[ncl-talk] Abnormal data points

Thu Apr 15 13:38:34 MDT 2021

Dear Dennis,

Many thanks for the reply. Here I have attached the data file (meridional wind stress) and the script also. Please find the attachments.

Note: I use these stress data (meridional and zonal) to calculate wind stress curl. and then calculate the future minus present. Due to this line, my final output show a big difference which is not true along this line. This would be a really big help if you can help me out to solve the issue.

Millions of thanks and best regards,

Chathu

-----Original Messages-----
From:"Dennis Shea" <shea at ucar.edu>
Sent Time:2021-04-16 03:08:58 (Friday)
To: Chathurika <chatu at scsio.ac.cn>
Cc:
Subject: Re: Re: [ncl-talk] Abnormal data points

re:  "abnormal data values (in the original file)"

If the values are within a "normal" range but are outliers relative to adjacent local values, then there will be no standard function that can fix this. You may have to so manually set values.  This must be done *prior* to any regridding

I'll take quick look at the file. Please also send a clean simple script to read/plt the variable.

D

On Thu, Apr 15, 2021 at 12:56 PM Chathurika <chatu at scsio.ac.cn> wrote:

Dear Dennis,

Thank you so much for the reply. Even before, I use the regridding (ESMF_regrid), I plotted the data just to check. Still there is this line with abnormal data values (in the original file). I want to know whether there is any method which I can use to avoid this abnormal data points. How can I remove them? Because they are in the same range as normal data.

Thank you once again

and best regards,

Chathu

-----Original Messages-----
From:"Dennis Shea" <shea at ucar.edu>
Sent Time:2021-04-16 02:37:21 (Friday)
To: Chathurika <chatu at scsio.ac.cn>
Cc: "Soma Roy" <somaroy892 at gmail.com>, ncl-talk <ncl-talk at ucar.edu>
Subject: Re: [ncl-talk] Abnormal data points

If you have used the ESMF regrid functions for other variables and there is "no problem", I do not understand why there would be an issue with this variable. Something MUST be different.  It is up to you to determine just what the difference might be.

---------------

The 'line' looks like a single satellite trajectory.
---------------

Are the grid points missing? or, are they 'bad' values?

On Thu, Apr 15, 2021 at 11:18 AM Chathurika via ncl-talk <ncl-talk at mailman.ucar.edu> wrote:

Dear Soma,

it is NetCDF4, curvilinear data two dimensional coordinates (lat(i,j) lon(i,j) ). I regrided using ESMF regridding. (Note: I used ESMF regridding for all other variables also. I had no problem). 

Thank you so much.

Best 

Chathu

-----Original Messages-----
From:"Soma Roy" <somaroy892 at gmail.com>
Sent Time:2021-04-16 00:51:10 (Friday)
To: Chathurika <chatu at scsio.ac.cn>
Cc:
Subject: Re: [ncl-talk] Abnormal data points

What is the data file format?

Soma

On Thu, Apr 15, 2021, 22:10 Chathurika via ncl-talk <ncl-talk at mailman.ucar.edu> wrote:

Dear All,

Does anyone know which method I can use to remove (or interpolate) the data assigned with this abnormal line (which is in the black box of below figure)? 

If anyone can help me, this will be a big help. I can send the data file if you want to look at it.

Thank you in advance and best regards,

Chathu

Wickramage Chathurika Hemamali
Msc in Physical Oceanography
State Key Laboratory of Tropical Oceanography
South China Sea Institute of Oceanology
University of Chinese Academy of Science
China

Specialized in Oceanography and Marine Geology (Bachelor)
University of Ruhuna
Matara
Sri Lanka

Email : wickramagechathurika at rocketmail.com
chatu at scsio.ac.cn
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Wickramage Chathurika Hemamali
Msc in Physical Oceanography
State Key Laboratory of Tropical Oceanography
South China Sea Institute of Oceanology
University of Chinese Academy of Science
China

Specialized in Oceanography and Marine Geology (Bachelor)
University of Ruhuna
Matara
Sri Lanka

Email : wickramagechathurika at rocketmail.com
chatu at scsio.ac.cn
_______________________________________________
ncl-talk mailing list
ncl-talk at mailman.ucar.edu
List instructions, subscriber options, unsubscribe:
https://mailman.ucar.edu/mailman/listinfo/ncl-talk

Wickramage Chathurika Hemamali
Msc in Physical Oceanography
State Key Laboratory of Tropical Oceanography
South China Sea Institute of Oceanology
University of Chinese Academy of Science
China

Specialized in Oceanography and Marine Geology (Bachelor)
University of Ruhuna
Matara
Sri Lanka

Email : wickramagechathurika at rocketmail.com
chatu at scsio.ac.cn

Wickramage Chathurika Hemamali
Msc in Physical Oceanography
State Key Laboratory of Tropical Oceanography
South China Sea Institute of Oceanology
University of Chinese Academy of Science
China

Specialized in Oceanography and Marine Geology (Bachelor)
University of Ruhuna
Matara
Sri Lanka

Email : wickramagechathurika at rocketmail.com
chatu at scsio.ac.cn
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