CDSAPI: reanalysis single-level is being download as a .zip when asked for "unarchived"

Software and Tools API
1

Hi there,

I’m trying to download data using python cdsapi using the following query:

{'product_type': ['reanalysis'], 'variable': ['top_net_thermal_radiation'], 'year': ['2024'], 'month': ['10'], 'day': ['31'], 'time': ['00:00', '01:00', '02:00', '03:00', '04:00', '05:00', '06:00', '07:00', '08:00', '09:00', '10:00', '11:00', '12:00', '13:00', '14:00', '15:00', '16:00', '17:00', '18:00', '19:00', '20:00', '21:00', '22:00', '23:00'], 'data_format': 'netcdf', **'download_format': 'unarchived'**}

While I explicitely require the unarchived netcdf data, the output is still downloaded as a zip archive. The archive contains two files that are:
data_stream-oper_stepType-accum.nc
data_stream-oper_stepType-instant.nc

I don’t understand what these “accum/instant” files are supposed to be

1 Like
2

This is happening to me too.

3

This is an announcement regarding the changes. I hope this will be helpful to you.

4

Thank you.

In summary, the GRIB->netcdf converter now returns instantaneous and accumulated variables.

5

Hello,
So what changes should I make to my code to be able to get the data in netcdf format as in my code currently I use that NetCDF data from ERA5 to be converted to an excel sheet and I am getting unknown format error when my code try to process the .nc file downloaded from CDS

6

Hi Yuyang,

Thanks for the explanation. However, it is still not clear to me what are the meaning of the “accumulated” and “instantaneous” variables. Different variables are stored in these two files. What are the definitions of the accumulated and instant variables?

7

Hi,
please have a look here: ERA5 terminology: analysis and forecast; time and steps; instantaneous and accumulated and mean rates and min/max parameters - Copernicus Knowledge Base - ECMWF Confluence Wiki

Thanks