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[GEMPAK #HWF-513769]: NSHARP - code documentation for "total shear" ?

Larry,

Correct, they are scaling by 10E-4 in the display.

The wind_shear() routine is called using the depth in meters from the top
and bottom of the layer, so there is a 10E3 factor to convert to the km depth 
in the table. Not sure why they chose the extra "10" they are dividing from
(other than making the numbers easier to read?).

Steve Chiswell
Unidata User Support

> Hello Steve,
> 
> Thanks for the paths and program names.  From a quick perusal of the code
> and your comments below, it appears that
> 
> 1. "TOT SHR" is in fact not "total shear" (or length of the hodograph) but
> what is more commonly referred to as "bulk shear" (e.g. Bunkers et al. 2002,
> 21SLS) in the defined layer (e.g., SFC - 6 km).
> 
> 2. The units appear to be 10E-4 s-1
> 
> If correct, that clears up the confusion on our end.
> 
> Thanks,
> Larry
> 
> -----Original Message-----
> From: Unidata GEMPAK Support
> [mailto:address@hidden]
> Sent: Friday, February 09, 2007 5:34 PM
> To: address@hidden
> Cc: address@hidden; address@hidden
> Subject: [GEMPAK #HWF-513769]: NSHARP - code documentation for "total shear"
> ?
> 
> Larry,
> 
> The code calculating wind shear in NSHARP is found in the source
> distribution
> under the $GEMPAK/source/programs/gui/nsharp/winds.c routine "wind_shear",
> 
> The quantity being printed in the table (rounded for display) is being
> printed
> in the xwvid3.c routine (same directory as above) where the magnitude of
> shear is being divided by the depth of the layer.
> 
> The wind_shear routine is interpolating the winds to the top level of
> the calculation and then calculating the difference in components in order
> to arrive at the magnitude.
> 
> Steve Chiswell
> Unidata User Support
> 
> 
> > Greetings,
> >
> >
> >
> > Is it possible to see the code or documentation for how "total shear" (TOT
> > SHR) is calculated and displayed in NSHARP?  Based on some past use in
> class
> > and research, the definition and units for "total shear" in NSHARP and how
> > this quantity compares to usage in the literature/conference papers are
> not
> > entirely clear to me.   The quantity (total shear) is calculated in
> various
> > layers and presented in tabular form towards the bottom of text output
> page
> > 2 (i.e., right most column of values in the bottom "environmental shear"
> > table).  It is labeled "TOT SHR."   Any clarification you can provide
> would
> > be much appreciated.  Thanks for your help!
> >
> >
> >
> > Best regards,
> >
> > Larry
> >
> >
> >
> > __________________________________
> > Dr. Larry Carey
> > Assistant Professor
> > Department of Atmospheric Sciences
> > Texas A&M University
> > 3150 TAMU
> > College Station, TX 77843-3150
> > Phone: 979-847-9090
> > Fax: 979-862-4466
> > E-mail: address@hidden
> >
> > Internet:http://www.met.tamu.edu/people/faculty/carey.php
> > ________________________________
> >
> >
> >
> >
> >
> 
> 
> Ticket Details
> ===================
> Ticket ID: HWF-513769
> Department: Support GEMPAK
> Priority: Normal
> Status: Closed
> 
> 
> 
> 


Ticket Details
===================
Ticket ID: HWF-513769
Department: Support GEMPAK
Priority: Normal
Status: Closed