Re: SH polar contour not appear

Hi Ahmed,

Thanks for providing a script and a link to your data.

The problem is that your x and y coordinate arrays, which are supposed to represent longitude and latitude values, do not have a "units" attribute to indicate that these are degrees_east and degrees_north.

I fixed this by adding "units" attributes:

elv&x@units = "degrees_east"
elv&y@units = "degrees_north"

Your "elv" array has "NaN" as a missing value, which will not work in NCL. It appears you don't have any NaNs in your data, so you're okay for now. But, in the future, you might want to consider changing this value to, say, the default missing value for the type of "elv":

elv@_FillValue = default_fillvalue(typeof(elv)) ; Replace NaN w/a valid value

Please see the attached modified script and resultant PNG file. I didn't try changing the contour levels, so this plot can probably be improved by selecting better contour levels to go with the color map you've chosen.

--Mary

On Sep 19, 2012, at 5:08 AM, Ahmed Lasheen wrote:

> Hello
> I am trying to plot the terrain in polar steographic projection . The contour in northen hemispher contour is plotted, but the contour in southern hemisphere is not
> plotted(i.e. rest@gsnPolar = "NH" contour is plotted , rest@gsnPolar = "SH" contour is not plotted)
> The data that i used is ETOPO2v2 Global Gridded 2-minute Database http://www.ngdc.noaa.gov/mgg/global/etopo2.html.
> I have attached the script , NH terrain contour , SH terrain contour .
> thanks in advance
>
> --
> ===============
> Ahmed Lasheen
> Junior researcher at Cairo Numerical Weather Prediction Center (CNWPC)
> Egyptian Meteorological Authority(EMA)
> Cairo,Egypt
> ===============
>
> <polar.ncl><NH.png><SH.png>_______________________________________________
> 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 Sep 19 09:51:25 2012