On September 16th, the International Day for the Preservation of the Ozone Layer, the International Ozone Commission has released the following satement:

The International Ozone Commission, on the 33th anniversary of the Montreal Protocol, reports successes and remaining challenges for understanding ozone layer recovery

September 16th is the International Day for the Preservation of the Ozone Layer, celebrating the 1987 anniversary of the Montreal Protocol on Substances that Deplete the Ozone Layer. The Montreal Protocol is the globally ratified treaty that controls the production and consumption of ozone depleting substances (ODSs) and many replacements for these substances.

The theme of the International Day for the Preservation of the Ozone Layer on 16 September 2020 is: “Ozone for life: 35 years of ozone layer protection”. This 35-year period marks the adoption of the Vienna Convention for the Protection of the Ozone Layer. The Convention mandates a worldwide ozone research effort to understand and measure the Earth’s critically important ozone layer. Significant anomalous Antarctic and Arctic ozone events in the 2019-2020 period demonstrated the necessity of these ongoing measurements and associated research.

The Antarctic ozone hole in September-October 2019 was relatively small compared to the very large and deep ozone holes observed in the 1990-2010 period. The ozone hole occurs every year since the early 1980s and is caused by high levels of human-produced Ozone Depleting Substances (ODS) in our atmosphere. ODS concentrations are still high enough to cause severe spring-time ozone destruction, and the gradual decline of ODSs is contributing to an improvement of Antarctic ozone levels. However, the main cause of the weak 2019 hole was the very active meteorological conditions in the AugustSeptember 2019 period compared to prior years. This active stratospheric meteorology drove an early shut-down of the ozone depleting conditions. The origin of this abnormal meteorology is an ongoing research topic.

In sharp contrast, Arctic ozone depletion, which is generally much weaker than its Antarctic counterpart, was particularly severe in the spring of 2020. This depletion was caused by a combination of factors that primarily arose due to unusually weak stratospheric meteorological weather events in the December through March period compared to all prior years. Typically, these events drive movements of ozone-rich air through the polar vortex. The lack of weather events led to an unusually strong and cold Arctic polar vortex during the 2019-2020 winter, and a lack of ozone transport. The combination of prolonged cold temperatures (enabling strong ozone depleting reactions) and lack of ozone transport
caused this rare large Arctic ozone depletion.

Total atmospheric ODS levels continue to decrease around the world according to the findings of the Scientific Assessment of Ozone Depletion: 2018 [WMO/UNEP, 2018] although the decrease of CFC-11 levels, one of the main ODS, has slowed in recent years. The 20-year atmospheric ODS decline contributes to the improvements observed for the ozone hole. Without measurements and scientific analysis, the slowing in the decrease of CFC-11 would not have been detected.

Our ability to follow significant ozone events is crucially dependent on satellite, balloon, and groundbased ozone observing systems. Maintenance and continuation of ozone and ancillary observations is vital for improving our understanding of interactions between climate change and ozone depletion, for ozone layer recovery studies, and for research into potential future impacts on the ozone layer. The events of 2019-2020, coupled with the celebration of the Vienna Convention’s 35th Anniversary help us recall the Convention’s Article 3: “The Parties undertake to promote or establish, … , joint or complementary programmes for systematic observation of the state of the ozone layer and other relevant parameters.” The Vienna Convention’s foresight allows scientists to closely follow and understand our changing ozone layer.

Due to the current COVID-19 pandemic, the 2020 Quadrennial Ozone Symposium, which was to be held in Seoul, South Korea on 5-9 October 2020, has been postponed to 2021 during the same period.

Find the complete statement

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

Global-scale distribution of ozone in the remote troposphere from the ATom and HIPPO airborne field missions. By I. Bourgeois et al. in Atmospheric Chemistry and Physics.

Downward migration of the zonal‐mean circulation in the tropical atmosphere. By K. DallaSanta and E.P. Gerber in the Geophysical Research Letters.

Effect of deep convection on the tropical tropopause layer composition over the southwest Indian Ocean during austral summer. By S. Evan et al. in Atmospheric Chemistry and Physics.

Predictability of European Winters 2017/2018 and 2018/2019: Contrasting influences from the Tropics and stratosphere. By J. Knight et al. in the Atmospheric Science Letters.

Earth System Model Evaluation Tool (ESMValTool) v2.0 – diagnostics for emergent constraints and future projections from Earth system models in CMIP. By A. Lauer et al. in Geoscientific Model Development.

Stratospheric carbon isotope fractionation and tropospheric histories of CFC-11, CFC-12 and CFC-113 isotopologues. By M. Thomas et al. in Atmospheric Chemistry and Physics.

The effect of interactive ozone chemistry on weak and strong stratospheric polar vortex events. By J. Oehrlein, G. Chiodo, and L.N. Polvani in Atmospheric Chemistry and Physics.

Discussion papers – open for comment:

A Global Total Column Ozone Climate Data Record. By G.E. Bodeker et al. in Earth System Science Data.

Influence of ENSO on entry stratospheric water vapor in coupled chemistry-ocean CCMI and CMIP6 models. By C.I. Garfinkel et al. in Atmospheric Chemistry and Physics.

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

Seasonal Variation of the Quasi‐Biennial Oscillation Descent. By L. Coy et al. in the Journal of Geophysical Research: Atmospheres.

CMIP6 climate models imply high committed warming. By C. Huntingford, M.S. Williamson, and F.J.M.M. Nijsse in Climatic Change.

Lidar observations of large‑amplitude mountain waves in the stratosphere above Tierra del Fuego, Argentina. By N. Kaifler et al. in Scientific Reports.

Far‐ranging impact of mountain waves excited over Greenland on stratospheric dehydration and rehydration. By R. Kivi et al. in the Journal of Geophysical Research: Atmospheres.

Sensitivity of trends to estimation methods and quantification of subsampling effects in global radiosounding temperature and humidity time series. By SY Souleyname et al. in the International Journal of Climatology.

The anomalous 2019 Antarctic ozone hole in the GEOS Constituent Data Assimilation System with MLS observations. By K. Wargan et al. in the Journal of Geophysical Research: Atmospheres.

Seasonal Forecasts of the Twentieth Century. By A. Weisheimer et al. in the Bulletin of the American Meteorological Society.

Discussion papers – open for comment:

Upward transport into and within the Asian monsoon anticyclone as inferred from StratoClim trace gas observations. By M. von Hobe et al. in Atmospheric Chemistry and Physics.

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

Projecting ozone hole recovery using an ensemble of chemistry–climate models weighted by model performance and independence. By M. Amos et al. in Atmospheric Chemistry and Physics.

Historical total ozone radiative forcing derived from CMIP6 simulations. By R. Bieltvedt Skeie et al. in npj Climate and Atmospheric Science.

Airborne measurements and large-eddy simulations of small-scale gravity waves at the tropopause inversion layer over Scandinavia. By S. Gisinger, J. Wagner, and B. Witschas in Atmospheric Chemistry and Physics.

How can we improve the driving of the Quasi‐Biennial Oscillation in climate models? By A. Hertzog in the Journal of Geophysical Research: Atmospheres.

Decline in Temperature Variability on Svalbard. By  S. Hølleland and H.A. Karlsen in the Journal of the Climate.

Tropical cyclones impact on tropopause and the lower stratosphere vapour based on satellite data. By B. Jiang et al., in the Atmospheric Science Letters.

First Direct Observational Evidence for Secondary Gravity Waves Generated by Mountain Waves over the Andes. By M. Kogure et al. in the Geophysical Research Letters.

Seasonal and Latitudinal Variability of the Gravity Wave Spectrum in the Lower Stratosphere. By E.A. Lindgren et al. in the Journal of Geophysical Research: Atmospheres.

The Interaction between Moist Convection and the Atmospheric Circulation in the Tropics. By L. Tomassini in the Bulletin of the American Meteorological Society.

Discussion papers – open for comment:

Technical Note: First comparison of wind observations from ESA’s satellite mission Aeolus and ground-based Radar wind profiler network of China. By J. Guo et al. in Atmospheric Chemistry and Physics.

Radiosounding HARMonization (RHARM): a new homogenized dataset of radiosounding temperature, humidity and wind profiles with uncertainty. By F. Madonna et al. in Earth System Science Data.

What:  The second phase of the Tropospheric Ozone Assessment Report (TOAR-II) is beginning with an open call to the research community to build the assessment and coordinate new studies on ozone’s global distribution and trends, as well as impacts on human health, vegetation and climate. To learn more about, satisfy your curiosity, or to get involved with this grass roots effort you are invited to attend the TOAR-II Quickstart Event on September 16, 2020.  This 90-minute virtual event will include a series of short presentations from the TOAR-II Steering Committee covering the scope and goals of the Activity, followed by a Q&A session.

When:  Wednesday, September 16, 12:00-13:30 UTC*
*the webinar will be recorded for those who cannot attend

Where:  Online, pre-register here*:
https://attendee.gotowebinar.com/register/330820367512943631
*seats are limited so please pre-register to ensure your place; you may also register on September 16

Agenda:

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Find more information on the webpage:  https://igacproject.org/activities/TOAR/TOAR-II

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

Observed Temperature Changes in the Troposphere and Stratosphere from 1979 to 2018. By A.K.l Steiner et al. in the Journal of the Climate.

Inconsistencies between chemistry–climate models and observed lower stratospheric ozone trends since 1998. By W:T: Ball et al. in Atmospheric Chemistry and Physics.

Investigating stratospheric changes between 2009 and 2018 with halogenated trace gas data from aircraft, AirCores, and a global model focusing on CFC-11. By J.C. Laube et al. in Atmospheric Chemistry and Physics.

Long-term trends and impacts of polar cold airmass in boreal summer. By Q. Liu, G. Chen, and T. Iwasaki in the Environmental Research Letters.

Atmospheric gravity waves observed in the nightglow following the 21 August 2017 total solar eclipse. By I. Paulino et al. in the Geophysical Research Letters.

The Unique Characteristics and Potential Mechanisms of the MJO‐QBO Relationship. By N. Sakaeda, J. Dias, and G. Kiladis in the Journal of Geophysical Research: Atmospheres.

Observed Hemispheric Asymmetry in Stratospheric Transport Trends from 1994‐2018. By S.E. Strahan et al. in the Geophysical Research Letters.

A new book is now available about the Montreal Protocol on Protection of the Ozone Layer.

The book “Saving our Skins”, written by Richard McKenzie is an insider’s account of the most successful international environmental action ever undertaken: the Montreal Protocol on Protection of the Ozone Layer. Saving our Skins is the story of how McKenzie and his colleagues at New Zealand’s National Institute of Water & Atmospheric Research in Lauder – a research laboratory housed on a sheep and cattle station at the bottom of the country – helped ensure the success of the Montreal Protocol. Ultimately, McKenzie shows that with foresight and global cooperation, difficult problems in science can be solved. As world leaders grasp for solutions to the climate change threat, this book suggests they might find a model in the Montreal Protocol.

Find more information on the book and the author on the Amazon webpage

This September the training team at EUMETSAT is going to kick off a series of online short courses that will cover weather, oceanography, air quality and climate.

The short courses are open to all interested participants and address a wide range of attendees, from service providers to young (and less young) scientists and forecasters.

More information about the online series and the course schedule is available on Moodle ^EXT, the EUMETSAT training platform at https://training.eumetsat.int/course/index.php?categoryid=97 ^EXT. Here participants can find information about the content and format of the sessions, and they can already register their interest ^EXT in the courses.

Each short course will offer a webinar with a presentation, a demonstration of data discovery and data application. Some courses will also include a follow-up self-paced phase where participants will have the opportunity to further explore the data and discuss it with experts.

YESS (the Young Earth System Scientists community) focuses on researchers working in the interdisciplinary field of Earth system sciences, including social and natural scientists.
Members within YESS cover a large breath of scientific expertise, including – but not limited to – weather, climate, geophysics, economy, engineering, hydrology, architecture, anthropology, governance, many more.

YESS members are organizing the webinar series on “Career Opportunities and Experiences in Climate and Weather Research for Latin America scientists”.

The first meeting will be on August 26th at 15UTC and 2 ECRs will give their testimonies.

Registration: https://eventos.redclara.net/event/1075/

The Climate Service Center Germany (GERICS), a scientific organizational entity of the Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, invites applications for a Scientific Coordinator to promote and help coordinate regional activities across the range of WCRP science (more about CORA). The office is shared between GERICS and the Bjerknes Centre in Bergen, Norway. To find out more, see the full position outline. The deadline for applications is 2 September 2020.