11/December/2023

With the release of December 2023 forecasts (10th December 2023) a new view of the SST indices time series have been included for the ENSO regions in the C3S seasonal graphical products (https://climate.copernicus.eu/charts/packages/c3s_seasonal)

In addition to the plot showing individual ensemble members a new time series plot is now available showing some of the percentiles for each month's distribution. This was already available for the IOD indices and it has been now also extended to ENSO indices.

image-2023-12-11_14-4-29.png

22/November/2023

Please note that a "data gap" issue has been documented in our C3S Seasonal Forecast known issues page affecting availability of MetOffice system 602 hindcast data for December nominal start dates (see details for issue G10. in the "Data gaps" table)

10/November/2023

Please note that a "data gap" issue has been documented in our C3S Seasonal Forecast known issues page affecting availability of MetOffice system 602 hindcast data for November nominal start dates (see details for issue G10. in the "Data gaps" table)

8/September/2023

Please note that a "data gap" issue has been documented in our C3S Seasonal Forecast known issues page affecting availability of MetOffice system 602 data for 8/August/2023 (see details for issue G10. in the "Data gaps" table)

9/August/2023

Please note that a "data gap" issue has been documented in our C3S Seasonal Forecast known issues page affecting availability of MetOffice system 602 data for 15/July/2023 (see details for issue G9. in the "Data gaps" table)

20/July/2023

New C3S seasonal forecast products available: 10m wind speed and sea ice concentration plots; additional documentation and training materials

Soon after the release of our July 2023 seasonal forecasts new features have been made available to users of the C3S seasonal forecast service:

9/June/2023

New C3S seasonal forecast products available: total column water quantities data and SST indices verification plots

With the release of our June 2023 seasonal forecasts a couple of additions have been made to the offering of the C3S seasonal forecast service:


Please also note that a "data gap" issue has been documented in our C3S Seasonal Forecast known issues page affecting availability of NCEP CFS2 data for 22/May/2023 (see details for issue G8. in the "Data gaps" table)

10/March/2023

New C3S seasonal forecast dataset and earlier publication date

With the release of our March 2023 seasonal forecasts a new dataset has been included, containing global ocean monthly data for a set of variables in the upper part of the ocean. 

More details here: Seasonal forecast monthly averages of ocean variables

Additionally, we would like to remind our users that starting today, 10th March 2023, all the products from the C3S seasonal forecast component are made publicly available on a slightly earlier schedules:

1/March/2023

Summary of new features in C3S seasonal forecast service

Around the release of our March forecast a few new features enhancing the service are being put in place, from changes in the publication date of the data and products, to the inclusion of new features in the web application displaying our graphical products, and including information about verification of the forecast systems. A new seasonal forecast dataset will be published in the CDS catalogue, as described below.


13/Jan/2023

Introduction of new features in plots and data

With the release of January 2023 C3S seasonal forecast the following changes have been introduced:


14/November/2022

Completion of ECMWF Data Handling System (DHS) move.

At 18:41 on Friday 11/November/2022 the disruption to the ECMWF DHS, where C3S seasonal forecast data is hosted, was declared as finished marking the successful completion of the move from Reading headquarters to Bologna Data Centre.

30/October/2022

Data availability during ECMWF DHS move
(Announcement date: 31/August/2022. Update: 30/October/2022)

(Announcement date: 31/August/2022. Update: 12/October/2022)

The data listed in the following table is expected to be available during the limited access period (5-6 weeks from 8/Sep/2022) caused by ECMWF move of its Data Handling System to Bologna.

Users are encouraged to download before 8/Sep/2022 any data not listed in the table they might need during that period. Any change to this schedule will be announced here.

Data streamsForecasting systems(1)Nominal start dates
daily dataMetOffice GloSea6 (system=601)Sep to Dec 1993-2016
All operational systemsSep and Oct 2022 (2)
monthly dataAll operational systemsJun to Dec 1993-2016
All operational systemsMar to Oct 2022 (2)
ECMWF SEAS5 (system=51)Oct to Dec 1993-2016
anomalies data (3)All operational systemsMar to Oct 2022 (2)

NOTES:
(1) This is the list of all currently operational forecasting systems: ECMWF SEAS5, Météo-France System8, MetOffice GloSea6 (system=601), CMCC SPSv3.5, DWD GCFS2.1, NCEP CFSv2, JMA CPS3, ECCC CanCM4i and ECCC GEM5-NEMO

(2) Real-time forecast data won't be available until its usual release date (13th of the month at 12 UTC)

(3) This also includes the data used to compute the anomalies ("ensemble mean" and "hindcast climate mean") which are available via the "monthly" CDS datasets


12/October/2022

Changes to operational forecast system from ECMWF

From November 2022 a new version of ECMWF SEAS5 output will substitute the current one. This new version (v5.1) will be labelled with the keyword system=51  

  • What are the changes in this new version of ECMWF SEAS5 data?
    • A different interpolation tool has been used to produce the 1-degree grid, both for hindcasts and real-time forecasts.
    • A new 1-degree grid, now consistent with the grid available from the other participating forecast systems. Specifically, it will have grid-points centered at half-degree latitude/longitude, and hence it has 180 values in the latitude coordinate (from -89.5 to 89.5) instead of the current 181 values (from -90 to 90)
    • A couple of additions to complete the list of available variables: Top solar incoming radiation and 1000hPa level for the 5 variables available at pressure levels. Additionally, on top of the values of runoff, for SEAS5.1 both sub-surface and surface runoff will be also available.


  • What are the implications for users of ECMWF SEAS5 data? 
    • (warning) From November 2022, only system=51 real-time forecast data will be available from the CDS
    • (warning) Users will need to use system=51 hindcast data alongside the new real-time forecasts.
      Data from the current version (system=5 ) should not be used, so those users with previously downloaded hindcast data will need to download the new version.
    • At the time of this announcement, hindcast data for October, November and December has been made available on the CDS
      • The remaining start dates (from January to September) will be processed and published progressively following the calendar order. Details on their availability can be found in the "Hindcasts" table of the Summary of available data
      • Please note that while the ECMWF DHS move hasn't been completed, not all data will be available from the CDS (details in the table above with "DATA AVAILABILITY DURING ECMWF DHS MOVE")


  • Why have these changes been introduced?
    • When ECMWF SEAS5 was released in 2017, the C3S 1-degree version was created with the default interpolation tool (emoslib ) available from MARS. With the migration of ECMWF computing infrastructure to its new Data Centre in Bologna, this tool has been discontinued. That means new real-time forecasts produced after the migration can't be produced anymore in a way consistent with the available SEAS5 hindcast in the CDS. After careful evaluation of the impact of the interpolation, it was decided to create a new version of the hindcast data. This has been labelled as SEAS5.1 and encoded with keyword system=51.
    • With this new version of SEAS5 hindcast, a couple of additional improvements were also included:
      • A new 1-degree grid consistent with the one provided for other forecast systems (see details above)
      • A couple of additions to the list of variables (see details above).

12/October/2022

Changes to stratospheric (10hPa) zonal wind plots from the October 2022 real-time forecast release

A couple of bugs have been fixed which affected the plots shown here: https://climate.copernicus.eu/charts/c3s_seasonal/

12/July/2022

An error has been identified in "sea surface temperature" and "land surface temperature" (called 'soil temperature level 1' in the CDS) data from CMCC SPSv3.5 forecasting system. The details can be found in the section "Not fixed errors" under the code E9 of our "Known issues" page

It affects the following data for those two variables:

According to CMCC report about the issue:

The problem only affects the points at the borders between the three realms (sea ice, ocean and land), and is due to a change in the land-sea or sea ice-sea mask interpolation algorithm, which was implemented in the forecasts (starting from March).
Therefore, the anomalies of the above mentioned variables show unrealistic patterns near the sea-land or sea-sea ice boundaries, because, in these grid points, the new interpolation algorithm has made the forecasts, from March onwards, inconsistent with the hindcasts.
Starting from the August 2022 real-time forecast, it will be restored the procedure used in the hindcasts.

9/May/2022

Reminder of impacts of ECMWF's Data Handling System (DHS) move to Bologna

As work to move ECMWF's DHS to Bologna progresses, the dates when users of C3S seasonal forecast data might experience disruptions are approaching.

11/ February/2022

3/January/2022

Changes to operational forecasting systems from Japan Meteorological Agency (JMA)

8/December/2021

Changes to operational forecasting systems from Environment and Climate Change Canada (ECCC)

15/November/2021

Planned changes to operational forecasting systems:

12/October/2021

An issue with sporadic anomalous values in "2m dewpoint temperature" from Météo-France System8 has been identified. The details can be found in the section "Fixed errors" under the code E9 of our "Known issues" page

29/September/2021

An error has been identified in the "total cloud cover" data from JMA CPS2 forecasting system. The details can be found in the section "Not fixed errors" under the code E8 of our "Known issues" page

It affects all available data for that variable (daily data, monthly data and anomalies) both for real-time forecasts and hindcast dates.

Due to a bug during the data ingestion to the C3S archive the values of this parameter have been divided by 100.

6/July/2021

Changes to operational forecasting systems:

23/May/2021

Changes to operational forecasting systems:

13/May/2021

Changes to operational forecasting systems:


11/Mar/2021

A data gap in MetOffice's GloSea6 forecast data has been reported as "Data gap G5" in C3S Seasonal Forecast known issues

The GloSea6 forecasts initialised on 22 and 23 February were initialised with low Arctic sea ice extents. This resulted from corrupt data used in the derivation of ocean initial conditions. The sea ice largely recovers in these forecasts, but is biased low through the whole 6-month forecast compared to neighbouring days.

Initial sea-ice conditions for different GloSea6 February 2021 start dates:

Evolution of sea-ice fraction forecasts for different GloSea6 February 2021 start dates:


2/Mar/2021

The integration into C3S seasonal forecast multi-system of ECCC forecasting systems, CanCM4i and GEM-NEMO, announced earlier (19th/January/2021) to happen with the release of March 2021 real-time forecasts has been delayed to April 2021.


16/Feb/2021

Changes to operational forecasting systems:


19/Jan/2021

Upcoming changes in the C3S seasonal forecast service planned to be implemented for the release of the March 2021 real-time forecast (13th March at 12GMT):

More details about these planned changes will be soon notified. Please note this is just an early warning about the plans for implementation of those contributions and changes to that schedule are still possible.

14/Dec/2020

With the publication of the December 2020 C3S seasonal forecasts (released on the 13th December at 12UTC) a couple of new additions have been made to the catalogue of graphical products shown at https://climate.copernicus.eu/charts/c3s_seasonal/:


26/Oct/2020

An issue in the CDS infrastructure affecting some seasonal forecast retrievals has been identified. It will be tracked as error (E7b) in the seasonal forecast known issues page.

This error prevents users from getting all available members from CFSv2-v20110310 (NCEP CFSv2) data. This issue affects retrievals done after the release of the October 2020 forecast, which happened at 12UTC on the 13th of October 2020.

It affects all data available in the high-frequency (daily/subdaily) datasets:

Members with start time at 06h,12h and 18h are not being retrieved from the archive by the CDS and just members with start time at 00h are returned.

This is currently under investigation and it will be announced here once the issue has been resolved.

The issue described above has been solved at 16:15UTC on the 26/October/2020. All retrievals should be correct now, and just those retrievals performed between 13/Oct/2020 at 12UTC and 26/Oct/2020 at 16:15UTC have been affected.


13/Oct/2020

With the release of the October 2020 real-time forecast (at 12 UTC on 13th October) some additions will be introduced to the list of available forecasting systems. Specifically:

Additionally, with the release of the November 2020 real-time forecast (at 12 UTC on 13th November), another change of forecasting systems will be included. Specifically:

Details about hindcast dates available can be found here. The complete list of parameters available for each forecasting system can be found here.

13/June/2020

All these changes have been introduced starting from June 2020, and previously produced plots haven't been affected by them.


15/May/2020

12/ May/2020

25/March/2020

11/February/2020

8/January/2020

13/December/2019

2/December/2019

29/November/2019

7/November/2019

11/October/2019

22/August/2019

5/April/2019



This document has been produced in the context of the Copernicus Climate Change Service (C3S).

The activities leading to these results have been contracted by the European Centre for Medium-Range Weather Forecasts, operator of C3S on behalf of the European Union (Delegation agreement signed on 11/11/2014). All information in this document is provided "as is" and no guarantee or warranty is given that the information is fit for any particular purpose.

The users thereof use the information at their sole risk and liability. For the avoidance of all doubt, the European Commission and the European Centre for Medium-Range Weather Forecasts have no liability in respect of this document, which is merely representing the author's view.