CONFESS results feature in ECMWF’s 2023 Winter Newsletter  

Featured Article titled: Updating land and aerosol properties to improve reanalyses and seasonal forecasts

Authors: Magdalena A. Balmaseda; Tim Stockdale; Souhail Boussetta; Retish Senan; Gianpaolo Balsamo; Angela Benedetti; Tanya Warnaars

Newsletter Number 174 – Winter 2023 (Published in January 2023)

To access the full article please visit:

Homogenized record of tropospheric aerosol for reanalyses and reforecasts

Decadal variations of tropospheric aerosols can have a strong impact on the production of reanalyses and seasonal re-forecasts. In preparation for the next generation of C3S products, CONFESS has produced a homogenous and consistent multi-decadal record of tropospheric aerosols, exploiting the atmospheric composition capabilities that the Copernicus Atmosphere Monitoring Service (CAMS) has been developing in the Integrated Forecast System (IFS-COMPO). A time-varying climatology of multiple aerosol species is calculated from data from a multi-decadal set of model  forecasts constrained by ERA5 meteorology, and with continuously evolving chemistry and aerosols driven by specified emissions. So far, we have considered the periods 1971–2019 forced by CMIP6-style emissions data (the latest version of CEDS, together with GFED for fire emissions), and 2003–2020 forced by CAMS emissions. Creating data back to 1940 will be straightforward once the ERA5 reanalyses are complete for that period. The aerosol records are then smoothed with a nine-year running mean to represent decadal variability. The resulting product has the added advantage that the last nine years can be used as a representation of the current climate aerosol values for NWP. We plan to use time-varying aerosol climatologies produced in this way for the ECMWF model versions that will be used for the next generation of ECMWF seasonal forecasts SEAS6 and the upcoming C3S reanalyses ERA6. Having an up-to-date aerosol climatology that is consistent with the latest CAMS aerosols is also helpful in allowing us to explore the impact of interactive aerosols on numerical weather predictions

 Change in July vertically integrated aerosol [mg/m2] between 1975 (left) and 2015 (right) for selected aerosol species. The effects of increased forest fires at high latitudes, changes in nitrogen chemistry affecting fine nitrate levels, pollution controls in Europe and North America, and emissions growth in India and the Middle East are all visible. Sulphate aerosols over China have peaked and are now declining.

CONFESS 2nd General Assembly

CONFESS hosted its second General Assembly with project partners on the Wednesday, 1st December 2021 from 09:00 UK Time.

All work package leaders and most of the project team members were present and presented the progress of the project.

Presentations from the meeting are available below.

9:00-9:05WelcomeMagdalena Alonso Balmaseda (ECMWF)
9:05-9:10 WP1 updateConstantin Ardilouze (MF)
9:10-9:25 Comparison of LAI trendsGildas Dayon (MF)
9:25-9:40 Impacts of interannually varying LAI vs. evolving LULCSouhail Boussetta (ECMWF)
9:40-9:50Improved effective vegetation cover parameterizationFransje van Oorschot (CNR-ISAC)
9:50-10:00Multi-model study on the effect of inter-annually varying LAIFransje van Oorschot (CNR-ISAC)
10:00-10:05WP2 updateRoberto Bilbao (BSC)
10:05-10:15Tropospheric and volcanic aerosol developmentsTim Stockdale (ECMWF)
10:15-10:25Preliminary evaluation of the CONFESS biomass burning experiments with the ECMWF ENS system.Angela Benedetti (ECMWF)
10:25-10:35An empirical model for predicting biomass emissions.Pablo Ortega (BSC)
10:35-10:45 Comparison of CMIP6, EVA and EVA_H volcanic forcings and climate response in EC-Earth3.Roberto Bilbao (BSC)
10:45-11:00  Coffee break 
11:00-11:05WP3 updateLauriane Batté (MF)
11:05-11:20 Impact of interactive vegetation on seasonal prediction in the CNRM-CM modelGildas Dayon (MF)
11:20-11:35 Effects of the realistic vegetation cover on predictions at seasonal and decadal time scalesAndrea Alessandri / Emanuele DiCarlo (CNR-ISAC)
11:35-11:50 Time-varying vegetation: Initial results from ECMWF seasonal hindcastsRetish Senan (ECMWF)
11:50-12:05 Impact of volcanic eruptions on decadal predictionsRoberto Bilbao (BSC)
WP4 & closure 
12:05 – 12:10WP4 -Coordination and DisseminationTanya Warnaars (ECMWF)

Improved Vegetation Variability

A new deliverable presents the results of improved vegetation variability on surface fluxes modeled with offline land surface models. In this deliverable, we present the integration of the unprecedented vegetation information, from the latest satellite campaigns in the frame of Copernicus, into the land surface models (LSMs) used for reanalysis and initialization of the seasonal to decadal prediction systems. Observational Land Cover (LC) and Leaf Area Index (LAI) from CONFESS deliverable D1-1 are implemented as boundary conditions for the CHTESSEL (ECMWF), EC-Earth HTESSEL-LPJGuess (CNR) and the ISBA-CTRIP (Météo-France) land surface models. The effects of the improved representation of vegetation variability from observations on the LSMs has been evaluated in offline simulations forced by ERA5 atmospheric forcing.

Here we present the effects of seasonally and inter-annually varying LAI (sensitivity experiment), based on Copernicus observational data, on modelled evaporation, compared to evaporation modelled using seasonally varying LAI only (control experiment). Evaporation was evaluated using DOLCEv3 evaporation as reference. The figure below shows the effect of inter-annually varying LAI on the correlation of inter-annual anomaly evaporation for the three models with respect to the reference. The correlation consistently improves (blue colours) for ECMWF and CNR models, with the largest effects in regions with transitional climates. Also for the MF model considerable improvements were found.

The knowledge from the sensitivity analysis in this report is driving the selection of better solutions and configurations to include for the initialization/simulation of the predictions in CONFESS WP3. You can read more about the results in D1.2 Improved vegetation variability.

Upcoming Presentations of CONFESS

The month of May will be a busy time for the CONFESS consortium who will be presenting at a number of prestigious international events. The end of May is when EGU will hold their Annual General Assembly meeting, which is the same week as the ESA-Living Planet Symposium. These events will see our consortium members travelling to Vienna, where A. Alessanndri (CNR-ISAC) will host a session at EGU where five presentations related to CONFESS will be given. A strong representation will also be in Bonn to present the work of CONFESS at the European Space Agency’s 2022 Living Planet Symposium, which is held every three years. This is an exiting time for the project as we are eager to share our results with the community who can benefit from our findings as well as feedback on our project achievements. These and future presentations over the summer of 2022 are listed in our presentation page.

CONFESS General Assembly

CONFESS hosted its first public General Assembly online on the Wednesday, 1st December 2021 from 09:00 UK Time.

Over 70 participants from Europe and beyond heard about the objectives and progress of the project.

Presentations from the meeting are available below.

9:00 – 9:40 Welcome and Introduction to the GA

9:00-9:10Jean-Noel Thepaut (Director of Copernicus department at ECMWF)Welcome 
9:00-9:20Magdalena A. Balmaseda (Project Leader)Introduction to the GA and practicalities

9:20-10:20 CONFESS in the Copernicus Context

9:20-9:50Hans Hersbach (ECMWF, invited)C3S Earth System Reanalyses: progress and planned evolution
9:50-10:20Antje Innes (ECMWF, invited)Updates to CAMS reanalyses activities and synergies with climate

10:30 – 12:00 WP1: Continental Surfaces Impact (soil & vegetation, land-use)

10:30-10:45Constantin Ardilouze (Meteo France)Overview of progress in WP1
10:45-11:00Souhail Boussetta (ECMWF)Task 1.1 Harmonization of Copernicus observational records with focus on vegetation
11:00-11:15Andrea Alessandri (CNR)Task 1.2. Implementation in HTESSEL/SURFEX to assess interannual variability
11:15-11:30Gildas Dayon (MeteoFrance)Task 1.3: Sensitivity of land surface conditions to dynamic vegetation
11:30-11:40Andrea Alessandri (CNR)Outreach and dissemination. Links to other international projects
11:40-12:00Questions and discussion

13:00 – 14:15 WP2  Aerosols in Troposphere and Stratosphere

13:00-13:15Roberto Bilbao (BSC)Overview of Progress in WP2
13:15-13:30Tim Stockdale (ECMWF)Task 2.1 Harmonization of CMIP6 and C3S/CAMS data with IFS (decadal variations)
13:30-13:45Angela Benedetti (ECMWF)Task 2.2. Capability to react to hazardous events: Biomass burning.  PART A: Experimental set up and Biomass Climatology
13:45-14:00Etienne Tourigny (BSC)Task 2.2 Capability to react to hazardous events: Biomass burning. PART B:  Empirical model for biomass burning emissions
14:00-14:15Tim Stockdale (ECMWF)Task 2.3 Capability to react to volcanic eruptions events
14:30-15:00Joao Teixeira (UK MetOffice, Invited)Coupling fire with vegetation  in the UK MetOffice Earth System Model
15:15-15:45Julia Green (University of Berkeley, Invited)Regional atmosphere-terrestrial biosphere feedbacks

15:45-16:15 WP3 Integration and testing in initialised forecast and multi-year integration and Final Discussion

15:45-16:00Lauriane Batte (Meteo France)Overview and progress: Experimental protocol
16:00-16:15Final discussion 

Year 1 highlights

The first period of the CONFESS project running from 1 November 2020 to 31 October 2021 has just concluded, and an impressive list of results has been achieved.


  • A harmonized observational Leaf Area Index (LAI) dataset covering the 1993-2019 period has been finalized and disseminated to CONFESS partners.
  • The Land Use / Land Cover (LULC) dataset has been adapted to IFS Vegetation Types and shared with partners
  • The FCover dataset has been retrieved and finalized to support modelling in task 1.2 and 1.3.
  • Annual maps of LULC derived from LUH2 have been produced consistently with SURFEX plant functional types
  • Vegetation and atmospheric input (ERA5 hourly forcing) have been prepared separately for each partner.
  • A list of land model output (variables, frequency) has been agreed and shared between partners.
  • Spin-up of Land-only simulations with prescribed LAI is about to be run.
  • Performed parameter estimation and optimization for the implementation of the effective vegetation-cover parameterization based on FCover and LAI data: the observational data of FCover was retrieved for the time period 1999-2019 and harmonized using a CDF matching approach consistent with what was done  by ECMWF for the LAI data .
  • The observational FCover and LAI data have been first categorized by land cover type as identified in the observational ESA CCI land cover dataset on a 9km (Tco1279) grid.
  • Performed a historical land-only simulation with interactive vegetation.


  • A new approach has been developed to derive a new version of the CAMS aerosol climatology, using the latest IFS version with full chemistry and aerosol, and including 14 aerosol types.
  • A new climatology will be derived over a multi-decadal period to allow the creation of a time-varying climatology, to obtain both a more accurate representation of the present -day climatology, and a much more accurate representation of the time-evolution at a regional scale.
  • A test-suite for this new approach has been successfully implemented.
  • A climatology was created from the Global Fire Assimilation System (GFAS) developed and maintained by CAMS, which is due to be made available in the Atmosphere Data Store.
  • Observed emissions from GFAS are already implemented in the IFS ENS which will be used to carry out the experiments.
  • The modelling first on FireCCI burned area at 0.25 deg resolution aggregated over 12 months periods centered around the peak month (for each grid point) has started.


  • The experimental protocol for the experiments in WP3 has been developed, covering all the experiments in the WP (Tasks 1, 2 and 3).
  • Production of re-forecasts with prescribed changes in land surface conditions will start in the second year of the project.

Vegetation dataset of Land Use/Land Cover and Leaf Area Index

A new deliverable provides the land use land cover data based on the ESA-CCI/C3S, and the Leaf Area Index data for the period of 1993 to 2019, based on harmonization of the CGLS/C3S data and the AVHRR based data. These data will be prescribed into the offline and coupled model to assess the impact of their inter-annual variability on reanalysis and seasonal forecast.

The Vegetation dataset of land use/land cover (LU/LC) and Leaf Area index (LAI) are essential for the CONFESS project. One of the main targets of this project is improving the usability of the information delivered across different Copernicus Services within the land-atmosphere coupled system. It aims at using new Earth Observations of LU/LC and vegetation states and the impact of their inter-annual variability on reanalysis and seasonal forecast.

CONFESS uses the LU/LC and LAI data from the Copernicus Climate Change Service (C3S) and the Copernicus Global Land Services (CGLS) for the period from 1993 to 2019. The LU/LC data is provided at a yearly frequency and adapted to the BATS classification as used within the ECMWF Integrated Forecasting System (IFS). The LAI data provided every 10-days, is extended from the 1999 to 1993 with the AVHRR-based data available through the C3S and interpolated to 1km spatial resolution. The harmonisation of the LAI data from the two data sources is assured with a CDF matching procedure.

You can read more about the datasets in D1.1 Vegetation dataset of Land Use/Land Cover and Leaf Area Index.

CONFESS – 9 months in

CONFESS has completed its first nine months of its planned activities, resulting in 7 deliverables, of which 8 are publicly available.

CONFESS partners are busy preparing first data sets in the form of harmonized CAMS and CMIP6 datasets for aerosols that are due to be published in October 2021.

Regular meetings are taking place both within the consortium as well as with stakeholders from the Copernicus Climate Change Service to ensure the results of the project will add value,

If you want to learn more about the project, please do not hesitate to contact us.

Experimental protocol for land and aerosol forcing re-forecasts

A new document has been published that provides a description of the re-forecasts planned in WP3 to assess the impact of improved boundary forcings in an initialized climate prediction setting.

Several sets of experiments are planned. A first category of experiments relate to developments in WP1 on the representation of time-varying land use and vegetation in land surface models and reanalyses, which are key ingredients for seasonal forecasting systems and multi-annual forecasting systems operated in the framework of the Copernicus Climate Change Service (C3S). Another category of experiments will evaluate the impact of tropospheric and volcanic aerosol forcing on seasonal and multi-annual experiments.

This document details plans for each model / system as of Month 9 of the project. In some cases, which are specified, some details of the experimental setup are yet to be decided based on results from analyses in WP1 and WP2. However, this deliverable provides a first framework for WP3 activities and leaves room for future adjustments, to be agreed among partners, when needed.

You can read more about the protocol in D3.1 Experimental protocol for land and aerosol forcing re-forecasts.