French National Committee for Geodesy and Geophysics (CNFGG) thesis prize in the Geophysics category awarded to :

Arthur Avenas, UMR LOPS, for his thesis entitled ‘Tropical cyclone dynamics revealed by satellite observations of surface wind speed: the major contribution of the surface wind structure near the core’, prepared at the École nationale supérieure Mines-Télécom Atlantique Bretagne Pays de Loire and defended on 28 March 2024.

‘Tropical cyclone dynamics revealed by satellite observations of surface wind speeds: the major contribution of the surface wind structure near the core’.

Despite advances in the prediction of tropical cyclone tracks and wind speeds in the outer region, the numerical representation of the strongest winds associated with the most intense events remains an open question, mainly due to the small size of the cyclone core and the difficulty in understanding and resolving the turbulent exchanges between the ocean and atmosphere. Observational limitations have long hampered accurate measurements of the ocean surface near the core region in extreme wind conditions, while geostationary satellites help characterise cloud patterns but do not provide direct information on the air-sea interface. Recently, synthetic aperture radar (SAR) has emerged as a promising satellite technology capable of producing high-resolution two-dimensional measurements of wind speeds at the ocean surface, thanks to new acquisition modes and algorithmic developments. Given these new observational opportunities, we are exploring the contribution of near-core structural features, only discernible through high-resolution instruments, to cyclone dynamics. Using a simple theoretical framework and examining its consistency with SAR measurements, we demonstrate that surface winds near the core control the evolution of the cyclone wind structure. The framework developed illustrates how future measurements of ocean-atmosphere boundary layer characteristics could benefit from short- and long-term monitoring of tropical cyclones.

In 2023, the IPCC deemed it highly unlikely that the AMOC would collapse by the end of the century. In a recent letter, some experts believe that this risk has been underestimated. What is this current? How does it influence the climate? Is its collapse imminent? What would be the consequences?

With

• Didier Swingedouw Climatologist at the Environnements et Paléoenvironnements Océaniques et Continentaux (EPOC) laboratory in Bordeaux.
• Pascale Lherminier Physicist at Ifremer, UMR LOPS in Brest.

View the broadcast here

Global warming is threatening a vast set of marine currents in the Atlantic Ocean: the AMOC. According to 43 international experts, we have underestimated the risks of shutting it down. What would be the consequences?

The AMOC is a system of ocean currents, of which the Gulf Stream is a part. It is one of the major drivers of climate, playing a crucial role in redistributing heat around the planet, and is one of the reasons why our climate in Western Europe is temperate. In a recent letter, experts stress the collateral effects of its slowing down, or even its collapse. Because this is now a probable risk.

On 18 November 2024, the annual Brest-Iroise Workshop Zone (ZABrI ) Day was held at the Institut Universitaire Européen de la Mer (IUEM) in Plouzané. Attended by 60 participants, the central theme of the event was co-construction between scientists and local stakeholders. The aim was to explore and strengthen collaboration to improve understanding and management of socio-ecosystems.

Enriching discussions on co-construction

The day began with an introduction and presentations of projects illustrating the diversity of multidisciplinary and transdisciplinary approaches. Participants were able to discover, among other things, the ETICS project on the development of innovative methods based on molecular biology for trophic ecology and the DYNARADE project, focusing on the shared management of coastal environments in the Brest harbour, with the example of the Spartina.
Three thematic sessions followed, offering a variety of perspectives on co-construction. The presentations highlighted the importance of close cooperation between researchers, local authorities, associations and other stakeholders in tackling environmental issues. Inspiring examples, highlighting, for example, the role of biosphere reserves in strengthening partnerships, participatory observation approaches, the involvement of local authorities in governance, the importance and methods of mediation in sharing knowledge and transforming practices, illustrated the diversity of projects and partnership dynamics carried out in the ZABrI and the other Workshop Zones.

Collaborative workshops to build the future

The second part of the afternoon was devoted to workshops. Divided into groups, the participants considered co-construction approaches in conjunction with different types of stakeholder: local authorities, civil society and natural environment managers. These discussions helped to identify levers for action to enhance collaboration and improve existing practices.

An action-oriented conclusion

At the end of the day, the workshops were summed up in a summary of the discussions and proposals, confirming the participants’ commitment to continuing this collaborative dynamic. Fred Jean, Director of the IUEM, brought the event to a close by stressing the importance of strengthening the links between science and territory in the face of environmental challenges.
The day’s events were a great success, providing food for thought on how to build close, lasting partnerships to serve socio-ecosystems. The cross-disciplinary approach adopted by ZABrI illustrates how research can be part of a collective approach to meeting local and global environmental challenges.

 

The IUEM Director and his team wish all the Institute’s staff and students an excellent year 2025!