Open data? GOES16 legacy temperature profile issues
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GOES16 legacy temperature profiles have weird offsets when I load the netcdf file in many programs (I am up to date with netcdf4 libraries). For example, in the attached file I show a profile of the temperature at point nx=500, ny=500 of the file listed in the title of the figure. Offset occurs from points 1 to 37, and 86 to 97. Is this issue known for these ABI products? The figure shows a profile from aws depository s3://noaa-goes16/ABI-L2-LVTPF/2020/255/00/OR_ABI-L2-LVTPF-M6_G16_s20202550000196_e20202550009504_c20202550011454.nc
One possible problem I see is that the valid range for the LVM variable is "LVM:valid_range = 0s, -6s ;" I have never seen this before. Any suggestions?
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Hello, I am going to try and summarize a bit of the info I've gotten from NOAA scientists.
One of the scientists went ahead and took a deeper look into this. They were able to read and plot the data from a recent LVTF file (s3://noaa-goes16/ABI-L2-LVTPF/2022/294/00/OR_ABI-L2-LVTPF-M6_G16_s20222940000204_e20222940009512_c20222940011470.nc), and it does not show the same strange offsets. Granted this is not the exact same file as in the example provided, but there have not been any changes to the product output since 2020. The analysis was done manually in IDL, so they are curious if there is something about the software you are using that is not converting the scaled integers properly.
Also, it turns out that the valid_range issue you brought up is one that was addressed via a software update in late 2020 which converted all of the ABI L2 products to use native unsigned integers. This update came after the product file in question which is from September 2020. For a signed short (values of -32768 to 32768), a valid range of 0s, -6s is equivalent to 0, 35530 as the data wraps around to negative values once it reaches its max of 32768.