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The page will be updated as required. It was last changed on 25 April 12 June 2023.
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 our User Support.
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| Table of Contents | ||||
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The planned timetable for the implementation of the cycle 47r3 48r1 is as follows:
| Date | Event |
|---|---|
| March 2023 | Announcement of expected implementation date |
| 27 June 2023 | Implementation |
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A comprehensive evaluation report of the 48r1 e-suite, documenting all the changes and their impact on the forecasts, is in preparation and will be provided before the implementation date. Based on the evaluation of the testing of all individual changes and the preliminary evaluation of the final e-suite, the following aspects for key species should be noted:
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has now been provided and can be found here: Upgrade Verification Note. It summarizes the impact as follows: The aerosol optical depth evaluation shows improvements for most regions. The Angstrom exponent, which is a measure representative of the aerosol size distribution, shows some improvement on the global scale but over the Sahara the performance deteriorates showing a too large fraction of coarse particles. Particulate matter (PM10 and PM2.5) at the surface is reduced in e-suite, which led to worse performance in East Asia and similar performance over North America and Europe. Surface ozone and tropospheric ozone shows similar performance. Stratospheric ozone and total column ozone have improved against observations, especially in the Tropics. The performance for CO has generally improved against all observations, except MOPITT. NO2 and SO2 both show improved validation results against multiple observations. The overestimation of HCHO in the Tropics is more pronounced in the e-suite compare to TROPOMI. Finally, the UV evaluation shows only minor changes.
Scorecard for the relative performance of the e-suite versus the performance of the o-suite against observations. Meaning of the “relative score” symbols: (++) e-suite performs significantly better than the o-suite (+) e-suite shows small improvements, (n) (neutral) no significant difference between o-suite and e-suite, (-) score is somewhat degraded in the e-suite, (–) e-suite performs significantly worse than the o-suite. Remote: Remote Sensing from surface station, AOD: Aerosol Optical Depth at 550nm, Angstrom exponent between 440nm and 870nm, PM10: Particulate matter less than 10 microns, PM2.5: Particulate matter less than 2.5 microns
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Technical details of the new cycle
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| paramId | shortName | name | units | GRIB edition | Components | Test data available |
|---|---|---|---|---|---|---|
Model levels | ||||||
| 210252 | aermr19 | Biogenic secondary organic aerosol mass mixing ratio | kg kg-1 | 2 | CAMS aerosol model | yes |
| 210253 | aermr20 | Anthropogenic secondary organic aerosol mass mixing ratio | kg kg-1 | 2 | CAMS aerosol model | yes |
| glyoxal | Glyoxal | kg kg-1 | 2 | CAMS chemistry model | yes | |
| Pressure levels | ||||||
| 210252 | aermr19 | Biogenic secondary organic aerosol mass mixing ratio | kg kg-11 | 2 | CAMS aerosol model | yes |
| 210253 | aermr20 | Anthropogenic secondary organic aerosol mass mixing ratio | kg kg-11 | 2 | CAMS aerosol model | yes |
| 217107 | glyoxal | Glyoxal | kg kg-11 | 2 | CAMS chemistry model | yes |
Surface level | ||||||
| 215226 | soaod550 | Secondary organic aerosol optical depth at 550 nm | dimensionless | 12 | CAMS aerosol model | yes |
| 218107 | tc_glyoxal | Total column of glyoxal | kg m-2 | 12 | CAMS chemistry model | yes |
Change to GRIB encoding
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GRIB 1 Section 1 Octets | GRIB 2 Section 4 Octets | ecCodes key | Model identifier | |
|---|---|---|---|---|
47r3 | 48r1 | |||
6 | 14 | generatingProcessIdentifier | 153 | 154 |
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 | |
|---|---|---|---|
| 47r3 | 48r1 | ||
| 10 | tablesVersion | 28 | 30 |
| Warning |
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| Warning |
While by default all 48r1 gridded GRIB2 data will be disseminated |
By default all gridded 48r1 direct model output in GRIB 2 will be encoded using a CCSDS defined compression method (Data representation template 5.42) and any , MARS will by default write gridded GRIB2 data in CCSDS only if derived from such fields will inherit the CCSDS compression. This affects e.g. fields produced on Gaussian grids, like specific humidity on model levels, or surface fields like most-unstable CAPE. See below on (gridded) CCSDS-packed GRIB2 fields. See below how to override the default behaviour. ecCodes, our encoding/decoding package, uses libaec (Adaptive Entropy Coding Library) which implements a Golomb-Rice coding as defined in the CCSDS recommended standard 121.0-B-3. Users are strongly advised to test that their software applications and data processing chain can handle this new compression method. To handle CCSDS compressed fields from 48r1 with ecCodes, version 2.2830.0 or newer is recommended. For a discussion of available GRIB packing methods and the use of compression algorithms see the Technical Memo Impact of GRIB compression on weather forecast data and data-handling applications. |
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GRIB 2 | ecCodes key | 47r3 | 48r1 |
|---|---|---|---|
10-11 | dataRepresentationTemplateNumber (GRIB2 only) | 0 (simple packing) | 42 (CCSDS compression) |
packingType (edition independent) | grid_simple | grid_ccsds |
Default packing types for data from Dissemination and MARS
With 48r1 all gridded GRIB2 "raw" data will use With the introduction of the new CCSDS packing type the . The default behaviour in for data from dissemination and MARS (from 14 March) 00 UTC run 21/3/2023) and MARS will be as follows:
| Input field | ||
|---|---|---|
| MARS output packing type (with keyword grid=... ) | Dissemination output | |
| packing type (with keyword grid=... ) | ||
| GRIB1/GRIB2 gridded | inherited from input | GRIB1/inherited from input |
| GRIB1 SH | simple | simple |
| GRIB2 SH | simple | CCSDS |
While by default all 48r1 gridded GRIB2 data will be disseminated in CCSDS packing, MARS will This implies that by default only fields write gridded GRIB2 data in CCSDS if derived from (gridded) CCSDS-packed GRIB2 fields.
from 48r1 onwards will use packing type CCSDS. The default behaviour can be overridden by specifying the packing explicitly, e.g.
grid = 0.1/0.1,
packing = CCSDS
will deliver fields with CCSDS packing for any GRIB2 input field. It will however not be possible to get CCSDS packed fields from GRIB1 input fields. Similarly, if CCSDS compression is not desired when retrieving gridded GRIB 2 fields from MARS or dissemination, simple packing can be requested with keyword
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Using ecCodes, already retrieved CCSDS compressed fields can be converted to other packing types. This is how to convert all messages in file ccsds.grib with grid_ccsds as their packingType, and only those, to use simple packing, i.e. what we used before 48r1:
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| Note | ||
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The CAMS operational FTP server (ECPDS) will serve the most recent 3 days of test data, once the e-suite is running in near-real-time, 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) will be provided as individual files in the "/DATA/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 1 September 2022 onwards directly on MARS or through the Atmosphere Data Store. More details can be found here: Accessing CAMS 48r1 test data. |
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| Date | Reason for update |
|---|---|
| 16 February 2023 | Initial version |
| 29 March 2023 | Detailed list of changes and expected implementation date |
| 19 April 2023 | Added table with new parameters |
| 25 April | Update of Impact section |
| 05 May 2023 | Update of Change to GRIB encoding section and Default packing types section |
| 12 June 2023 | Addition of evaluation report |