Modification of land use and water temperatures

Compiling NMM/ARW code for EMS system, upgrading WRF cores on your own, changing EMS scripts to suit your particular needs, and other modifications to original EMS distribution goes in this forum. These are officially unsupported actions.
meteoadriatic
Posts: 1515
Joined: Wed Aug 19, 2009 10:05 am

Re: Modification of land use and water temperatures

Post by meteoadriatic » Sun Apr 10, 2011 10:04 am

dmbrown1 wrote:I had a problem last fall where the lakes should have been frozen, but weren't in the model and were adding way too much heat to the atmosphere. I never solved it - they just eventually froze a number of weeks later.
I think that model handle lakes same as it handles sea. So it will initialize with sea temperature and cool during night as slow as sea surface does. It is very possible though, that I'm wrong here. But, as I replaced these lakes with wetland type everything is now ok. Maybe you can try that also and see if it has sense.

joseph
Posts: 1
Joined: Tue Aug 30, 2011 1:19 pm

Re: Modification of land use and water temperatures

Post by joseph » Tue Aug 30, 2011 1:31 pm

dmbrown1 wrote:Regarding the Java program (colopolo):

It looks to me like Java is not finding the program. Read.class and all related files (including the ones you want to change) MUST be in the same directory, and you must be IN that directory, otherwise you may get this error. Hopefully this helps.
I put Read.class, Write.class, Colours.cont and landuse data file in the same directory on PC (Windows, Java 6) but got the same massage:
Exception in thread "main" java.lang.NoClassDefFoundError: com/trend/iwss/jscan/runtime/CallContext
at Read.main(Read.java:51)
Caused by: java.lang.ClassNotFoundException: com.trend.iwss.jscan.runtime.CallContext
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)

What can I do to run Read and Write ?

nisha
Posts: 2
Joined: Mon Nov 07, 2011 7:52 pm

Re: Modification of land use and water temperatures

Post by nisha » Mon Nov 07, 2011 8:10 pm

Hi dmbrown,

Excellent work! I am trying to modify some parameters (such as albedo, roughness) of urban and built-up land cover (MODIS) to see the impact on model output. I was wondering if i follow the simple instructions given by you in part B (where you make changes to VEGPARM.TBL and LANDUSE.TBL), it would be sufficient for the sensitivity experiments I wish to perform. Because, I do not want to insert a new land use type, but just modify the existing one to have different surface properties.
Also, is there a good reference/document that provides guidance for performing land-use modifications in WRF?

Regards,
Nisha

dmbrown1
Posts: 15
Joined: Tue Aug 10, 2010 9:02 pm

Re: Modification of land use and water temperatures

Post by dmbrown1 » Fri Nov 18, 2011 12:15 am

joseph,

I have never tried to run this on Windows, but there are some different conventions for how files are stored on Windows vs Linux. See if you can try it on Linux. On a side note, at some point I'll try to create the programs as a perl script so that everyone can see the source code and modify them however they choose.

dmbrown1
Posts: 15
Joined: Tue Aug 10, 2010 9:02 pm

Re: Modification of land use and water temperatures

Post by dmbrown1 » Fri Nov 18, 2011 12:21 am

Nisha,

I have not found a good reference for performing land use modifications, which is why I posted what I have learnt from experimentation.

When changing these parameters, you have to be careful, because the tables are different depending on which surface physics paramaterisation you are using (described at the beginning of the topic).

If you change things the way you say, I think it will be sufficient. Remember that if you change the roughness of urban areas, it will change the roughness of all urban areas, not just the one you want. I have successfully changed roughnesses of urban areas using this method and seen results in the model.

nisha
Posts: 2
Joined: Mon Nov 07, 2011 7:52 pm

Re: Modification of land use and water temperatures

Post by nisha » Thu Dec 22, 2011 9:53 pm

Thanks a lot for your input :)
will keep in mind.

Nisha

Maikel
Posts: 1
Joined: Tue Jun 04, 2013 6:00 pm

Re: Modification of land use and water temperatures

Post by Maikel » Tue Jun 04, 2013 6:14 pm

Hello! My intention is to remove the lakes of a specific area. So I made ​​the whole process of changing the Landmask and Lu_index converting the file to .cdl and then immediately converted file again for geo_em.d01.nc using the programs ncdump e ncgen. Replaces the original file and executed programs ungrib and metgrid. Until then everything worked fine, however when I run the programs real.exe and wrf.exe, the exit of the model is the map with lakes that were removed.

Ps: I checked the files geo_em.d01.nc and met_em.d01.nc for all times and all do not have the lakes.

Thanks for regards!

dmbrown1
Posts: 15
Joined: Tue Aug 10, 2010 9:02 pm

Re: Modification of land use and water temperatures

Post by dmbrown1 » Sat Jun 08, 2013 4:06 pm

If you're going to be modifying lakes in the netcdf files, then you need to modify three things: LANDMASK, LANDUSEF, and LUINDEX. LANDUSEF is the most important one. LANDUSEF contains a grid with the proportion of each land use type.

The easiest thing to do is make all your lakes 100% water (16), and 0% everything else, but you will have to keep track of where you are in the matrix because it is as wide as your domain, and contains 24 times as many rows as the height of your domain (for each land use type).

I would recommend adjusting the original 30s static land use files in wrfems/data/geog rather than editing the netcdf files, then geogrid can do the work for you (see the beginning of the topic...).

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