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20010328: Color fill vs. Contour smoothness

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  • Subject: 20010328: Color fill vs. Contour smoothness
  • Date: Wed, 28 Mar 2001 10:17:25 -0700
Mike,

Generally CONTUR = 3/3 produces good color filled contours. You can
try upping this to CONTUR=10/3.

What is the grid point spacing that you are using?
Are you creating the grid file with gdcfil or oagrid for the analysis.
You might be able to improve the analysis be decreasing the DELTAN
(eg increasing KXKY). The gdinfo output of the file header will give you
an ideaof DELTAN being used. If this is too large for the region, you
may get blocky results.

I'm assuming you are generating the  pressure analysis from surface
observations using oabsfc. Generally using GAMMA=.3 and NPASS = 2
produces a reasonably smooth field for contouring.

Steve Chiswell
Unidata User SUpport




>From: "Mike Hardiman" <address@hidden>
>Organization: UCAR/Unidata
>Keywords: 200103281548.f2SFmlL09944

>Hi,
>
>As part of Lyndon State College's met.dept. web site overhaul, I've been
>creating various contour/color fill charts for surface data.  Things
>have been going along "smoothly" with one exception: the Sea Level
>Pressure charts which are not "smooth" at all!  For some reason the
>color fills take on a wavy appearance, weaving around the black contour
>lines which are overlaid (example:
>http://apollo.lsc.vsc.edu/data/web/surface/slpne.gif ).
>
>I've played around with the values on CONTUR, but so far have been
>unsuccessful at getting the contour and color fill smoothness in line.
>Any help would be appreciated.  The input into GDCNTR is as follows:
>
>gdcntr << EOF
>
> GDFILE   = $GDFILE
> GDATTIM  = $DATE/$FILETIME
> GLEVEL   = 0
> GVCORD   = none
> PANEL    = 0/0
> SKIP     = 0
> SCALE    = 999
> GFUNC    = pmsl
> CTYPE    = F
> CINT     = 2/880/1070
> LINE     = 1/-1/1/2
> HILO     =
> HLSYM    =
> GVECT    =
> WIND     =
> REFVEC   =
> TITLE    = 1/-2/Sea Level Pressure Analysis (mb) ~ LSC Meteorology
> TEXT     = 1/3//HW
> CLEAR    = NO
> GAREA    = 39.8;-80.1;47.5;-67
> PROJ     = mer
> MAP      = 2//1
> \$MAPFIL = HIPOWO.CIA
> LATLON   = 0
> DEVICE   = GF|$SAVEDIR/slpne.gif|866;687
> STNPLT   =
> SATFIL   =
> RADFIL   =
> LUTFIL   =
> CONTUR   = 12
> SKIP     = 0
> FINT     = 2/880/1070
> FLINE    = 10-20;23-30
> CTYPE    = c/f
> CLRBAR= 1/V/LL/.002;.05//
>
>Thanks again.
>-Mike
>
>
>----------------------------------------------------------
>Mike Hardiman
>Student of Meteorology
>Lyndon State College ~ Lyndonville, VT
>