401 Unauthorized on reanalysis-era5-pressure-levels since ~Aug 11, 2026 (single-levels unaffected)

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1

Hello,

Since ~11 August 2026, every request to reanalysis-era5-pressure-levels fails with:

401 Client Error: Unauthorized
Authentication failed
operation not allowed

Notes:

  • The same API key works fine for reanalysis-era5-single-levels at the same time.
  • Fails even on a minimal request (1 variable, 1 level, 1 hour, small bbox) — not a
    size/queue issue.
  • Re-generating the API key did not help.
  • The dataset’s own web download form also shows “We are experiencing problems,
    please try later” when loading the Variable panel.

Minimal reproduction:

import cdsapi
c = cdsapi.Client()
c.retrieve('reanalysis-era5-pressure-levels', {
    'product_type': 'reanalysis',
    'variable': ['temperature'],
    'pressure_level': ['500'],
    'year': '2025', 'month': '01', 'day': ['01'],
    'time': ['00:00'],
    'area': [43, 25, 35, 45],
    'format': 'netcdf',
}, 'test.nc')

Anyone else seeing this on reanalysis-era5-pressure-levels? Not sure if related to
the new “ERA5 time-series data on pressure levels” dataset published 7 Aug.

Thanks!

2

Hi,
I just tried to download the data from the form and it is working.
Could you please try again now?

Thanks