DRAFT
Description of upgrade
The CAMS IFS cycle 49R1 is based on ECMWF's IFS Cycle 49r1. This is an upgrade with a limited number of scientific contributions for the atmospheric composition aspects. Key elements are an update of the global emissions to the CAMS-GLOB-ANT 6.1 dataset and improvements to the modelling of aerosol. More information can be found below.
The page will be updated as required. It was last changed on 13 September 2024.
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 our User Support.
Timetable for implementation
The planned timetable for the implementation of the cycle 49r1 is as follows:
| Date | Event |
|---|---|
| September 2024 | Announcement of expected implementation date |
| 12 November 2024 | Implementation |
The timetable represents current expectations and may change in light of actual progress made
Current Status
IFS cycle 49r1 is going through its final preparation phase.
Meteorological content of the new cycle
The meteorological changes can be found on the ECMWF IFS CY49R1 page.
Atmospheric composition content of the new cycle
Assimilation
- No updates
Observations
- No updates
Emissions
- CAMS-GLOB-ANT 5.3 (based on EDGAR 5, used in 48r1) has been replaced by CAMS-GLOB_ANT 6.1 (based on EDGAR 6 and 7)
Model changes
- Improvements to the aerosol removal processes (wet deposition) and aerosol ageing in the atmosphere
- Modelling of the formation of (secondary) aerosol from precursor gases with more detail (EQSAM4Clim module has been activated)
Impact of the new cycle
A comprehensive evaluation report of the 49r1 e-suite, documenting all the changes and their impact on the forecasts will be provided ahead of the actual implementation. Initial testing results show improved aerosol forecasts.
Technical details of the new cycle
New and discontinued parameters
Several of the upgrades in CY49R1 have resulted in new parameters, some of which will be added to the dissemination through the Atmosphere Data Store (ADS) and the ECPDS ftp server. For now, the main new parameters are listed in the table below. Others might be added based on user requests. (any changes?)
Change to GRIB encoding
The GRIB model identifiers (generating process identification number) for cycle 49r1 will be changed as follows:
GRIB 1 Section 1 Octets | GRIB 2 Section 4 Octets | ecCodes key | Component | Model identifier | |
|---|---|---|---|---|---|
48r1 | 49r1 | ||||
6 | 14 | generatingProcessIdentifier | Atmospheric model | 154 | 158 |
6 | 14 | generatingProcessIdentifier | Ocean wave model | 119 | 106 |
For all parameters in GRIB 2 the Master Tables Version Number will be changed as follows:
GRIB 2 Section 1 Octets | ecCodes key | Master Tables Version Number | |
|---|---|---|---|
48r1 | 49r1 | ||
10 | tablesVersion | 30 | 32 |
Software
To handle the data of Cycle 49r1 we recommend to use the ECMWF software packages
ecCodes 2.36.0 (minimum version 2.35.1)
CodesUI 1.8.0 (minimum version 1.7.3)
Magics 4.15.4 (minimum version 4.13.0)
Metview 5.22.1
ODC 1.5.2 (minimum version 1.4.6)
On the ATOS HPC these versions correspond to ecmwf-toolbox/2024.06.0.0.
Availability of test data from the cycle 49r1 test suites
Document versions
| Date | Reason for update |
|---|---|
| 13 September 2024 | Initial version |