Description of upgrade

The CAMS IFS cycle 47R3 is based on ECMWF's  IFS cycle 47R3 . This is a minor upgrade with a limited set of scientific contributions.

The page will be updated as required. It was last changed on 23 February 2022.

For a record of changes made to this page please refer to Document versions .

Further information and advice regarding the upgrade can be obtained from the Copernicus User Support.

Timetable for implementation

The planned timetable for the implementation of the cycle 47r3 is as follows:

TBCAnnouncement of expected implementation date
12 Oct 2021


22 Feb 2022A fix of low-level T/q in fog conditions was introduced with the 12 UTC cycle on 22 Feb 2022.

The timetable represents current expectations and may change in light of actual progress made.

Current Status

IFS cycle 47r3 is going through its final preparation phase.

Meteorological content of the new cycle

The meteorological changes can be found on the ECMWF  IFS CY47R3 page.

Atmospheric composition content of the new cycle


  • Introduction of linear chemistry for NOx in minimization (tangent linear and adjoint code)
  • Updated background error statistics based on a more recent version of the model


  • Assimilation of Sentinel-5p NO2
  • Monitoring of VIIRS AOD
  • Monitoring of Sentinel-3/SLSTR AOD


  • Spatial smoothing applied to NO emission field in a limited area of Central Asia to eliminate numerical artefacts

Other model changes

Impact of the new cycle

For most compounds, the quality of the e-suite is very comparable to the o-suite. A substantial decrease in sulphate aerosol optical depth and an increase in sea salt aerosol optical depth are observed in the e-suite compared to the o-suite, and biases in aerosol properties (optical depth and size distribution) have improved. The impact of the assimilation of NO2 seems to be rather modest, and the performance of e-suite and o-suite is therefore similar. For CO the NDACC comparisons indicate increased negative biases and decreased correlations for high latitudes in the Northern Hemisphere, while other observations show little change. There are some indications that the upgrade of moist physics and related changes in convection influence the tracer distributions (e.g., CO profiles).
In summary, two improvements and a small degradation are reported for the e-suite compared to the o-suite. No major degradation was observed for any specific species or region. The scorecard below summarises the results. A comprehensive 
evaluation report of the 47r3 e-suite, documenting all the changes and their impact on the forecasts, is available from the CAMS website

Technical details of the new cycle

New and discontinued parameters

There are no new or discontinued parameters in the disseminated data compared to 47r2.

Change to GRIB encoding

As for the IFS Cycye 47r3 upgrade, the Master Tables Version Number for all parameters in GRIB 2 will be changed as follows:

Section 1
ecCodes key Master Tables Version Number
 10 tablesVersion5


28 from March 2022

All users are encouraged to check their data processing with the test data provided.


To handle the full range of parameters from this cycle, in particular the changed parameter names listed in the table below, ecCodes version 2.22.1 is required as a minimum. In fact, for the decoding of all data generated by IFS Cycle 47r3, ecCodes 2.23.0 or later is recommended.

paramIdold namenew name
210203GEMS OzoneOzone mass mixing ratio (full chemistry scheme)
211203GEMS OzoneOzone mass mixing ratio difference (full chemistry scheme)
210123Carbon monoxideCarbon monoxide mass mixing ratio
211123Carbon monoxideCarbon monoxide mass mixing ratio difference 
210121Nitrogen dioxideNitrogen dioxide mass mixing ratio
211121Nitrogen dioxideNitrogen dioxide mass mixing ratio difference 
210122Sulphur dioxideSulphur dioxide mass mixing ratio
211122Sulphur dioxideSulphur dioxide mass mixing ratio difference 
217019AmmoniaAmmonia mass mixing ratio
217027Nitrogen monoxideNitrogen monoxide mass mixing ratio

Availability of test data from the cycle 47r3 test suites

The CAMS operational FTP server (ECPDS) currently serves the most recent 3 days of test data in the directories "/DATA/CAMS_GLOBAL_TEST" and "/DATA/CAMS_EUROPE_BC_TEST" for global and regional boundary condition data, respectively. In addition, surface level fields (model level 137) are provided as individual files in the CAMS_GLOBAL_ADDITIONAL_TEST directory. Users wanting to access the output from the current test system for a longer period can access the data from 2 March 2021 onwards directly on MARS or through our WebAPI. More details can be found here: Accessing CAMS 47r3 test data.

Document versions

DateReason for update
1 July 2021

Initial version

9 July 2021ecCodes version requirement noted
20 August 2021Access to test data
2 September 2021Implementation date postpone by 1 week to 12 October 2021
4 October 2021Recommendation to use ecCodes version 2.23.0 with cycle 47r3 and highlight of a change in the GRIB 2 encoding
11 October 2021Main conclusions from external evaluation of the upgrade
23 FebruaryImplementation of a fix of low-level T/q in fog conditions