Re: [cf-satellite] NetCDF gdal question

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ArcGIS can read netcdf files these days.  Have you tried just importing the 
netcd file into ArcGIS instead of making it into a geoTIFF.  IMO,  if ArcGOS is 
going to insist that everything is (-180, 180) then when they read invalid 
files they should do the necessary conversions/wrapping.  I think to do so 
would take about 3 lines of code.

-Roy

> On Jun 13, 2017, at 12:08 PM, Doug Fowler <dfowler@xxxxxxxxx> wrote:
> 
> Hi Roy,
> Thanks for the quick reply. ArcGIS is a popular tool among our users as are 
> GeoTIFF files. So I guess this one test was for to produce good GeoTIFF files 
> from the NetCDF files. The problem is visualizing the data 180 degrees from 
> where it should be. I don't know if it was run through a cf checker, but can 
> check with the data producer.
> 
> Thanks again,
> Doug
> 
> We have written
> 
> On 6/13/2017 11:05 AM, Roy Mendelssohn - NOAA Federal wrote:
>> Hi Doug:
>> 
>> I thought GDAL had fixed this problem.  it comes from just assuming what the 
>> latitudes and longitudes are,  rather than reading in from the file.  So for 
>> example,  GDAL used to assume latitudes ran north to south,  even when they 
>> didn't.  Also,, they are not set to handle data where longitudes are (0, 
>> 360).  ArcGIS has the same problem because I believe they just use GDAL.
>> 
>> Can I also ask what exactly you are trying to achieve, and what you view as 
>> the "problem".  Given that HDFView and Panoply are reading them fine,  
>> suggests that they are standard netcdf files.  There are checkers to see if 
>> they are also valued CF netcdf files.  IMO,  if they are,  then what you are 
>> seeing is   a GDAL/ArcGIS problem,  which you should probably take up with 
>> them.
>> 
>> -Roy
>> 
>>> On Jun 13, 2017, at 9:18 AM, Doug Fowler <dfowler@xxxxxxxxx> wrote:
>>> 
>>> Hello,
>>>  I work at a data center (NSIDC) in Boulder and we are reviewing some new 
>>> NetCDF data that we'll archive. This is satellite data and is a fairly low 
>>> level swath product. The geolocation data (lat/lons) is linked to the 
>>> science data within each file.
>>> 
>>> In HDFView and Panoply the data seems to display fine, but using ArcGIS, 
>>> QGIS, and gdal, the data is 180 degrees off.
>>> As an example, a file that is over Japan show up over the Atlantic in 
>>> ArcGIS.
>>> 
>>> One of my team ran some through gdal, here are his comments;
>>> It appears that GDAL has the same problem as ArcGIS, namely that when I 
>>> create a GeoTIFF using gdal_translate extracting any band in 
>>> VNP10.A2015183.1242.001.2017157163531.nc, the longitude values for each GCP 
>>> in the GeoTIFF are 180 degrees too large.
>>> 
>>> The first GCP is:
>>> GCP[  0]: Id=1, Info=
>>>          (0.5,0.5) -> (205.183015823364,62.1505355834961,0)
>>> I believe it should be:
>>> GCP[  0]: Id=1, Info=
>>>          (0.5,0.5) -> (25.183015823364,62.1505355834961,0)
>>> 
>>> 
>>> We've basically exhausted things to try here. I was told that you might 
>>> have some suggestions of things to look at or try to help determine what is 
>>> causing this problem.
>>> 
>>> Any ideas or  information is appreciated,
>>> Doug Fowler
>>> 
>>> -- 
>>> Doug Fowler, MODIS, VIIRS & ICESat Team Lead
>>> National Snow & Ice Data Center
>>> University of Colorado at Boulder
>>> UCB 449, Boulder, CO  80309
>>> ph (303)735-1357; fax (303)492-2468
>>> email: dfowler@xxxxxxxxx
>>> 
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>> **********************
>> "The contents of this message do not reflect any position of the U.S. 
>> Government or NOAA."
>> **********************
>> Roy Mendelssohn
>> Supervisory Operations Research Analyst
>> NOAA/NMFS
>> Environmental Research Division
>> Southwest Fisheries Science Center
>> ***Note new street address***
>> 110 McAllister Way
>> Santa Cruz, CA 95060
>> Phone: (831)-420-3666
>> Fax: (831) 420-3980
>> e-mail: Roy.Mendelssohn@xxxxxxxx www: http://www.pfeg.noaa.gov/
>> 
>> "Old age and treachery will overcome youth and skill."
>> "From those who have been given much, much will be expected"
>> "the arc of the moral universe is long, but it bends toward justice" -MLK Jr.
>> 
> 
> -- 
> Doug Fowler, MODIS, VIIRS & ICESat Team Lead
> National Snow & Ice Data Center
> University of Colorado at Boulder
> UCB 449, Boulder, CO  80309
> ph (303)735-1357; fax (303)492-2468
> email: dfowler@xxxxxxxxx
> 

**********************
"The contents of this message do not reflect any position of the U.S. 
Government or NOAA."
**********************
Roy Mendelssohn
Supervisory Operations Research Analyst
NOAA/NMFS
Environmental Research Division
Southwest Fisheries Science Center
***Note new street address***
110 McAllister Way
Santa Cruz, CA 95060
Phone: (831)-420-3666
Fax: (831) 420-3980
e-mail: Roy.Mendelssohn@xxxxxxxx www: http://www.pfeg.noaa.gov/

"Old age and treachery will overcome youth and skill."
"From those who have been given much, much will be expected" 
"the arc of the moral universe is long, but it bends toward justice" -MLK Jr.



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