Chris,
since you want to plot 10 m wind, I think your probably need to check
something like u10m, v10m rather than ugrd, vgrd.
SC
On Wed, Jul 8, 2009 at 4:46 PM, Mary Haley<haley_at_ucar.edu> wrote:
>
> Dave B pointed out that my answer to the wind speed/direction was the
> opposite of what you want. I believe Dave answered this question
> correctly.
>
> --Mary
>
> On Wed, 8 Jul 2009, Mary Haley wrote:
>
>> Hi Chris,
>>
>> It's possible that the variable is not called exactly "UGRD" on the
>> file.
>>
>> What does the following report:
>>
>> ncl_filedump 10m_Winds/2008-12_10m-wind.grb
>>
>> or
>>
>> ncl_filedump 10m_Winds/2008-12_10m-wind.grb | grep -i ugrd
>>
>> Do you see a variation of "UGRD"?
>>
>> As for your other questions:
>>
>>> 2) If anyone could offer some code examples that would fill an array of
>>> values (over all [or some] times) from the horizontal grid that are
>>> valid for a given lat/lon that would be really helpful.
>>
>> Can you elaborate here? I'm not sure what you mean by "from the horizontal
>> grid that are valid"...
>>
>>> 3) Are there any built-in functions (or contributed ones) that will
>>> convert my U and V components into Speed and Direction?
>>
>> This was asked once before on ncl-talk. See:
>>
>> http://www.ncl.ucar.edu/Support/talk_archives/2009/0381.html
>>
>>
>> --Mary
>>
>> On Wed, 8 Jul 2009, Christopher G. Herbster wrote:
>>
>>> Hi all,
>>>
>>> I have downloaded 10m winds (U and V) in grib format and I am having
>>> trouble reading the files.
>>>
>>> I have cat'ed both components into a single file. An ultimate goal is
>>> to extract wind information for an arbitrary location and use that
>>> information to build a wind rose.
>>>
>>> 1) When I try to read in the variables from the file I get an error that
>>> says they don't exist or there is a problem with the file.
>>>
>>> ;***************************************
>>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
>>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/wind_rose.ncl"
>>> ;
>>> ; Need the next one for the read functions
>>> load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"
>>>
>>> ;***************************************
>>> begin
>>> ;
>>> fname = "10m_Winds/2008-12_10m-wind.grb"
>>> ;
>>> ;
>>> ; Open file to read
>>> infile = addfile(fname,"r") ; Open GRIB file to read
>>> ;
>>> ; Fill the U and V arrays
>>> ugrd = infile->UGRD
>>> vgrd = infile->VGRD
>>>
>>> usize = dimsizes(ugrd)
>>> print ("usize is " + usize)
>>>
>>>
>>> end
>>>
>>> -----------
>>>
>>> This yields:
>>>
>>> $ ncl read_reanalysis_windrose.ncl
>>> Copyright (C) 1995-2007 - All Rights Reserved
>>> University Corporation for Atmospheric Research
>>> NCAR Command Language Version 4.3.0
>>> The use of this software is governed by a License Agreement.
>>> See http://www.ncl.ucar.edu/ for more details.
>>> fatal:Either file (infile) isn't defined or variable (UGRD) is not a
>>> variable in the file
>>> fatal:Execute: Error occurred at or near line 26 in file
>>> read_reanalysis_windrose.ncl
>>>
>>> ----------
>>>
>>> wgrib says this is what is in the file:
>>>
>>> $ wgrib 10m_Winds/2008-12_10m-wind.grb -v
>>> 1:0:D=2008120100:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u wind [m/s]
>>> 2:20388:D=2008120106:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u wind
>>> [m/s]
>>> 3:40776:D=2008120112:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u wind
>>> [m/s]
>>> 4:61164:D=2008120118:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u wind
>>> [m/s]
>>> 5:81552:D=2008120200:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u wind
>>> [m/s]
>>> 6:101940:D=2008120206:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 7:122328:D=2008120212:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 8:142716:D=2008120218:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 9:163104:D=2008120300:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 10:183492:D=2008120306:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> <... snip ...>
>>> 120:2428428:D=2008123018:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 121:2448816:D=2008123100:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 122:2469204:D=2008123106:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 123:2489592:D=2008123112:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 124:2509980:D=2008123118:UGRD:10 m above gnd:kpds=33,105,10:6hr fcst:"u
>>> wind [m/s]
>>> 125:2530368:D=2008120100:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 126:2550756:D=2008120106:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 127:2571144:D=2008120112:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 128:2591532:D=2008120118:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 129:2611920:D=2008120200:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 130:2632308:D=2008120206:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 131:2652696:D=2008120212:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 132:2673084:D=2008120218:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 133:2693472:D=2008120300:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 134:2713860:D=2008120306:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> <... snip ...>
>>> 244:4958796:D=2008123018:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 245:4979184:D=2008123100:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 246:4999572:D=2008123106:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 247:5019960:D=2008123112:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>> 248:5040348:D=2008123118:VGRD:10 m above gnd:kpds=34,105,10:6hr fcst:"v
>>> wind [m/s]
>>>
>>>
>>> ------------
>>>
>>> Any help in getting past this fundamental point is greatly appreciated.
>>>
>>>
>>> 2) If anyone could offer some code examples that would fill an array of
>>> values (over all [or some] times) from the horizontal grid that are
>>> valid for a given lat/lon that would be really helpful.
>>>
>>>
>>> 3) Are there any built-in functions (or contributed ones) that will
>>> convert my U and V components into Speed and Direction?
>>>
>>>
>>> Thanks in advance for any help!
>>>
>>> Cheers,
>>> Chris Herbster
>>>
>>> --
>>>
>>> Dr. Christopher G. Herbster
>>> Associate Professor
>>> Director of Science and Technology
>>> for the ERAU Weather Center
>>> Applied Aviation Sciences
>>> Embry-Riddle Aeronautical Univ.
>>> 600 S. Clyde Morris Blvd.
>>> Daytona Beach, FL 32114-3900
>>>
>>> 386.226.6444 Office
>>> 386.226.6446 Weather Center
>>> http://wx.erau.edu/
>>>
>>> Schedule at: http://wx.erau.edu/faculty/herbster/Schedules/
>>>
>>>
>>> _______________________________________________
>>> ncl-talk mailing list
>>> List instructions, subscriber options, unsubscribe:
>>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>>
>> _______________________________________________
>> ncl-talk mailing list
>> List instructions, subscriber options, unsubscribe:
>> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>>
> _______________________________________________
> ncl-talk mailing list
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk
>
Received on Wed Jul 08 2009 - 14:56:10 MDT
This archive was generated by hypermail 2.2.0 : Mon Jul 13 2009 - 20:56:19 MDT