A bug in cdsapi ERA5 Table 12 download

Software and Tools API
,
1

I found a bug in downloading ERA5 Table 12 data. When downloading parameter list including paramIds 129 (geopotential) and 152 (log of surf pressure), all other parameters are ignored. If I omit 129 and 152 from the parameter list, every other parameter is downloaded correctly.

In a previous version (summer 2024) this bug did not exist, so my guess is this is due to how cdsapi interpretes requests, not in the database itself(?)

Here is my code (bug_ERA5_T12.py)

# Highlight bug in ERA5 Table 12 model layer download
# https://confluence.ecmwf.int/display/CKB/ERA5%3A+data+documentation#ERA5:datadocumentation-Table12

import cdsapi
from netCDF4 import Dataset

def debug_A(fn):
    c = cdsapi.Client()
    r = c.retrieve('reanalysis-era5-complete', {
        'class'         : 'ea',
        'date'          : '2024-06-11/to/2024-06-15',
        'levelist'      : '1/100/116/132/133/134/135/136/137',
        'levtype'       : 'ml',
        'param'         : '129/130/131/132/133/152/246/247/248',
        'stream'        : 'oper',
        'time'          : '12:00:00/16:00:00',
        'type'          : 'an',
        'area'          : '24.75/14.75/25.25/15.25',
        'grid'          : ['0.25', '0.25'],
        'format'        : 'netcdf',
        'data_format'   : 'netcdf'
    })
    r.download(fn)

def debug_B(fn):
    c = cdsapi.Client()
    r = c.retrieve('reanalysis-era5-complete', {
        'class'         : 'ea',
        'date'          : '2024-06-11/to/2024-06-15',
        'levelist'      : '1/100/116/132/133/134/135/136/137',
        'levtype'       : 'ml',
        # 'param'         : '129/130/131/132/133/152/246/247/248',
        'param'         : '130/131/132/133/246/247/248',  # without 129 and 152
        'stream'        : 'oper',
        'time'          : '12:00:00/16:00:00',
        'type'          : 'an',
        'area'          : '24.75/14.75/25.25/15.25',
        'grid'          : ['0.25', '0.25'],
        'format'        : 'netcdf',
        'data_format'   : 'netcdf'
    })
    r.download(fn)

def read_varlist(fn):
    ncfile = Dataset(fn, 'r')
    keywords = ncfile.variables.keys()
    print('%s contains variables: ' % fn)
    print(*keywords, sep=', ')
    ncfile.close()

def read_one_var(fn, var):
    ncfile = Dataset(fn, 'r')
    lev = ncfile.variables[var]
    print('%s variable:' % fn)
    print(lev)
    print('With values:')
    print(*lev)
    ncfile.close()

And here is an interactive run:
(Outputs indented)

import bug_ERA5_T12
bug_ERA5_T12.debug_A('A_result.nc')
bug_ERA5_T12.debug_B('B_result.nc')
bug_ERA5_T12.read_varlist('A_result.nc')
    A_result.nc contains variables: 
    valid_time, model_level, latitude, longitude, expver, z, lnsp
bug_ERA5_T12.read_one_var('A_result.nc','model_level')
    A_result.nc variable:
    <class 'netCDF4.Variable'>
    float64 model_level(model_level)
        _FillValue: nan
        long_name: hybrid level
        units: 1
        positive: down
        standard_name: atmosphere_hybrid_sigma_pressure_coordinate
    unlimited dimensions: 
    current shape = (1,)
    filling on
    With values:
    1.0
bug_ERA5_T12.read_varlist('B_result.nc')
    B_result.nc contains variables: 
    valid_time, model_level, latitude, longitude, expver, t, q, clwc, ciwc, cc, u, v
bug_ERA5_T12.read_one_var('B_result.nc','model_level')
    B_result.nc variable:
    <class 'netCDF4.Variable'>
    float64 model_level(model_level)
        _FillValue: nan
        long_name: hybrid level
        units: 1
        positive: down
        standard_name: atmosphere_hybrid_sigma_pressure_coordinate
    unlimited dimensions: 
    current shape = (9,)
    filling on
    With values:
    1.0 100.0 116.0 132.0 133.0 134.0 135.0 136.0 137.0
2

Hi,
this is related to this change: Forthcoming update to the format of netCDF files produced by the conversion of GRIB data on the CDS
You need to ask for 129 and 152 separately.

Thanks

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