Implementation of IFS cycle 47r3

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 11 October 2021.

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:

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

Assimilation

• 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

Observations

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

Emissions

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

Other model changes

• Updated aerosol dry deposition based on Zhang & He (2014)
• Updated aerosol wet deposition based on Luo et al. (2019)

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 will be made available closer to the implementation date, documenting all the changes and their impact on the forecasts. 

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:

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

Software

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.

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