Category Archives: News

SPARC Science update: 12 January – 18 January

Reflections on weather and climate research. By W. Cai et al. in nature reviews: earth & environment.

Future changes in Northern Hemisphere summer weather persistence linked to projected Arctic warming. By K. Kornhuber and T. Tamarin-Brodsky in the Geophysical Research Letters.

Does Lower‐Stratospheric Shear Influence the Mesoscale Organization of Convection? By T.P. Lane in the Geophysical Research Letters.

Contrast relationships between Arctic Oscillation and ozone in the stratosphere over the Arctic in early and mid‐to‐late winter. By M. Liu and D. Hu in the Journal of Geophysical Research: Atmospheres.

On the best locations for ground-based polar stratospheric cloud (PSC) observations. By M. Tesche, P. Achtert, and M.C. Pitts in Atmospheric Chemistry and Physics.



Discussion papers – open for comment:

Consistency of total column ozone measurements between the Brewer and Dobson spectroradiometers of the LKO Arosa and PMOD/WRC Davos. By J. Gröbner et al. in Atmospheric Measurement Techniques.

Intercomparisons, Error Assessments, and Technical Information on Historical Upper-Air Measurements. By N. Imfeld et al. in Earth System Science Data.

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

Upcoming deadline: abstract submission to EGU General Assembly 2021

The deadline for abstract submission to the EGU General Assembly 2021 was extended until Wednesday 20 January at 13:00 CET.

The following is a non-exhaustive list or sessions with relevance to SPARC:

AS1.4 Subseasonal-to-Seasonal Prediction: Processes and Impacts
Convener: Daniela Domeisen | Co-conveners: Francesca Di Giuseppe, A.G. Muñoz, Frederic Vitart, Christopher White
>> Abstract submission

CL4.19 Dynamics of the atmospheric circulation in past, present and future climates
Co-organized by AS1
Convener: Michael Byrne | Co-conveners: Thomas Birner, Nicholas Lutsko, Talia Tamarin
>> Abstract submission

AS1.8 Stratospheric dynamics
Convener: Thomas Reichler | Co-conveners: Blanca Ayarzagüena, Bo Christiansen, Seok-Woo Son
>> Abstract submission

AS1.9 Atmospheric Rossby waves and Jet Dynamics, and their Impacts on Extreme Weather and Climate Events
Co-organized by NP7
Convener: Kai Kornhuber | Co-conveners: Olivia Romppainen-Martius, Rachel White, Volkmar Wirth
>> Abstract submission

AS1.11 Asian Monsoon dynamics and Atmospheric Composition
Convener: Federico Fierli | Co-conveners: Bhupesh Adhikary, Silvia Bucci, Fred Stroh
>> Abstract submission

AS1.14 Internal Gravity Waves
Co-organized by NP7/OS4
Convener: Claudia StephanECS | Co-conveners: Ulrich Achatz, Alvaro de la Camara, Riwal Plougonven, Chantal Staquet
>> Abstract submission

AS3.3 Chemistry, Aerosols and Radiative Forcing in CMIP6-era models
Convener: William Collins | Co-conveners: Piers M. Forster, Paul Griffiths, James M. Keeble, Fiona O’Connor
>> Abstract submission

AS3.5 Atmospheric composition variability and trends
Convener: Oksana Tarasova | Co-conveners: Pedro Jimenez-Guerrero, Euan Nisbet, Andrea Pozzer
>> Abstract submission

AS3.6 The role of the middle atmosphere: composition changes and feedbacks
Convener: Gabriel ChiodoECS | Co-conveners: William Ball, Mohamadou Diallo, Birgit Hassler, Peer Johannes Nowack
>> Abstract submission

AS3.17 Dynamics and chemistry of the upper troposphere and stratosphere
Convener: Marta Abalos | Co-conveners: Hella Garny, Johannes Laube, Amanda Maycock, Tanja Schuck
>> Abstract submission

AS3.22 Polar Ozone and Polar Stratospheric Clouds
Convener: Farahnaz Khosrawi | Co-conveners: Hideaki Nakajima, Michael Pitts, Ines Tritscher
>> Abstract submission

AS3.25 Understanding volcano-climate impacts and the stratospheric aerosol layer
Co-organized by CL4/NH2, co-sponsored by SPARC-SSiRC and CMIP6-VolMIP
Convener: Graham Mann | Co-conveners: Myriam Khodri, Claudia Timmreck, Matthew Toohey, Davide Zanchettin
>> Abstract submission

CL2.5 Predictions of climate from seasonal to (multi)decadal timescales (S2D) and their applications
Co-organized by EOS7/AS4/BG2/CL3.2/HS12
Convener: Taru Sandén | Co-conveners: Daniel Dörler, Dilek FraislECS, Florian Heigl
>> Abstract submission

If your SPARC-related session at EGU is not listed here, please let the SPARC office know!

SPARC Science update: 5 January – 11 January

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


The response of mesospheric H2O and CO to solar irradiance variability in models and observations. By A. Karagodin-Doyennel et al. in Atmospheric Chemistry and Physics.

Assessing trends in atmospheric circulation patterns across North America. By E.T. Smith et al. in the International Journal of Climatology.

Classification of time series of temperature variations from climatically homogeneous regions based on long‐term persistence. By D. Sarvan et al. in the International Journal of Climatology.


Discussion papers – open for comment:

Anthropogenic Reversal of the Natural Ozone Gradient between Northern and Southern Mid-latitudes. By D.D: Parrish et al. in Atmospheric Chemistry and Physics.

An Arctic Ozone Hole in 2020 If Not For the Montreal Protocol. By C. Wilka et al. in Atmospheric Chemistry and Physics.

SPARC Science update: 22 December – 4 January

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


Tracking the stratosphere‐to‐surface impact of Sudden Stratospheric Warmings. By R.J. Hall et al. in the Journal of Geophysical Research: Atmospheres.

Atmospheric blocking events: a review. By A.R. Lupo in the Annals of the New York Academy of Sciences.

Orbital forcing strongly influences seasonal temperature trends during the last millennium. By L.J. Lücke et al. in the Geophysical Research Letters.

Increased turbulence in the Eurasian upper‐level jet stream in winter: past and future. By Y. Lv et al. in Earth and Space Science.

Forecasts of “normal”. By S.J. Mason, C.A.T. Ferro, and W.A. Landman in the Quarterly Journal of the Royal Meteorological Society.

Determining Gravity Wave Sources and Propagation in the Southern Hemisphere by Ray‐Tracing AIRS Measurements. By J.A. Perrett et al. in the Geophysical Research Letters.

Long‐Term Variability and Tendencies in Middle Atmosphere Temperature and Zonal Wind From WACCM6 Simulations During 1850–2014. By K. Ramesh et al. in the Journal of geophysical Research: Atmospheres.

Influence of High Latitude Sudden Stratospheric Warming on Tropical Weather: Observations from a 205 MHz Stratosphere Troposphere Radar and Surface Meteorological Parameters. By R. Remya et al. in Earth and Space Science.

Quantifying the tropical upper tropospheric warming amplification using radio occultation measurements. By P. Vergados et al. in Earth and Space Science.

Announcement: IGAC CATCH Science Seminar Series

The first of the virtual CATCH Science Seminar Series will be held on the 14th January 2021 at 16:00 CEST. This will be a monthly seminar series which will host talks on CATCH related topics with the aim of fostering engaging scientific discussions between researchers on outstanding questions for our communities. The first seminar will be on:

“Aerosol-cloud interactions in the Arctic from an observational and modelling perspective.”

by Prof. Paul Zieger (Stockholm University)
and  Prof. Annica Ekman (Stockholm University)

The seminar will involve scientific presentations from guest speakers (2×15 min talks) followed by smaller group discussions (20 min) before ending with a group plenary session (10 min). If you are interested in attending, please register here.

SPARC Gravity Wave Symposium postponed to March 2022

The covid-19 pandemic is more acute than ever, and unfortunately the probability is high that it will not have passed before the end of 2021.

It has therefore been decided to postpone the 2021 SPARC Gravity Wave Symposium, originally scheduled to be end of September 2021, by half a year to March 28th – April 1st 2022, starting on the morning of March 28th and departing after lunch Friday April 1st. The meeting will thus be back-to-back with the EGU assembly that will be held in Vienna in the following week. The conference site of the now 2022 SPARC Gravity Wave Symposium is located in the medieval center of the vibrant city of Frankfurt.

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 www.goethe-university-frankfurt.de/87102642/Symposium

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

A 2nd announcement will be circulated in June 2021. Colleagues and friends are asked for their understanding for the decision for the postponement, which has not been made light-heartedly.

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

We look forward to your participation in 2022.

Ulrich, Joan, Kaoru, Laura, and Riwal

SPARC Science update: 15 December – 21 December

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


Perspective on Aircraft in the Stratosphere: 50 Years from COMESA through the Ozone Hole to Climate. By A.F. Tuck in the Quarterly Journal of the Royal Meteorological Society.

Effective vertical diffusion by atmospheric gravity waves. By H.-L. Liu in the Geophysical Research Letters.

Unprecedented Observations of a Nascent in Situ Cirrus in the Tropical Tropopause Layer. By I. Reinares Martínez et al. in the Geophysical Research Letters.

The Berkeley Earth Land/Ocean Temperature Record. By R.A. Rohde and Z. Hausfather in Earth System Science Data.

The Energy Modeling Forum (EMF)-30 study on short-lived climate forcers: introduction and overview. By S.J. Smith et al. in Climatic Change.

WCRP moves towards new future

The World Climate Research Program (WCRP) is moving towards a new programme structure in an era where we urgently require solutions to the challenges of climate change.

Draft WCRP Structure

In December 2020, the Joint Scientific Committee (JSC) of the World Climate Research Program (WCRP), with strong support from the leadership of all major WCRP activities, made the decision to move towards a new programme structure. This move represents a major development in the history of WCRP, reflecting its evolution from 40 years of successful fundamental climate research into an era where we urgently require solutions to climate challenges in order to address the impacts of climate change on society and all life on Earth.

The new WCRP structure has been developed by the WCRP community to support the implementation of the WCRP Strategic Plan 2018 – 2028, which addresses the climate research priorities of the next decade and beyond. It was specifically designed with the recognition that many of the challenges that we will face in the future can only be solved in partnership with other programs, each bringing in its own expertise and value.

Continue reading (WCRP webpage)

SPARC Science update: 8 December – 14 December

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



Indian monsoon derailed by a North Atlantic wavetrain. By P.J. Borah et al. in Science.


Representing model uncertainty in multi‐annual predictions. By D.J. Befort, C.H. O’Reilly, and A. Weisheimer in the Geophysical Research Letters.


Impact of Lagrangian transport on lower-stratospheric transport timescales in a climate model. By E.J. Charlesworth et al. in Atmospheric Chemistry and Physics.


Tropospheric ozone variability over Hong Kong based on recent 20‐year (2000–2019) ozonesonde observation. By Z. Liao et al., in the Journal of Geophysical Research: Atmospheres.


Dating hiatuses: a statistical model of the recent slowdown in global warming and the next one. By J.I. Miller and K. Nam in Earth System Dynamics.


Comparison of Major Sudden Stratospheric Warming Impacts on the Mid-Latitude Mesosphere Based on Local Microwave Radiometer CO Observations in 2018 and 2019. By Y. Shi et al. in Remote Sensing.


Drivers of Upper Atmosphere Climate Change. By Sarah Stanley, EOS; with reference to I. Cnossen, Analysis and Attribution of Climate Change in the Upper Atmosphere From 1950 to 2015 Simulated by WACCM‐X, JGR: Space Physics.