[ncl-talk] RUC2-Analysis Data Incorrectly Interpolated to Surface

[Michelle Serino]

My apologies. After switching back and forth between my 13-km script and
the 25-km script, I was mixed up. Thanks for your help.

Best regards,

Michelle

Michelle Serino
M.S. Candidate
Texas A&M University
Atmospheric Sciences Dept.
Eller O&M, Suite 1017
College Station, TX 77843
(484) 769-0949

On Sun, Jan 31, 2016 at 8:30 AM, Dennis Shea <shea at ucar.edu> wrote:

> You had print statements in the code. You should have looked at the output.
>
> p  = f->lv_ISBL3                                 ; hPa
> print(p)
> t
>
> You had
>
> [snip]
>      p = int2flt(f->lv_ISBL3)             ; <=== hPa
>     psfc = f->PRES_252_SFC        ; "ground" pressure => pressure  (Pa)
>         ; change units and calculate needed variables
>     psfc = psfc/100
>     psfc at units = "hPa"
>
>     p = p/100                                   ; NO!  why
>     p at units = "hPa"                       ; p was in hPa
> [snip]
>
> Note: there is no need for:
>     p = int2flt(f->lv_ISBL3)
> the following is fine
>     p = f->lv_ISBL3
>
> See attachment
>
>
> On Fri, Jan 29, 2016 at 3:12 PM, Michelle Serino <mmserino at tamu.edu>
> wrote:
>
>> Hi Dennis,
>>
>> Thank you for getting back to me; your advice helped!  I am now trying to
>> adapt your advice to a separate script I have for the 25-km RUC2-Analysis,
>> and I receive the error:
>>
>> fatal:Le: Number of dimensions do not match, can't continue
>>
>> fatal:["Execute.c":8575]:Execute: Error occurred at or near line 97 in
>> file sounding25.ncl
>>
>>
>> I did my best to make sure that I converted the variable names to those
>> of the 25-km format and that I didn't make any other simple mistakes.  I
>> could easily have overlooked something, though.  Again, my script is
>> attached, and the direct link to the 25-km data is below. Thank you for
>> your continued help!
>>
>>
>>
>> https://www.dropbox.com/s/fhq2s4o8vp0yiol/ruc2anl_252_20090605_1200_000.grb?dl=0
>>
>>
>> Best regards,
>>
>>
>> Michelle Serino
>>
>> Michelle Serino
>> M.S. Candidate
>> Texas A&M University
>> Atmospheric Sciences Dept.
>> Eller O&M, Suite 1017
>> College Station, TX 77843
>> (484) 769-0949
>>
>> On Thu, Jan 28, 2016 at 8:45 PM, Dennis Shea <shea at ucar.edu> wrote:
>>
>>> A key is  the 'level_type' attribute associated with the pressure
>>> variables (PRES_). There are numerous PRES_ variables. In particular,
>>>
>>>       float PRES_P0_L1_GLC0 ( ygrid_0, xgrid_0 )
>>>          center :       US National Weather Service - NCEP (WMC)
>>>          production_status :    Operational products
>>>          long_name :    Pressure
>>>          units :        Pa
>>>          _FillValue :   1e+20
>>>          coordinates :  gridlat_0 gridlon_0
>>>          grid_type :    Lambert Conformal can be secant or tangent,
>>> conical or bipolar
>>>          parameter_discipline_and_category :    Meteorological products,
>>> Mass
>>>          parameter_template_discipline_category_number :        ( 0, 0,
>>> 3, 0 )
>>>          level_type :   Ground or water surface
>>> <*******************************************
>>>          level :         0
>>>          forecast_time :        0
>>>          forecast_time_units :  hours
>>>          initial_time : 06/05/2009 (12:00)
>>>
>>> It is a guess that this is the surface pressure (psfc). All pressure
>>> levels > psfc must be extrapolated. [ *Extrapolation is always dangerous!]
>>>
>>> The 'ind' function can be used to get all 'valid' levels [ p<psfc ]. Try
>>> attached.
>>>
>>> Cheers
>>>
>>>
>>> On Thu, Jan 28, 2016 at 11:47 AM, Michelle Serino <mmserino at tamu.edu>
>>> wrote:
>>>
>>>> Good afternoon,
>>>>
>>>> I am plotting RUC2-Analysis data on a skew-T.  Because this is analysis
>>>> data, it seems that the data are always interpolated to the 1000-mb
>>>> surface, regardless of the chosen location.  For example, in a high
>>>> elevation location like Denver, the data extend down to 1000 mb, which is
>>>> unrealistic.  This creates incorrect surface values, which results in a
>>>> very incorrect value of surface CAPE.
>>>>
>>>> I am wondering if, while still plotting on a skew-T, there is a way to
>>>> specify the data that is plotted.  Or, if there is another, more realistic,
>>>> way around this.  With a real sounding, I would not have this problem, so I
>>>> am sure there is a way to fix this for the analysis data.  I have attached
>>>> the script I am using, along with its plot and an observed sounding for the
>>>> same location (Denver).  The direct link to the analysis data I am using is
>>>> provided below.  I appreciate any help!
>>>>
>>>>
>>>> https://www.dropbox.com/s/qpe96hmhh9hsi0h/ruc2anl_130_20090605_1200_000.grb2?dl=0
>>>>
>>>> Best regards,
>>>>
>>>> Michelle Serino
>>>>
>>>> Michelle Serino
>>>> M.S. Candidate
>>>> Texas A&M University
>>>> Atmospheric Sciences Dept.
>>>> Eller O&M, Suite 1017
>>>> College Station, TX 77843
>>>> (484) 769-0949
>>>>
>>>> _______________________________________________
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>>>> ncl-talk at ucar.edu
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>>>>
>>>>
>>>
>>
>
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