[gradsusr] Eurocentric global map
Cara Duckworth
cara.duckworth at keble.ox.ac.uk
Tue Nov 19 15:01:30 EST 2013
Hi all,
Thank you so much for your help!
As Andrew suggested, moving the 'set lon -180 180' command to the top of the script, right after opening the file, has proved successful!
Cara
On 19 Nov 2013, at 18:19, "James T. Potemra" <jimp at hawaii.edu>
wrote:
> Chuck/Cara:
>
> If you define a variable from lon=0 to 360, then try and plot it
> from 180 to 540, you will only get the part 180 to 360 (where
> it is defined). If instead you define the variable from 180 to 540
> you should be able to plot it over that range.
>
> All this assumes that the variable's longitude is continuously
> defined across 360. Cara, if you attach your descriptor file we
> can figure this out. Or, check the XDEF line; if your variables
> are defined from 0 to 360, check the number of points and
> X-increment to see if continuous. For example, if you have
> something like:
> XDEF 360 LINEAR 0.5 1.0
> x=1 corresponds to lon=0.5, x=2 corresponds to lon=1.5, etc
> to x=360 corresponds to lon=359.5. So, x=361 will match with
> 360.5 which is the same as 0.5 and x=1. So, in this case the
> longitudes are continuous.
>
> Jim
On 19 Nov 2013, at 17:53, Andrew Friedman <andfried at berkeley.edu>
wrote:
> Following up: Try moving the command ‘set lon -180 180’ to near the top of your script, right after opening the file.
>
> On 11/19/13 7:27 AM, Charles Seman - NOAA Federal wrote:
>> Jim, Cara,
>>
>> I just tried plotting the variable *defined* for lon = (0,360) for lon =
>> (180,540), and now the *right* half of the map is missing. It appears
>> that *defined* variables are only valid on the domain for which they are
>> defined, while *dataset* variables can be plotted for domains outside of
>> the domain specified in the metadata (or data descriptor file).
>> Apparently, GrADS knows how to "wrap" in the longitude direction for a
>> dataset variable, but does not do this for a defined variable...
>>
>> Can you try defining the variable of interest for lon = (-180,180) or as
>> Alan suggested lon = (-170,190), or whatever domain on which you wish to
>> plot it? Another alternative would be to write out the variable defined
>> on lon = (0,360) to a dataset, open that dataset, and work with that
>> dataset variable...
>>
>> Hope this helps,
>> Chuck
>>
>> On 11/19/2013 11:22 AM, James T. Potemra wrote:
>>> Cara:
>>>
>>> Can you try 'set lon 180 540'? This should work if your longitude
>>> values are continuous.
>>>
>>> Jim
>>> On 11/19/13 5:44 AM, Cara Duckworth wrote:
>>>> Hi Chuck,
>>>>
>>>> Thanks for your response. Yes, I just checked: lon = 0,360.
>>>>
>>>> Is there a way that I can change this so that I can plot the global map from lon -180 to 180 (with Europe in the middle)?
>>>> When I plot it at lon=0,360, the map is fine but America is in the centre and I need Europe in the centre.
>>>>
>>>> Best,
>>>> Cara
>>>>
>>>> On 19 Nov 2013, at 15:15, Charles Seman - NOAA Federal <charles.seman at noaa.gov> wrote:
>>>>
>>>>> Cara,
>>>>>
>>>>> Check to see if the variable you're trying to plot has been defined
>>>>> locally in GrADS and what the longitude range is for it. I was able to
>>>>> replicate the issue by defining a local GrADS variable for lon = (0,360)
>>>>> and then when displaying it for lon = (-180,180) the left half was missing.
>>>>>
>>>>> Hope this helps,
>>>>> Chuck
>>>>>
>>>>> On 11/19/2013 09:33 AM, Cara Duckworth wrote:
>>>>>> Thanks Alan and Chris,
>>>>>>
>>>>>> I'm still having troubles plotting the map.
>>>>>> When I use "set lon -180 180", one half of the plot is missing (see
>>>>>> image attached)
>>>>>>
>>>>>> Without this instruction the map is fine (with all data displayed),
>>>>>> though Europe is not in the centre.
>>>>>> Any ideas as to what I have done wrong?
>>>>>>
>>>>>> Best,
>>>>>> Cara
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>> On 19 Nov 2013, at 13:25, Bill Reilly <bill_reilly at compuserve.com
>>>>>> <mailto:bill_reilly at compuserve.com>> wrote:
>>>>>>
>>>>>>> Alan:
>>>>>>>
>>>>>>> I think you mean:
>>>>>>>
>>>>>>> set lon -180 180
>>>>>>>
>>>>>>> --
>>>>>>>
>>>>>>> Bill Reilly
>>>>>>> www.passageweather.com <http://www.passageweather.com>
>>>>>>>
>>>>>>> On 11/19/2013 1:30 PM, Alan Robock wrote:
>>>>>>>> Dear Cara
>>>>>>>>
>>>>>>>> set lat -180 180
>>>>>>>>
>>>>>>>> or if you don't want to split Alaska:
>>>>>>>>
>>>>>>>> set lat -170 190
>>>>>>>> Alan Robock
>>>>>>>>
>>>>>>>> Alan Robock, Distinguished Professor
>>>>>>>> Editor, Reviews of Geophysics
>>>>>>>> Director, Meteorology Undergraduate Program
>>>>>>>> Department of Environmental Sciences Phone: +1-848-932-5751
>>>>>>>> Rutgers University Fax: +1-732-932-8644
>>>>>>>> 14 College Farm Road E-mail:robock at envsci.rutgers.edu
>>>>>>>> New Brunswick, NJ 08901-8551 USAhttp://envsci.rutgers.edu/~robock
>>>>>>>> http://twitter.com/AlanRobock
>>>>>>>> Watch my 18 min TEDx talk athttp://www.youtube.com/watch?v=qsrEk1oZ-54
>>>>>>>>
>>>>>>>> On 11/19/2013 6:54 AM, Cara Duckworth wrote:
>>>>>>>>> Dear users,
>>>>>>>>>
>>>>>>>>> I need to plot a global map, which is centred on the Prime Meridian
>>>>>>>>> (i.e. a Eurocentric map).
>>>>>>>>> Currently, the Prime Meridian is at either edge of my plot. How do I
>>>>>>>>> change this?
>>>>>>>>>
>>>>>>>>> Thanks,
>>>>>>>>> Cara
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> _______________________________________________
>>>>>>>>> gradsusr mailing list
>>>>>>>>> gradsusr at gradsusr.org
>>>>>>>>> http://gradsusr.org/mailman/listinfo/gradsusr
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> gradsusr mailing list
>>>>>>>> gradsusr at gradsusr.org
>>>>>>>> http://gradsusr.org/mailman/listinfo/gradsusr
>>>>>>> _______________________________________________
>>>>>>> gradsusr mailing list
>>>>>>> gradsusr at gradsusr.org
>>>>>>> http://gradsusr.org/mailman/listinfo/gradsusr
>>>>>>
>>>>>> _______________________________________________
>>>>>> gradsusr mailing list
>>>>>> gradsusr at gradsusr.org
>>>>>> http://gradsusr.org/mailman/listinfo/gradsusr
>>>>>>
>>>>> --
>>>>>
>>>>> Please note that Charles.Seman at noaa.gov should be considered my NOAA
>>>>> email address, not cjs at gfdl.noaa.gov.
>>>>>
>>>>> ********************************************************************
>>>>> Charles Seman Charles.Seman at noaa.gov
>>>>> U.S. Department of Commerce / NOAA / OAR
>>>>> Geophysical Fluid Dynamics Laboratory voice: (609) 452-6547
>>>>> 201 Forrestal Road fax: (609) 987-5063
>>>>> Princeton, NJ 08540-6649 http://www.gfdl.noaa.gov/~cjs/
>>>>> ********************************************************************
>>>>>
>>>>> "The contents of this message are mine personally and do not reflect any
>>>>> official or unofficial position of the United States Federal Government,
>>>>> the United States Department of Commerce, or NOAA."
>>>>> _______________________________________________
>>>>> gradsusr mailing list
>>>>> gradsusr at gradsusr.org
>>>>> http://gradsusr.org/mailman/listinfo/gradsusr
>>>> _______________________________________________
>>>> gradsusr mailing list
>>>> gradsusr at gradsusr.org
>>>> http://gradsusr.org/mailman/listinfo/gradsusr
>>> _______________________________________________
>>> gradsusr mailing list
>>> gradsusr at gradsusr.org
>>> http://gradsusr.org/mailman/listinfo/gradsusr
>>>
>
> _______________________________________________
> gradsusr mailing list
> gradsusr at gradsusr.org
> http://gradsusr.org/mailman/listinfo/gradsusr
More information about the gradsusr
mailing list