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Daily-OSST new convention issues

PostPosted: Fri Dec 18, 2020 12:50 am
by thomascap
Hi everyone,

We are facing an issue with regard to the convention’s differences between Daily-OSST at the date of 2017-03-01 and 2017-04-01.
For those files the conventions are different, CF-1 and CF-1.6 respectively.
// global attributes:
:Conventions = "CF-1.0" ;
:title = "Daily-OI-V2, Final, Data (Ship, Buoy, AVHRR: NOAA19, METOP, NCEP-ice)" ;
:History = "Version 2.0" ;
:creation_date = "2017-03-16 11:10" ;
:Description = "Reynolds, et al.(2007) Daily High-resolution Blended Analyses. Available at Climatology is based on 1971-2000 OI.v2 SST, Satellite data: Navy NOAA19 METOP AVHRR, Ice data: NCEP ice" ;
:Source = "NOAA/National Climatic Data Center" ;
:Contact = "(censored-word) Reynolds, email: & Chunying Liu, email:" ;
// global attributes:
:Conventions = "CF-1.6" ;
:title = "NCEI Daily-OISST-V2 based mainly on AVHRR, Final" ;
:history = "Version 2.0" ;
:creation_date = "2017-04-19 16:13" ;
:source_data = "NCEP GTS,AVHRR19,MetOpA,NCEP ICE" ;
:source = "NOAA/National Centers for Environmental Information" ;
:contact = "oisst-help, email:" ;

As we are having issues with the CF-1.6, is any possibility to convert the files (CF-1.6 ; 1.6Mo) to the old version (CF-1 ; 7.9Mo) ?

Thank you very much for your help in this matter.
Best regards


Re: Daily-OSST new convention issues

PostPosted: Mon Dec 21, 2020 10:16 am
by wenhaoli
Hi Thomas,

Thank you for your inquiry.

Could you provide us the data short or long name? If you have the data access URL, it will be even better. We need to know exactly which SST dataset you have discovered the issue.



Re: Daily-OSST new convention issues

PostPosted: Tue Dec 22, 2020 5:43 am
by thomascap
Hi Wenhao,

Thanks for your reply.
There is no issue concerning the dataset.

The issue comes from the new "version" since 2017-04-01.
Before that date the convention is CF-1.0 (7.9Mo for a daily file) ...

After that (since 2017-04-01) the convention is CF-1.6 (1.6Mo for a daily file). ...

Is there a possibility to obtain teh dataset since 2017-04-01 in the old covention style? Or an easy way to convert those files in the convention CF-1.6 in the old one?
Indeed with our tool the new style can't be read... Is it due to format? netcdf-3/CDM for the old convention and Hierarchical Data Format, version 5 for the new convention?

Thanks for your help

Re: Daily-OSST new convention issues

PostPosted: Tue Dec 22, 2020 1:11 pm
by edward.m.armstrong
Hi Thomas,

We do not distribute the dataset that you refer to. We have a similar dataset with the identical SST but formatted to GHRSST specifications. You can find it here: ... s=&values=

It is in a netCDF4 data format but your software should be able to read it. In fact the issue you describe sounds confusing because netCDF3 is really the same as netCDF4 "classic" which some netCDF software readers report as HDF5. NetCDF4 is truly a HDF5 file.

The issue of CF 1.0 vs CF 1.6 should not affect the actually data or really much at all.

But if you must resolve the issue with the dataset you are working with reach out to:
:contact = "oisst-help, email:" ;


Ed Armstrong
PO.DAAC Data Engineer

Re: Daily-OSST new convention issues

PostPosted: Tue Jan 05, 2021 8:07 am
by thomascap
Thanks Ed for your reply,

I already sent an email to this help desk address "" in addition to emailing and
Unfortunately I didn't get any answer for now.

I will continue to try to fix that problem.
Thanks again for your help.