Description of upgrade
The CAMS IFS cycle 46R1 is based on ECMWF's IFS cycle 46R1 . IFS Cycle 46r1 is an upgrade with many scientific contributions, including changes in the use of observations and in modelling. The new cycle also includes an upgrade of the vertical resolution from 60 model levels to 137 model levels.
The page will be updated as required. It was last changed on 11.04.2019.
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 User Support.
Timetable for implementation
The planned timetable for the implementation of the cycle 46r1 is as follows:
| Date | Event |
|---|---|
| TBC | Announcement of expected implementation date |
| TBC | Implementation |
The timetable represents current expectations and may change in light of actual progress made.
Current Status
IFS cycle 46r1 is going through its final testing phase.
Meteorological content of the new cycle
The meteorological changes can be found on the ECMWF IFS CY46R1 page .
Atmospheric composition content of the new cycle
Assimilation
- New model-error covariance matrices for aerosol and chemistry at 137 levels.
Observations
- TBC
Model
- Updated to use new CAMS_GLOB emissions inventory.
- Diurnal cycle for biomass-burning emissions updated to match that assumed within GFAS.
- Diurnal cycle for SOA production introduced to reduce night-time overestimation.
- New online dust emission scheme (Nabat et al., 2012).
- Sea-salt production over freshwater lakes eliminated.
- New nitrate and ammonium aerosol species, coupled to the gas-phase nitrogen chemistry. See new model parameters below
Sulfur species (SO2 and SO4) coupled between chemistry and aerosol schemes. See discontinued parameters below.
- Online calculation of dry deposition velocities for trace gases. (This was already in place for aerosols in 45r1.)
- Updates to wet deposition parameterisations. This brings greater distinction between scavenging by liquid and ice, and harmonises the treatment for aerosols and trace gases.
- Updates to chemical reaction rates.
- Updated to use new CAMS_GLOB emissions inventory.
Impact of the new cycle
The new cycle is being validated by the CAMS Validation team and the results will be presented in a validation report.
Technical details of the new cycle
Changes to GRIB encoding
Model identifiers
The GRIB model identifiers (generating process identification number) for cycle 46R1 will be changed as follows:
| GRIB 1 Section 1 Octets | GRIB 2 Section 4 Octets | grib_api key | Component | Model ID | |
|---|---|---|---|---|---|
| Old | New | ||||
| 6 | 14 | generatingProcessIdentifier | Atmospheric model | 149 | 150 |
| Ocean wave model | 114 | 115 | |||
| HRES stand-alone ocean wave model | 214 | 215 | |||
New model output parameters
| paramId | shortName | name | units | GRIB edition | Components | Test data available | Dissemination | ecCharts | Added to the Catalogue |
|---|---|---|---|---|---|---|---|---|---|
Model levels | |||||||||
| 210247 | aermr16 | Nitrate fine mode aerosol mass mixing ratio | kg kg-1 | 2 | CAMS aerosol model | TBC | TBC | TBC | TBC |
| 210248 | aermr17 | Nitrate coarse mode aerosol mass mixing ratio | kg kg-1 | 2 | CAMS aerosol model | TBC | TBC | TBC | TBC |
| 210249 | aermr18 | Ammonium aerosol mass mixing ratio | kg kg-1 | 2 | CAMS aerosol model | TBC | TBC | TBC | TBC |
| Pressure levels | |||||||||
| 210247 | aermr16 | Nitrate fine mode aerosol mass mixing ratio | kg kg-1 | 1 | CAMS aerosol model | TBC | TBC | TBC | TBC |
| 210248 | aermr17 | Nitrate coarse mode aerosol mass mixing ratio | kg kg-1 | 1 | CAMS aerosol model | TBC | TBC | TBC | TBC |
| 210249 | aermr18 | Ammonium aerosol mass mixing ratio | kg kg-1 | 1 | CAMS aerosol model | TBC | TBC | TBC | TBC |
Surface level | |||||||||
| 210250 | niaod550 | Nitrate aerosol optical depth at 550 nm | dimensionless | 1 | CAMS aerosol model | TBC | TBC | TBC | TBC |
| 210251 | amaod550 | Ammonium aerosol optical depth at 550 nm | dimensionless | 1 | CAMS aerosol model | TBC | TBC | TBC | TBC |
Discontinued model parameters
The "SO2 aerosol precursor" (aermr12/210012 and related diagnostics 215168–215175) have been discontinued, as the aerosol scheme now uses the same SO2 tracer as the chemistry (so2/210122).
Similarly, the sulfate tracer in the chemistry scheme (so4/217020 and related diagnostic tcso4/218020) is no longer used, as the chemistry now uses the same sulfate tracer as the aerosol (aermr11/210011).
Software
ecCodes
ecCodes version 2.12.1 provides full support for the new CAMS model output parameters introduced in IFS Cycle 46r1.
Availability of test data from the cycle 46r1 test suites
Test data is available from MARS, either through direct access or through WebAPI. The CAMS operational FTP server (ECPDS) also serves daily test data in the directory "/DATA/CAMS_GLOBAL_TEST" and "/DATA/CAMS_EUROPE_BC_TEST" for global and regional boundary condition data, respectively. More details can be found here .
Document versions
| Date | Reason for update |
|---|---|
| 11.04.2019 |
|