From c9197fe21b8e830d8a018c4d3285855d3c35e11c Mon Sep 17 00:00:00 2001 From: Robert Osinski Date: Thu, 5 Feb 2026 14:51:45 +0000 Subject: [PATCH 01/10] ADR-001 for CEMS / C3S hydrology --- MARS language/ADR-001-CEMS-C3S-Hydrology.md | 50 ++++++++++++++++++ MARS language/ADR-Template.md | 58 +++++++++++++++++++++ 2 files changed, 108 insertions(+) create mode 100644 MARS language/ADR-001-CEMS-C3S-Hydrology.md create mode 100644 MARS language/ADR-Template.md diff --git a/MARS language/ADR-001-CEMS-C3S-Hydrology.md b/MARS language/ADR-001-CEMS-C3S-Hydrology.md new file mode 100644 index 0000000..38a2560 --- /dev/null +++ b/MARS language/ADR-001-CEMS-C3S-Hydrology.md @@ -0,0 +1,50 @@ +# Architectural Decision Record XXX: Title of the Decision + +## Status +[**Proposed** | Accepted | Deprecated | Superseded by [ADR-XXX]] + +## Last Updated +2025-15-16 + +## Context + +For CEMS and C3S, hydrological data are produced with different hydrological models which are driven by different atmospheric model and observational data. +The layout of the current way hydrological data is archived will change. In CEMS, the different hydrological versions for the European and the global domain go into different streams under class ce. The new layout has four distinct classes for the European CEMS / C3S and the global counterparts. +The hydrological model in the current layout is stored in the ‘model’ keyword. This proposed layout will also use the model keyword for the hydrological model. One problem with the existing layout is that different model configurations used for producing the climatologies were referenced through the keyword date, which caused overwriting issues with the reforecast data. Therefore, the proposal includes introducing a new MARS keyword, configuration, which specifies not only the model version but also additional information about the setup. +Examples of different configurations used in CEMS and C3S are: +* v1, v4 +* v1-c3s-e_catchment +* v1-c3s-e_grid +* v1-c3s-ww + +The forcing is in the old layout specified by the origin mars keyword, e.g., origin=ecmf/edwz/cosmo. +As for ECMWF forcings will include IFS as well as AIFS. origin=ecmf is no longer sufficient to distinguish between the two models. With the specific post-processing templates, we are using in GRIB2 to encode the data, it is possible to distinguish the data and a string can be created for ecmf_ifs and ecmf_aifs, In general, this follows the format "centre_model", which provides more information than the current origin key. +For this reason, we propose introducing a new MARS keyword called ‘forcing’, which would more accurately represent the model used to produce the data. + + +### Options Considered + +We propose two new mars keywords. The configuration keyword keeps the information about the model version and the setup running. +The 2nd proposed key is the forcing keyword which contains the centre identifier together with the modelName. This is needed to distinguish AIFS and IFS for ECMWF, but also Cosmo and ICON. + + +### Analysis + +We did not consider other options than option 1. + +## Decision + + + +### Related Decisions + +## Consequences + + +## References + +## Authors +- Sebastien Villaume +- Robert Osinski +- Mohamed Azhar + diff --git a/MARS language/ADR-Template.md b/MARS language/ADR-Template.md new file mode 100644 index 0000000..9a77c77 --- /dev/null +++ b/MARS language/ADR-Template.md @@ -0,0 +1,58 @@ +# Architectural Decision Record XXX: Title of the Decision + +## Status +[**Proposed** | Accepted | Deprecated | Superseded by [ADR-XXX]] + +## Last Updated +YYYY-MM-DD + +## Context + +[ ] Explained the business or technical problem being solved +[ ] Described relevant constraints (time, budget, technology, regulatory) +[ ] Provided sufficient background for someone unfamiliar with the project +[ ] Included relevant ECMWF-specific considerations (operational requirements, data volumes, performance needs, etc) + +### Options Considered + +[ ] Listed all seriously considered alternatives +[ ] Provided brief descriptions of each option +[ ] Included pros and cons for each alternative + +### Analysis + +[ ] Compared options against relevant criteria (cost, performance, maintainability, risk, etc) +[ ] Explained trade-offs and their implications +[ ] Referenced any prototypes, benchmarks, or research conducted (if applicable) +[ ] Considered both immediate and long-term impacts + +## Decision + +[ ] Stated the chosen option (clearly and unambiguously) +[ ] Avoided implementation details (unless crucial to understanding the decision) +[ ] Included any conditions or limitations on the decision + +### Related Decisions + +[ ] Referenced other ADRs that influenced or are influenced by this decision +[ ] Noted any decisions this ADR modifies or supersedes +[ ] Considered impacts on existing architectural patterns +[ ] Referenced ECMWF previous decisions that may be relevant but not documented as ADRs + +## Consequences + +[ ] Listed both positive and negative expected outcomes (if applicable) +[ ] Included impacts on performance, maintainability, team productivity, operations, etc +[ ] Noted any new risks introduced or mitigated +[ ] Considered implications for future decisions + +## References + +[ ] Linked to any relevant documents, discussions, or resources that informed the decision +[ ] Included links to related ADRs, design documents, or external references + +## Authors + +- Author 1 +- Author 2 +- Author 3 \ No newline at end of file From 8a583d31caffc54b0459d704495725a8fc2e05c7 Mon Sep 17 00:00:00 2001 From: Robert Osinski Date: Thu, 5 Feb 2026 14:55:58 +0000 Subject: [PATCH 02/10] add missing title --- MARS language/ADR-001-CEMS-C3S-Hydrology.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/MARS language/ADR-001-CEMS-C3S-Hydrology.md b/MARS language/ADR-001-CEMS-C3S-Hydrology.md index 38a2560..2a05301 100644 --- a/MARS language/ADR-001-CEMS-C3S-Hydrology.md +++ b/MARS language/ADR-001-CEMS-C3S-Hydrology.md @@ -1,4 +1,4 @@ -# Architectural Decision Record XXX: Title of the Decision +# Architectural Decision Record 001: CEMS and C3S hydrology data in MARS ## Status [**Proposed** | Accepted | Deprecated | Superseded by [ADR-XXX]] From b408bf960b11819a6e82cb23146bf815a97d68d3 Mon Sep 17 00:00:00 2001 From: Robert Osinski Date: Tue, 19 May 2026 13:47:59 +0000 Subject: [PATCH 03/10] rename ADR MARS hydrology document --- MARS language/ADR-Template.md | 58 ------------------- ...logy.md => MARS-005-CEMS-C3S-Hydrology.md} | 0 2 files changed, 58 deletions(-) delete mode 100644 MARS language/ADR-Template.md rename MARS language/{ADR-001-CEMS-C3S-Hydrology.md => MARS-005-CEMS-C3S-Hydrology.md} (100%) diff --git a/MARS language/ADR-Template.md b/MARS language/ADR-Template.md deleted file mode 100644 index 9a77c77..0000000 --- a/MARS language/ADR-Template.md +++ /dev/null @@ -1,58 +0,0 @@ -# Architectural Decision Record XXX: Title of the Decision - -## Status -[**Proposed** | Accepted | Deprecated | Superseded by [ADR-XXX]] - -## Last Updated -YYYY-MM-DD - -## Context - -[ ] Explained the business or technical problem being solved -[ ] Described relevant constraints (time, budget, technology, regulatory) -[ ] Provided sufficient background for someone unfamiliar with the project -[ ] Included relevant ECMWF-specific considerations (operational requirements, data volumes, performance needs, etc) - -### Options Considered - -[ ] Listed all seriously considered alternatives -[ ] Provided brief descriptions of each option -[ ] Included pros and cons for each alternative - -### Analysis - -[ ] Compared options against relevant criteria (cost, performance, maintainability, risk, etc) -[ ] Explained trade-offs and their implications -[ ] Referenced any prototypes, benchmarks, or research conducted (if applicable) -[ ] Considered both immediate and long-term impacts - -## Decision - -[ ] Stated the chosen option (clearly and unambiguously) -[ ] Avoided implementation details (unless crucial to understanding the decision) -[ ] Included any conditions or limitations on the decision - -### Related Decisions - -[ ] Referenced other ADRs that influenced or are influenced by this decision -[ ] Noted any decisions this ADR modifies or supersedes -[ ] Considered impacts on existing architectural patterns -[ ] Referenced ECMWF previous decisions that may be relevant but not documented as ADRs - -## Consequences - -[ ] Listed both positive and negative expected outcomes (if applicable) -[ ] Included impacts on performance, maintainability, team productivity, operations, etc -[ ] Noted any new risks introduced or mitigated -[ ] Considered implications for future decisions - -## References - -[ ] Linked to any relevant documents, discussions, or resources that informed the decision -[ ] Included links to related ADRs, design documents, or external references - -## Authors - -- Author 1 -- Author 2 -- Author 3 \ No newline at end of file diff --git a/MARS language/ADR-001-CEMS-C3S-Hydrology.md b/MARS language/MARS-005-CEMS-C3S-Hydrology.md similarity index 100% rename from MARS language/ADR-001-CEMS-C3S-Hydrology.md rename to MARS language/MARS-005-CEMS-C3S-Hydrology.md From e36f26beff309386a79a32356f78d43f9b7122ee Mon Sep 17 00:00:00 2001 From: Robert Osinski Date: Tue, 19 May 2026 13:54:01 +0000 Subject: [PATCH 04/10] adapt title --- MARS language/MARS-005-CEMS-C3S-Hydrology.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/MARS language/MARS-005-CEMS-C3S-Hydrology.md b/MARS language/MARS-005-CEMS-C3S-Hydrology.md index 2a05301..d0867d2 100644 --- a/MARS language/MARS-005-CEMS-C3S-Hydrology.md +++ b/MARS language/MARS-005-CEMS-C3S-Hydrology.md @@ -1,4 +1,4 @@ -# Architectural Decision Record 001: CEMS and C3S hydrology data in MARS +# MARS Language Decision Record 005: CEMS and C3S hydrology data in MARS ## Status [**Proposed** | Accepted | Deprecated | Superseded by [ADR-XXX]] From d16a9f5b76b8749c8ed166f40def70f092faf630 Mon Sep 17 00:00:00 2001 From: Robert Osinski Date: Tue, 19 May 2026 15:00:11 +0000 Subject: [PATCH 05/10] decision part --- MARS language/MARS-005-CEMS-C3S-Hydrology.md | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/MARS language/MARS-005-CEMS-C3S-Hydrology.md b/MARS language/MARS-005-CEMS-C3S-Hydrology.md index d0867d2..98781c8 100644 --- a/MARS language/MARS-005-CEMS-C3S-Hydrology.md +++ b/MARS language/MARS-005-CEMS-C3S-Hydrology.md @@ -1,10 +1,10 @@ # MARS Language Decision Record 005: CEMS and C3S hydrology data in MARS ## Status -[**Proposed** | Accepted | Deprecated | Superseded by [ADR-XXX]] +[~~Proposed~~ | **Accepted** | ~~Deprecated~~ | ~~Superseded by [ADR-XXX]~~] ## Last Updated -2025-15-16 +2025-05-19 ## Context @@ -33,7 +33,12 @@ The 2nd proposed key is the forcing keyword which contains the centre identifier We did not consider other options than option 1. ## Decision - +| mars_abbreviation | long_name | +|:-----------------:|:---------------------------------------| +| ef | EFAS (European flood awareness system) | +| gf | GLOFAS (Global flood awareness system) | +| eh | C3S European hydrology | +| gh | C3S Global hydrology | ### Related Decisions From 71f7869dba5a662c3ca6a445b0c7e71656b0e13f Mon Sep 17 00:00:00 2001 From: Robert Osinski Date: Tue, 19 May 2026 15:10:44 +0000 Subject: [PATCH 06/10] finaling MARS ADR for hydrology --- MARS language/MARS-005-CEMS-C3S-Hydrology.md | 27 +++++++++++++++++++- 1 file changed, 26 insertions(+), 1 deletion(-) diff --git a/MARS language/MARS-005-CEMS-C3S-Hydrology.md b/MARS language/MARS-005-CEMS-C3S-Hydrology.md index 98781c8..b89b4bb 100644 --- a/MARS language/MARS-005-CEMS-C3S-Hydrology.md +++ b/MARS language/MARS-005-CEMS-C3S-Hydrology.md @@ -33,13 +33,38 @@ The 2nd proposed key is the forcing keyword which contains the centre identifier We did not consider other options than option 1. ## Decision -| mars_abbreviation | long_name | +The hydrology data will be archived under the following MARS classes: + +| MARS class | Name | |:-----------------:|:---------------------------------------| | ef | EFAS (European flood awareness system) | | gf | GLOFAS (Global flood awareness system) | | eh | C3S European hydrology | | gh | C3S Global hydrology | +A MARS key forcing will be introduced which will get values like +* ecmf-ifs +* ecmf-aifs +* ecmf-era5 +* ecmf-seas +* edzw-icon +* cosmo-cosmo +* cmcc-sps +* obs + +This is the centre abbreviation dash the modelName. A configuration key will be introduced as well but only used in stream rfsd. It will contain the following values: +* v1.0 +* v1.0-catchment +* v1.0-grid +* v1.0-c3s +* v2.0 +* v2.1 +* v3.0 +* v3.1 +* v3.5 +* v4.0 +* v5.0 + ### Related Decisions From f492b6767b12d6f4a18f68ce3e0bb2ad300c7895 Mon Sep 17 00:00:00 2001 From: Robert Osinski Date: Wed, 27 May 2026 13:09:53 +0000 Subject: [PATCH 07/10] some changes on the ADR hydrology text --- MARS language/MARS-005-CEMS-C3S-Hydrology.md | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/MARS language/MARS-005-CEMS-C3S-Hydrology.md b/MARS language/MARS-005-CEMS-C3S-Hydrology.md index b89b4bb..4b86ce5 100644 --- a/MARS language/MARS-005-CEMS-C3S-Hydrology.md +++ b/MARS language/MARS-005-CEMS-C3S-Hydrology.md @@ -8,24 +8,23 @@ ## Context -For CEMS and C3S, hydrological data are produced with different hydrological models which are driven by different atmospheric model and observational data. +CEMS and C3S hydrological data are produced with different hydrological models which are driven by different atmospheric model and observational data. The layout of the current way hydrological data is archived will change. In CEMS, the different hydrological versions for the European and the global domain go into different streams under class ce. The new layout has four distinct classes for the European CEMS / C3S and the global counterparts. -The hydrological model in the current layout is stored in the ‘model’ keyword. This proposed layout will also use the model keyword for the hydrological model. One problem with the existing layout is that different model configurations used for producing the climatologies were referenced through the keyword date, which caused overwriting issues with the reforecast data. Therefore, the proposal includes introducing a new MARS keyword, configuration, which specifies not only the model version but also additional information about the setup. +The hydrological model in the current layout is indexed using the ‘model’ keyword. This new proposed layout will also use the model keyword for indexing the hydrological model. One problem with the existing layout is that different model configurations used for producing the climatologies were referenced through the keyword date, which caused overwriting issues with the reforecast data. Therefore, the proposal includes introducing a new MARS keyword, configuration, which specifies not only the model version but also additional information about the setup. This configuration keyword is intended to be used only for the hindcasts as for all other data, there is no overlapping of different configurations at the same point in time. Examples of different configurations used in CEMS and C3S are: * v1, v4 * v1-c3s-e_catchment * v1-c3s-e_grid * v1-c3s-ww -The forcing is in the old layout specified by the origin mars keyword, e.g., origin=ecmf/edwz/cosmo. -As for ECMWF forcings will include IFS as well as AIFS. origin=ecmf is no longer sufficient to distinguish between the two models. With the specific post-processing templates, we are using in GRIB2 to encode the data, it is possible to distinguish the data and a string can be created for ecmf_ifs and ecmf_aifs, In general, this follows the format "centre_model", which provides more information than the current origin key. +The hydrological data are driven by different atmospheric data. In the old layout this was specified by the origin mars keyword, e.g., origin=ecmf/edwz/cosmo. As for ECMWF forcings will include IFS as well as AIFS, origin=ecmf is no longer sufficient to distinguish between the two models. With the specific post-processing templates, we are using in GRIB2 to encode the data, it is possible to distinguish the data and a string can be created like for example ecmf_ifs or ecmf_aifs. In general, this follows the format "centre_model", which provides more information than the current origin key. For this reason, we propose introducing a new MARS keyword called ‘forcing’, which would more accurately represent the model used to produce the data. ### Options Considered -We propose two new mars keywords. The configuration keyword keeps the information about the model version and the setup running. -The 2nd proposed key is the forcing keyword which contains the centre identifier together with the modelName. This is needed to distinguish AIFS and IFS for ECMWF, but also Cosmo and ICON. +We propose to introduce two new MARS keywords. +The configuration keyword stores information about the model version and the current running setup in a single key. The 2nd proposed key is the forcing keyword which contains the centre identifier together with the modelName to describe the data used to drive the hydrological model. This is needed to distinguish AIFS and IFS for ECMWF, but also the DWD Cosmo and ICON models which is not doable with the existing origin keyword. ### Analysis @@ -69,7 +68,8 @@ This is the centre abbreviation dash the modelName. A configuration key will be ### Related Decisions ## Consequences - +The data will be stored in newly created MARS classes, ensuring that existing datasets remain unaffected, except for the hydrology data, which will be rearchived within the new layout. +The forcing and configuration MARS keywords are also applicable in other contexts. For example, the fire datasets are based on ERA5 and IFS medium-range forecasts. The configuration keyword can likewise be applied to the land data assimilation system, which operates with different model versions running in parallel to support multiple target forecasting systems that rely on this data as input. ## References From 842ede381ccff268ea3be37c35e3e4a6b8007d24 Mon Sep 17 00:00:00 2001 From: Robert Osinski Date: Wed, 27 May 2026 13:14:35 +0000 Subject: [PATCH 08/10] text changes --- MARS language/MARS-005-CEMS-C3S-Hydrology.md | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/MARS language/MARS-005-CEMS-C3S-Hydrology.md b/MARS language/MARS-005-CEMS-C3S-Hydrology.md index 4b86ce5..4c87941 100644 --- a/MARS language/MARS-005-CEMS-C3S-Hydrology.md +++ b/MARS language/MARS-005-CEMS-C3S-Hydrology.md @@ -23,8 +23,9 @@ For this reason, we propose introducing a new MARS keyword called ‘forcing’, ### Options Considered -We propose to introduce two new MARS keywords. -The configuration keyword stores information about the model version and the current running setup in a single key. The 2nd proposed key is the forcing keyword which contains the centre identifier together with the modelName to describe the data used to drive the hydrological model. This is needed to distinguish AIFS and IFS for ECMWF, but also the DWD Cosmo and ICON models which is not doable with the existing origin keyword. +We propose introducing two new MARS keywords. +The configuration keyword stores information about the model version and the current runtime setup within a single key. The second proposed keyword, forcing, combines the centre identifier with the modelName to describe the data used to drive the hydrological model. +This distinction is required to differentiate between AIFS and IFS at ECMWF, as well as between the COSMO and ICON models at DWD, which is not possible using the existing origin keyword alone. ### Analysis From 934a1e6c5c05bcf15ccb5e9a75f1f3efd596f2ed Mon Sep 17 00:00:00 2001 From: Simon Smart Date: Mon, 29 Jun 2026 18:12:54 +0100 Subject: [PATCH 09/10] Update README index for MARS language --- MARS language/README.md | 3 +++ 1 file changed, 3 insertions(+) diff --git a/MARS language/README.md b/MARS language/README.md index 3098e93..bc3fad2 100644 --- a/MARS language/README.md +++ b/MARS language/README.md @@ -11,5 +11,8 @@ Decision records for changes and additions to the MARS language. | Item | Status | | -- | -- | | [MARS-001 Mars Model Keyword for DestinE On-Demand-Extremes DT](./MARS-001-MARS-Model-Keyword-for-DestinE-ODEDT.md) | Accepted | +| [MARS-002 Flight Levels](MARS-002-flightLevels.md) | Accepted | +| [MARS-003 Coefficient Index for Model Errors](MARS-003-model-errors-with-coeffs.md) | Accepted | +| [MARS-005 CEMS C3S Hydrology](MARS-005-CEMS-C3S-Hydrology.md) | Accepted | | [MARS-006 Land Surface tile Data](./MARS-006-Land-Surface-Tile-Data.md) | Accepted | | [MARS-007 Timespan Keyword in post-MTG2](./MARS-007-Timespan-Absence.md) | Proposed | From 671944d5801f2e0549fdff15c2953d0fd5b5257e Mon Sep 17 00:00:00 2001 From: Simon Smart Date: Mon, 29 Jun 2026 18:40:28 +0100 Subject: [PATCH 10/10] Tidy up the hydrology MARS language ADR --- MARS language/MARS-005-CEMS-C3S-Hydrology.md | 122 +++++++++++-------- 1 file changed, 73 insertions(+), 49 deletions(-) diff --git a/MARS language/MARS-005-CEMS-C3S-Hydrology.md b/MARS language/MARS-005-CEMS-C3S-Hydrology.md index 4c87941..0e417ca 100644 --- a/MARS language/MARS-005-CEMS-C3S-Hydrology.md +++ b/MARS language/MARS-005-CEMS-C3S-Hydrology.md @@ -1,73 +1,95 @@ # MARS Language Decision Record 005: CEMS and C3S hydrology data in MARS -## Status [~~Proposed~~ | **Accepted** | ~~Deprecated~~ | ~~Superseded by [ADR-XXX]~~] ## Last Updated -2025-05-19 -## Context +2026-06-20 -CEMS and C3S hydrological data are produced with different hydrological models which are driven by different atmospheric model and observational data. -The layout of the current way hydrological data is archived will change. In CEMS, the different hydrological versions for the European and the global domain go into different streams under class ce. The new layout has four distinct classes for the European CEMS / C3S and the global counterparts. -The hydrological model in the current layout is indexed using the ‘model’ keyword. This new proposed layout will also use the model keyword for indexing the hydrological model. One problem with the existing layout is that different model configurations used for producing the climatologies were referenced through the keyword date, which caused overwriting issues with the reforecast data. Therefore, the proposal includes introducing a new MARS keyword, configuration, which specifies not only the model version but also additional information about the setup. This configuration keyword is intended to be used only for the hindcasts as for all other data, there is no overlapping of different configurations at the same point in time. -Examples of different configurations used in CEMS and C3S are: -* v1, v4 -* v1-c3s-e_catchment -* v1-c3s-e_grid -* v1-c3s-ww +## Overview -The hydrological data are driven by different atmospheric data. In the old layout this was specified by the origin mars keyword, e.g., origin=ecmf/edwz/cosmo. As for ECMWF forcings will include IFS as well as AIFS, origin=ecmf is no longer sufficient to distinguish between the two models. With the specific post-processing templates, we are using in GRIB2 to encode the data, it is possible to distinguish the data and a string can be created like for example ecmf_ifs or ecmf_aifs. In general, this follows the format "centre_model", which provides more information than the current origin key. -For this reason, we propose introducing a new MARS keyword called ‘forcing’, which would more accurately represent the model used to produce the data. +CEMS and C3S hydrological data are produced by multiple different hydrological models, and these runs are driven +by different atmospheric model and observational data. Users need to be able to identify data along these two +axes. +Currently the way that hydrological data are archived is problematic. Firstly, currently this data is indexed +according to the generating model, using the `model` keyword, but this does not contain any information about +the configuration or version of the model. For reforecast data, the same date is reforecast on multiple +occasions using different model versions and configurations, and this results in disambiguation issues and +potential overwriting of data. -### Options Considered +To address this, we propose introducing an additional keyword `configuration` for hindcast data (specifically +stream `rfsd`, retrospective forcings and simulation data). Examples of different `configuration`s which +would be used in CEMS and C3S are: -We propose introducing two new MARS keywords. -The configuration keyword stores information about the model version and the current runtime setup within a single key. The second proposed keyword, forcing, combines the centre identifier with the modelName to describe the data used to drive the hydrological model. -This distinction is required to differentiate between AIFS and IFS at ECMWF, as well as between the COSMO and ICON models at DWD, which is not possible using the existing origin keyword alone. + - `v1` + - `v4` + - `v1-c3s-e_catchment` + - `v1-c3s-e_grid` + - `v1-c3s-ww` +Note that outside of hindcast data, there is no overlap of different configurations for the same point in +time, and so this additional disambiguation is not necessary. + +Secondly, the different atmospheric data used to force the hydrological simulation are currently identified +using the `origin` keyword, e.g. `origin=ecmf/edwz/cosmo`. With the introduction of the AIFS as well as the +IFS, using `origin=ecmf` is no longer sufficient to distinguish between all relevant forcings data. The same +issue is observed between the COSMO and ICON models at DWD. Sufficient data is present in the GRIB header +to identify this data further. + +As such we propose a new MARS keyword `forcing` which will combine the originating centre and the associated +atmospheric model. The values will be construted of the form `-`. + +Finally, we propose restructuring the overall archive. Currently in CEMS th edifferent hydrological versions for +the European and the global domains are archived into different `stream`s under `class` `ce`. We introduce instead +four distinct `class`es for the European CEMS / C3S and their global counterparts. ### Analysis -We did not consider other options than option 1. +Only one option was considered. ## Decision + The hydrology data will be archived under the following MARS classes: | MARS class | Name | |:-----------------:|:---------------------------------------| -| ef | EFAS (European flood awareness system) | -| gf | GLOFAS (Global flood awareness system) | -| eh | C3S European hydrology | -| gh | C3S Global hydrology | - -A MARS key forcing will be introduced which will get values like -* ecmf-ifs -* ecmf-aifs -* ecmf-era5 -* ecmf-seas -* edzw-icon -* cosmo-cosmo -* cmcc-sps -* obs - -This is the centre abbreviation dash the modelName. A configuration key will be introduced as well but only used in stream rfsd. It will contain the following values: -* v1.0 -* v1.0-catchment -* v1.0-grid -* v1.0-c3s -* v2.0 -* v2.1 -* v3.0 -* v3.1 -* v3.5 -* v4.0 -* v5.0 - +| `ef` | EFAS (European flood awareness system) | +| `gf` | GLOFAS (Global flood awareness system) | +| `eh` | C3S European hydrology | +| `gh` | C3S Global hydrology | + +A new MARS key, `forcing` will be introduced. This key will identify the data used to drive the hydrological model, +combining a centre identifier with a model name resulting in values such as: + + - `ecmf-ifs` + - `ecmf-aifs` + - `ecmf-era5` + - `ecmf-seas` + - `edzw-icon` + - `cosmo-cosmo` + - `cmcc-sps` + - `obs` + +A new MARS key, `configuration`, will also be introduced for stream `rfsd` (retrospective forcings and simulation data). This +identifies the version and setup of the model producing this dataset. This will contain values such as: + + - `v1.0` + - `v1.0-catchment` + - `v1.0-grid` + - `v1.0-c3s` + - `v2.0` + - `v2.1` + - `v3.0` + - `v3.1` + - `v3.5` + - `v4.0` + - `v5.0` ### Related Decisions + - [MARS-004 Land Data Assimilation](MARS-004-land-data-assimilation-system.md) + ## Consequences The data will be stored in newly created MARS classes, ensuring that existing datasets remain unaffected, except for the hydrology data, which will be rearchived within the new layout. The forcing and configuration MARS keywords are also applicable in other contexts. For example, the fire datasets are based on ERA5 and IFS medium-range forecasts. The configuration keyword can likewise be applied to the land data assimilation system, which operates with different model versions running in parallel to support multiple target forecasting systems that rely on this data as input. @@ -75,7 +97,9 @@ The forcing and configuration MARS keywords are also applicable in other context ## References ## Authors -- Sebastien Villaume -- Robert Osinski -- Mohamed Azhar + + - Sebastien Villaume + - Robert Osinski + - Mohamed Azhar + - Simon Smart