All posts by Mareike@WCRP/SPARC

New assessment report by the SPARC S-RIP activity available as early-online release

In a comprehensive review, the SPARC S-RIP activity has conducted a coordinated intercomparison of reanalysis data sets with respect to key diagnostics. The results can be used to provide guidance on the appropriate use of reanalysis products in scientific studies of relevance to SPARC and beyond.

Find SPARC Report No. 10,

SPARC Reanalysis Intercomparison Project (S-RIP) Final Report

This report is an early online release of the final report of the SPARC S-RIP Activity. This version has been reviewed in a blind peer-review process, and type-setting has been done to produce this early version of the report. To finalise the report, editorial work needs to be completed, which will **not change the contents** of the report.

edited by SPARC S-RIP activity team: and

Submit your abstract to the 102nd AMS Annual Meeting until 1 September 2021

The 102nd Americal Meteorological Society (AMS) Annual Meeting will be held on 23–27 January 2022 in Houston, TX.

The meeting will be in person with some virtual components. More information will become available on the AMS 2022 website ( during this month. Registration rates will be posted in mid-July. The abstract submission deadline is 1 September 2021.

Please find the Call for Papers and the Student Award opportunities, including travel grants, on the MA Conference webpage (

A number of conferences of interest to the SPARC community have been organised for this meeting. The following is a non-exhaustive list:

21st Conference on Middle Atmosphere

35th Conference on Climate Variability and Change

24th Conference on Atmospheric Chemistry

10th Symposium on the Madden-Julian Oscillation and Sub-Seasonal Monsoon Variability

Four new WCRP/CORDEX Flagship Pilot Studies

In 2016 CORDEX Flagship Pilot Studies (FPSs) were established with the aim of improving the capability of the models in reproducing regional climate features and producing actionable information for impact studies. FPSs are intended to specifically tackle scientific questions for any given region of the world for which current RCMs are still unable to reproduce the regional climate features adequately.

The FPSs focus on extreme events with large socioeconomic impacts and can for example handle intensive rain, droughts, floods and heatwaves.

Current FPSs defined by CORDEX are summarised in a recently published CORDEX newsletter, as well as on the CORDEX webpage.

Prize Challenge to improve Sub-seasonal to Seasonal Predictions using Artificial Intelligence

Improved sub-seasonal to seasonal (S2S) forecasts could enhance food security, the sustainable management of energy and water resources, and reduce disaster risk by providing earlier warnings for natural hazards.

The World Meteorological Organization (WMO) has launched a competition to improve, through Artificial Intelligence and/or Machine Learning techniques, the current precipitation and temperature forecasts for 3 to 6 weeks into the future from the best computational fluid dynamic models available today.

All the codes and scripts will be hosted at Renkulab, developed by the Swiss Data Science Center, and training and verification data will be accessible from the European Weather Cloud and IRI Data Library. Data access scripts will be provided. After the competition, open access will be provided to all the codes and results.


  • Open since: 1st June 2021
  • Closes: 31st October 2021
  • Winners announced: Early February 2022

Prizes for the top three submissions

  • Winning team: CHF 15 000
  • Second team: CHF 10 000
  • Third team: CHF 5 000

Competition website

This challenge is part of the Subseasonal-to-Seasonal Prediction Project (S2S Project), coordinated by the World Weather Research Programme (WWRP)/World Climate Research Programme (WCRP), in collaboration with the Swiss Data Science Center (SDSC) and the European Centre for Medium-Range Weather Forecasts (ECMWF).

To get the announcement, click here.

Second announcement: SPARC Gravity Wave Symposium 2022

This is the second announcement for the 2022 SPARC Gravity Wave Symposium, scheduled to be in the week of March 28th – April 1st 2022 starting on the morning of March 28th and departing after lunch Friday April 1st. The conference site ( is located in the medieval center of the vibrant city of Frankfurt:

At the same time, we will continue monitoring the development of the COVID-19 pandemic and decide in due time whether we move fully to an online format or whether we will go for a hybrid solution, offering all those participants online participation who do not want or are not able to do the trip (decision dates see below).

This SPARC symposium is a continuation of a series of successful similar GW meetings lead-organized by Kevin Hamilton, Joan Alexander, Kaoru Sato, Fuqing Zhang and others over the past couple of decades. The tentative title of the next year’s symposium will be “Atmospheric gravity waves: towards a next-generation representation in weather and climate models”. Research on all aspects of atmospheric gravity waves, including newly emerging topics, will be welcomed but some particular emphases will be given to measurements, simulations, and numerical and theoretical developments, especially those confronting, challenging, and advancing the present-day treatment of gravity waves in atmospheric models.

The web site of the meeting (with information on travel and lodging to be placed there in due time) is

Limited travel-support funds for early-career scientists are available. Those concerned will be asked to submit an informal application together with an abstract of the work they want to present (deadline see below)

The time line of key dates is as follows:

  • End of September 2021: Call for abstracts
  • October 31st 2021: Support application deadline
  • November 15th 2021: Abstract submission deadline
  • December 13th 2021:
    • Finalization of the program.
    • Decision on early career travel support applications.
    • Decision whether the meeting will be fully online, without on-site component. This will only be the case if the pandemic makes travelling impossible even within Europe.

A 3rd announcement (call for abstracts) will be circulated in September 2021.

Co-conveners: Ulrich Achatz, Joan Alexander, Kaoru Sato, Laura Holt, and Riwal Plougonven
Meeting secretary: Aurelia Müller

We look forward to your participation.

Best Regards,

Ulrich, Joan, Kaoru, Laura, and Riwal

CAIRT mission proposal selected to compete for Earth Explorer 11 – call for membership to the mission advisory group

As part of ESA’s commitment to develop and build satellite missions that push the boundaries of satellite technology and Earth science, four new mission ideas – Cairt, Nitrosat, Seastar and Wivern – have been selected to enter pre-feasibility study and compete to be the eleventh Earth Explorer mission.

Cairt – short for changing-atmosphere infrared tomography – would provide the measurements needed to make a necessary step change in understanding the links between climate change, atmospheric chemistry and dynamics in the altitude range of about 5 to 120 km. It would focus on the processes that couple atmospheric circulation, composition and regional climate change, providing critical observations not available from existing or planned satellite missions. Cairt would be the first limb-sounder with imaging Fourier-transform infrared technology in space.

Pre-feasibility studies will start in due course, after which further down-selections will be made in 2023 and 2025, with a view to launching the successful Earth Explorer 11 mission in 2031–2032.

Read the full announcement on ESA’s webpage

The Agency has now opened a call for membership to the four respective Mission Advisory Groups (MAGs). These groups will be established after summer to advise ESA on the respective mission concepts.  Mission Advisory Groups play an active role in providing advice on activities supporting the scientific definition and preparation of the mission concept during consolidation and preparation of the mission requirements.

The Call is open to scientific experts with relevant scientific or technical expertise, with nationality and residence in one of the 22 ESA Member States.

The strict deadline for submission of applications is 5th July 2021, 12:00 (noon) CEST. Early registration is encouraged.

Further information on the mission candidates and the role and terms of reference of the MAGs is provided on the Call website:

SPARC Science update: 08 June – 14 June

A selection of new science articles from the past week of interest to the SPARC community (a SPARC Office choice).

Harnessing stratospheric diffusion barriers for enhanced climate geoengineering. By N.O. Aksamit et al., in Atmospheric Chemistry and Physics.

Anomalous changes of temperature and ozone QBOs in 2015−2017 from radiosonde observation and MERRA-2 reanalysis. By X. Bai et al., in Earth and Planetary Physics.

Differences in the quasi-biennial oscillation response to stratospheric aerosol modification depending on injection strategy and species. By H. Franke, U. Niemeier, and D. Visioni in Atmospheric Chemistry and Physics.

Persistent model biases in the CMIP6 representation of stratospheric polar vortex variability. By R.J. Hall et al., in the Journal of Geophysical Research: Atmospheres.

Unknown eruption source parameters cause large uncertainty in historical volcanic radiative forcing reconstructions. By L.R. Marshall et al. in the Journal of Geophysical Research: Atmospheres.

SPARC Science update: 01 June – 07 June

A selection of new science articles from the past week of interest to the SPARC community (a SPARC Office choice).

Tropical Stratospheric Circulation and Ozone Coupled to Pacific Multi-Decadal Variability. By F. Iglesias-Suarez et al., in the Geophysical Research Letters.

Robust asymmetry of the future Arctic polar vortex is driven by tropical Pacific warming. By S. Matsumura, Y. Yamazaki, and T. Horinouchi in the Geophysical Research Letters.

Combined Effects of Global Warming and Ozone Depletion/Recovery on Southern Hemisphere Atmospheric Circulation and Regional Precipitation. By J. Mindlin et al., in the Geophysical Research Letters.

The stratospheric Brewer–Dobson circulation inferred from age of air in the ERA5 reanalysis. By F. Ploeger et al., in Atmospheric Chemistry and Physics.

Interacting tipping elements increase risk of climate domino effects under global warming. By N. Wunderling et al., in Earth System Dynamics.

Discussion papers – open for comment:

Weakening of Antarctic Stratospheric Planetary Wave Activities in Early Austral Spring Since the Early 2000s: A Response to Sea Surface Temperature Trends. By Y. Hu et al., in Atmospheric Chemistry and Physics.

First WCRP Climate Research Forum for Europe and Western Asia

WCRP Climate Research Forum for Europe and Western Asia
“Climate research priorities for the next decade”
9 June 2021,
09:00 – 12:30 Central European Summer Time
– Online –

The World Climate Research Programme (WCRP) local organizing committee for the Europe and Western Asia region warmly invites you to the upcoming WCRP Climate Research Forum on “Climate research priorities for the next decade.” 

This Forum will begin with an overview of WCRP from the Chair and Vice Chair of the WCRP Joint Scientific Committee (the scientific steering body of WCRP), Detlef Stammer and Helen Cleugh, followed by presentations highlighting key WCRP Activities, including several of the WCRP Core Projects, the Coupled Model Intercomparison Project (CMIP), the Coordinated Regional Climate Downscaling Experiment (CORDEX), and the WCRP Lighthouse Activities (My Climate Risk, Safe Landing Climates, Explaining and Predicting Earth System Change, and the WCRP Academy).  

This will be followed by two moderated panel discussions: 

Panel 1: Opportunities to broaden WCRP science engagement

Panel 2: Opportunities to strengthen support for WCRP science

This is the fifth in a series of online Climate Research Forums, aimed at exchanging ideas, discussing new activities and opportunities being developed by WCRP, and exploring ways that our climate science community of scientists, partner programs, funders, and end-users can engage towards building “a world that uses sound, relevant, and timely climate science to ensure a more resilient present and sustainable future for humankind.”  

The Forum is without charge and is open to all, but we do ask that you register. 

Further information and details of how to register can be found either in the attached brochure or at:  

The Forum will be recorded, and the recording will be posted online on the WCRP webpage after the event. 

SPARC Science update: 25 May – 31 May

A selection of new science articles from the past week of interest to the SPARC community (a SPARC Office choice).

The Influence of Stratospheric Soot and Sulfate Aerosols on the Northern Hemisphere Wintertime Atmospheric Circulation. By J. Coupe and A. Robock in the Journal of Geophysical Research: Atmospheres.

‘Hybrid’ scientific conferences aim to offer the best of in-person and virtual meetings. By K. Langin in Science Careers.

Central role of nitric oxide in ozone production in the upper tropical troposphere over the Atlantic Ocean and western Africa. By I. Tadic et al., in Atmospheric Chemistry and Physics.

The nature of the trend in global and hemispheric temperatures. By U. Triacca and A. Pasini in the International Journal of Climatology.

Discussion papers – open for comment:

Methodology to obtain highly resolved SO2 vertical profiles for representation of volcanic emissions in climate models. By O.S. Sandvik et al., in Atmospheric measurement Techniques.