[ncl-talk] Mottled output from gsn_csm_contour_map

Burakowski, Elizabeth Elizabeth.Burakowski at unh.edu
Thu Aug 17 11:07:08 MDT 2017 

​Thanks, Mary and Rick.  I expected some missing values where large water bodies existed, but the zoom-in Mary provided helped diagnose the issue.  I had a typo in the SnowDays function that looped over every other lat/lon instead of every lat/lon pair, lines 43-44 in subsetSNODAS_avgSNWDAYS.ncl​ should have been:


do nl=0,nlat-1,1

  do ml=0,mlat-1,1


instead of the original:


do nl=0,nlat-1,2

  do ml=0,mlat-1,2


The plot now looks as I would expect, mottling is gone. Thanks!


Liz.



Dr. Elizabeth A Burakowski
Research Assistant Professor
Earth Systems Research Center &
Institute for the Study of Earth, Oceans, and Space
University of New Hampshire
8 College Road Durham, NH 03824
603-862-1796
elizabeth.burakowski at unh.edu
________________________________
From: Mary Haley <haley at ucar.edu>
Sent: Thursday, August 17, 2017 12:58 PM
To: Rick Brownrigg
Cc: Burakowski, Elizabeth; ncl-talk at ucar.edu
Subject: Re: [ncl-talk] Mottled output from gsn_csm_contour_map

Hi Elizabeth,

I was working on a plot to show the very issue that Rick pointed out.  He's right that the data is pretty sparse.

Here's a modified version of your script that zooms in on the map a little, and draws filled dots in red where the data is missing, and in black otherwise.  You can see that each valid point is surrounded by missing points.

I had to zoom in on the map because the data is so dense.

--Mary


On Thu, Aug 17, 2017 at 10:31 AM, Rick Brownrigg <brownrig at ucar.edu<mailto:brownrig at ucar.edu>> wrote:
Hi,

I don't fully understand how the data are being computed, but the output file appears to be rather sparse, and that is likely the cause of the mottled appearance.  Attached is a "CellFill" version of the plot -- CellFill more nearly shows the grid cells.

And If I print sections of the ShowDays variable, its very typically like below; lots of missing-values interspersed with actual values.

I'm not much help here, but hopefully this provides some insight...
Rick

285,250)    -9999
(286,0)    6.2
(286,1)    -9999
(286,2)    7.4
(286,3)    -9999
(286,4)     8
(286,5)    -9999
(286,6)    7.9
(286,7)    -9999
(286,8)    10.22222
(286,9)    -9999
(286,10)    8.7
(286,11)    -9999
(286,12)     9
(286,13)    -9999
(286,14)     8
(286,15)    -9999
(286,16)    10.1
(286,17)    -9999
(286,18)    8.4
(286,19)    -9999
(286,20)    11
(286,21)    -9999
(286,22)    8.454545
(286,23)    -9999
(286,24)    11.5
(286,25)    -9999
(286,26)    9.363636
(286,27)    -9999
(286,28)     9
(286,29)    -9999
(286,30)    9.5
(286,31)    -9999
(286,32)    9.272727
(286,33)    -9999
(286,34)    9.3
(286,35)    -9999
(286,36)    8.5
(286,37)    -9999
(286,38)    8.2
(286,39)    -9999
(286,40)    7.636364
(286,41)    -9999


On Thu, Aug 17, 2017 at 9:37 AM, Burakowski, Elizabeth <Elizabeth.Burakowski at unh.edu<mailto:Elizabeth.Burakowski at unh.edu>> wrote:

Hi ncl-talk,


I am trying to create a map showing the number of days with snow depth greater than 200 mm from SNODAS files.  I have two scripts attached:


(1) subsetSNODAS_avgSNWDAYS.ncl

- subsets a smaller region from nation SNODAS domain,

- calculates the number of days with snow depth greater than user defined threshold

- calculates 2004-2017 average number of days with snow depth greater than threshold

- creates .nc file with 2004-2017 average

I have uploaded a few .nc source SNODAS files that serve as input to the subset script and the resulting 2004-2017 .nc file to the ncl-talk ftp site.


(2) plotNESNODAS_snowdays.ncl

- plots the output .nc file produced in subsetSNODAS_avgSNWDAYS.ncl

- this is a separate script because the subset script takes a while to run on the full time series for large regions.


Thanks,


Liz.



Dr. Elizabeth A Burakowski
Research Assistant Professor
Earth Systems Research Center &
Institute for the Study of Earth, Oceans, and Space
University of New Hampshire
8 College Road Durham, NH 03824
603-862-1796<tel:(603)%20862-1796>
elizabeth.burakowski at unh.edu<mailto:elizabeth.burakowski at unh.edu>

_______________________________________________
ncl-talk mailing list
ncl-talk at ucar.edu<mailto:ncl-talk at ucar.edu>
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk<https://urldefense.proofpoint.com/v2/url?u=http-3A__mailman.ucar.edu_mailman_listinfo_ncl-2Dtalk&d=DwMFaQ&c=c6MrceVCY5m5A_KAUkrdoA&r=JW2rHHzYnVYi6ZDBI-2JFMNSreDPLZO-wwOrczEnOlg&m=mbqQACvpKD_SdEZEWAtkUeePV-5K9I1V6PKH-xNjRwU&s=AIY6vClsvgpiKhjoJgxyskPzPhzWQCrSMMnljn9s23s&e=>



_______________________________________________
ncl-talk mailing list
ncl-talk at ucar.edu<mailto:ncl-talk at ucar.edu>
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk<https://urldefense.proofpoint.com/v2/url?u=http-3A__mailman.ucar.edu_mailman_listinfo_ncl-2Dtalk&d=DwMFaQ&c=c6MrceVCY5m5A_KAUkrdoA&r=JW2rHHzYnVYi6ZDBI-2JFMNSreDPLZO-wwOrczEnOlg&m=mbqQACvpKD_SdEZEWAtkUeePV-5K9I1V6PKH-xNjRwU&s=AIY6vClsvgpiKhjoJgxyskPzPhzWQCrSMMnljn9s23s&e=>


-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20170817/b56e65fe/attachment.html 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: NE_SnowDays_Nov-Apr_SNWZGT200_2004-2017.png
Type: image/png
Size: 107436 bytes
Desc: NE_SnowDays_Nov-Apr_SNWZGT200_2004-2017.png
Url : http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20170817/b56e65fe/attachment.png

More information about the ncl-talk mailing list