Rizzieri,

Many thanks for your kind advice.

Kind regards,

Rizzieri Pedruzzi

Dear Rizzieri,

According to your advice I converted my land-use data( Esri-30m resolution) classes into MODIS classification. And then used "convert_geotiff function" to produce binary raster files. I also changed the following lines in GEOGRID.TBL.ARW :

landmask_water = 30m:17,21

interp_option = 30m:nearest_neighbor

rel_path = 30m:landuse30m

In WPS name list changed :

geog_data_res = ' 30m'

However after doing all these steps, and running geogrid.exe, I found out that land-use file produced by geogrid.exe has only one value (attached).

I wonder why did this happen?

May I ask you please advice me in this regard?

Best wishes,

Dear Setareh Rahimi

Can you check the geogrid.log file? This log tells you if the WPS found your data or not.

I noticed you used the name "30m" to point to your file. I would change to another name, since the "30m" is already used in WPS. I would use the "Esri-30m", for example.

• The GEOGRID.TBL would be like this:

landmask_water = Esri-30m:17,21

interp_option = Esri-30m:nearest_neighbor

rel_path = Esri-30m:landuse_Esri-30m/ OBS: remember to add a "/" in the end of the path

This is a sample of my GEOGRID.TBL

"name=LANDUSEF

priority=1

dest_type=categorical

z_dim_name=land_cat

dominant = LU_INDEX

landmask_water = LC_BR_SA_mapbiomas_250m_21:17,21

interp_option = LC_BR_SA_mapbiomas_250m_21:nearest_neighbor

rel_path = LC_BR_SA_mapbiomas_250m_21:landuse_BR_MapBiomas_SA_MODIS_21_250m/

• In the namelist.wps, I would set the resolution as:

geog_data_res = 'Esri-30m+default'

This way the WPS will first look for Esri-30m, and them it will move to default input data.

• About the "index" file generated by the "convert_geotiff function"

Take a look in the "index" file inside the folder of Esri-30m. Usually, the convert_geotiff assing the coordinates of known_y as the upper left cell, and the WPS gets the lower left as the first cell. Change your index, and set is as:

known_x = 1

known_y = 1

known_lat = lower left lat

known_lon = lower left lon

Here is an example of my "index" file

projection = regular_ll

known_x = 1

known_y = 1

known_lat = -60.9996586448

known_lon = -95.000000

dx = 2.245758e-03

dy = 2.245758e-03

type = categorical

signed = yes

units = "category"

description = "Brazil 21-category IGBP-MODIS landuse 250m"

mminlu="MODIFIED_IGBP_MODIS_NOAH"

wordsize = 2

tile_x = 1200

tile_y = 1200

tile_z = 1

category_min = 1

category_max = 21

tile_bdr = 3

missing_value = 17.000000

scale_factor = 1.000000

row_order = bottom_top

endian = little

iswater=17

islake=21

isice=15

isurban=13

I hope this helps.

Regards

Rizzieri

Rizzieri Pedruzzi

Dear Rizzieri,

Thanks for your advice.There are no issues with "geogrid.log file" and "GEOGRID.TBL". The issue is with the "convert_geotiff" !

I used below code to convert my tiff file to a raster binary:

./convert_geotiff -w 2 -c 8 -t 1200 -u "Category" -d "LAND-USE" land-use-geo.tiff

_______________________________________________________________________________

and the result is as follow:

projection = mercator

truelat1 = 0.000000

stdlon = 0.000000

known_x = 1

known_y = 33767

known_lat = 40.600704

known_lon = 46.638504

dx = 3.724413e-04

dy = 2.544101e-04

type = categorical

signed = yes

units = "Category"

description = "LAND-USE"

wordsize = 2

tile_x = 1200

tile_y = 1200

tile_z = 1

category_min = 1

category_max = 9

tile_bdr = 3

missing_value = 9.000000

scale_factor = 1.000000

row_order = bottom_top

endian = little

________________________________________________________________________________

as you can see there are some differences between my index file and the one you have.

like "projection", "iswater", "islake", "isice", "isurban".

My projection is "mercator" but yours is "regular_ll". How did you do this please?

Would you please kindly advice me where did I make a mistake please?

Another issue is that I have only 8 land-use category in my study area. So how can I provide missing values? because MODIS land use has 20 categories.

Best wishes

Dear Setareh Rahimi

Can you try to use this command to convert your data

./convert_geotiff -c 21 -t 1200 -u "Category" -d "LAND-USE" land-use-geo.tiff

This command will create a file with 21 categories. You should change to 20 if you did not use the lakes category in your raster file.

Maybe this is the issue you are facing

Regards

Rizzieri

Rizzieri Pedruzzi

Dear Rizzieri,

I previously tried the code you suggest, but the problem still exists. I should find a way to change the projection from mercator to regular_ll.

Best wishes,

Rizzieri Pedruzzi

Dear Rizzieri,

I could sort the issue out by changing my file coordinate system.

Kind regards,

Dear Setareh Rahimi

You need to have the tiff file in regular_ll to insert in convert_geotiff and WPS. It is the standard coordinate system for both.

I am glad you fixed the issue.

Anytime.

Regards

Rizzieri