Demain, le mix électrique français sera-t-il plus « vert » avec ou sans nucléaire ?

Source: The Conversation – in French – By Bertrand Cassoret, Maître de conférences en génie électrique, Université d’Artois

Au-delà de l’enjeu urgent de la transition énergétique, tous les mix électriques ne se valent pas en termes d’impacts environnementaux. Nous avons procédé à l’analyse de cycle de vie des six scénarios proposés par RTE à l’horizon 2060, avec ou sans construction de nouvelles centrales nucléaires. Le résultat ? Hors risque d’accident, les scénarios comportant le plus de nucléaire apparaissent comme les moins mauvais pour l’environnement.


Quel mix de production d’électricité décarbonée est le plus écologique ? Répondre à cette question n’est pas si évident. La production d’énergie, à l’échelle d’un pays, ne s’improvise pas : la troisième programmation pluriannuelle de l’énergie (PPE3), dévoilée en février 2026, a en ce sens fixé un cadre pour les dix prochaines années.

Or, en fonction des choix de planification opérés et du mix électrique retenu (part de nucléaire, de renouvelables…), le kilowatt-heure n’aura pas la même empreinte environnementale. En nous appuyant sur les six scénarios (en fonction des sources d’énergie composant le mix électrique) retenus par RTE à l’horizon 2060, nous avons mené une analyse de cycle de vie (ACV) de chacun de ces scénarios, récemment publiée dans une revue scientifique.

Selon nos résultats, en fonctionnement normal (c’est-à-dire en excluant les risques de catastrophe environnementale, notamment nucléaire), ce sont les scénarios où la part du nucléaire est la plus élevée qui ont les impacts environnementaux les plus faibles. Pour comprendre ce résultat, il faut d’abord présenter sa construction.

Les scénarios de RTE pour la production d’électricité en 2060

Ils sont le premier élément déterminant du raisonnement. Pour prévoir les besoins de production électrique en France en 2060, RTE a pris pour hypothèse une hausse de consommation de 35 %, en lien avec les besoins d’électrification des usages tels que les transports, le chauffage ou l’industrie.

Parmi les six scénarios, les trois premiers (notés M sur le graphe ci-dessous) n’utilisent pas de nouvelles infrastructures nucléaires en remplacement des réacteurs actuels qui seront probablement fermés en 2060. Les trois scénarios suivants (notés N) s’appuient en revanche sur le « nouveau nucléaire », avec une part de nucléaire allant de 18 à 50 % dans le mix électrique. La part de l’hydroélectricité varie peu, mais l’éolien et le photovoltaïque jouent le rôle de variable d’ajustement entre les différents scénarios.

Sur les six scénarios envisagés par RTE à l’horizon 2060, les trois premiers, notés M, ne postulent pas la construction de nouvelles centrales nucléaires pour remplacer les infrastructures actuelles, qui seront en fin de vie. Les trois derniers, notés N, postulent au contraire le renouvellement du parc nucléaire.
Fourni par l’auteur

Pour un même niveau de consommation électrique, les scénarios sans nucléaire nécessitent davantage de puissance installée. Le scénario M1, qui s’appuie le plus sur le photovoltaïque, requiert plus de deux fois plus d’installations que le scénario N03, qui se base surtout sur le nucléaire. Ceci s’explique par deux raisons.

  • D’abord, parce que l’éolien et le photovoltaïque ne sont pas pilotables : leur production dépend de la météo. L’éolien et le photovoltaïque ont, en effet, un facteur de charge assez faible : le vent et le soleil ne permettent que rarement une production à pleine puissance. Par exemple, une installation photovoltaïque de 1 000 watts (W) va produire parfois cette puissance l’été, vers midi, mais en moyenne sur l’année, seulement environ 150 W. Il faut donc démultiplier les moyens.

  • La seconde raison tient au besoin de stockage de cette production intermittente, afin de répondre aux besoins au bon moment. La prospective de RTE considère le stockage par batteries ou par hydrogène, mais les rendements de conversion entraînent, dans les deux cas, des pertes qu’il faut compenser, là aussi en augmentant les capacités installées.

À noter enfin que la fabrication et le recyclage en fin de vie de ces moyens de stockage entraînent des impacts environnementaux supplémentaires.




À lire aussi :
Les panneaux solaires, fer de lance de la transition ou casse-tête pour le recyclage ? Le vrai du faux


Des impacts environnementaux tout au long du cycle de vie

Les moyens de production envisagés par RTE ici sont l’éolien, le photovoltaïque, l’hydroélectrique et le nucléaire. Ils n’émettent pas – ou très peu – de polluants et de gaz à effet de serre lors de leur utilisation, comme en atteste le dernier rapport du Groupe d’experts intergouvernemental sur l’évolution du climat (Giec). Ce dernier considère que l’éolien et le nucléaire émettent environ 12 g de CO₂ par kilowattheure (kWh) électrique produit, tandis que le photovoltaïque en émet entre 41 et 48.

Mais la seule comptabilité carbone ne suffit pas : ces sources d’électricité ont des impacts environnementaux notables liés à leur fabrication et leur fin de vie, dont il faut tenir compte. Des études suggèrent que le photovoltaïque au sol (à distinguer des panneaux solaires qui équipent les toitures) peut nécessiter autant de béton que le nucléaire, à production électrique égale. L’Agence internationale de l’énergie (AIE) soulignait par exemple, en 2022, que les panneaux solaires sont de grands consommateurs d’aluminium. Enfin, toujours à production d’électricité égale, il faut davantage d’acier pour l’électricité éolienne que le nucléaire.

Une synthèse d’études d’impacts réalisée en 2021 pour la Commission européenne suggère que l’énergie nucléaire est celle qui aurait le moins d’impacts environnementaux sur un certain nombre de critères.

Il faut enfin tenir compte de la durée de vie des moyens de production. On considère généralement qu’un barrage hydroélectrique dure quatre-vingts ans, une centrale nucléaire soixante ans (même s’il est probable qu’on ira au-delà), un panneau photovoltaïque trente ans et une éolienne vingt-cinq ans.

Reste aussi la question des déchets nucléaires, qui relève, en France, de l’agence nationale pour la gestion des déchets radioactifs (Andra), et que nous n’avons pas couverte dans notre étude.

Quel scénario est le plus écologique ?

L’analyse de cycle de vie est une méthode qui permet d’évaluer les impacts environnementaux depuis l’extraction des matières premières jusqu’à la fin de vie. Elle utilise des bases de données internationales qui permettent de quantifier les consommations de matières premières, énergie, surfaces, déchets. Nous avons utilisé, pour estimer l’impact environnemental de la production d’un kilowattheure d’électricité nucléaire, hydroélectrique, éolienne et enfin photovoltaïque, le logiciel Simapro, associé à la base de données Ecoinvent qui fait référence dans le domaine de l’ACV

Parmi les 11 critères retenus, on retrouve l’épuisement des ressources, le réchauffement climatique, la diminution de la couche d’ozone, la toxicité pour l’humain, les impacts sur l’eau de mer et l’eau douce, l’oxydation photochimique (en lien avec la pollution de l’air), l’acidification et l’eutrophisation des eaux.

Selon notre ACV, le photovoltaïque est l’énergie qui a le plus d’impacts environnementaux et l’hydroélectrique, celle qui en a le moins. Ces résultats sont largement liés aux quantités de matériaux utilisés et à la durée de vie des installations.

La prise en compte de certains de ces critères environnementaux spécifiques peut modifier ce classement : le nucléaire a davantage d’impacts si on considère les radiations ionisantes et l’eutrophisation marine, l’hydroélectricité nécessite davantage d’eau. Mais même en tenant compte de davantage de critères environnementaux, avec la méthode ReCiPe, qui en comporte 22, le photovoltaïque reste le plus mauvais élève pour 18 de ces critères.

Impacts environnementaux d’une même quantité d’électricité, selon son mode de production.
Fourni par l’auteur

Les impacts des six scénarios de RTE ont été comparés avec deux approches différentes mais complémentaires.

  • D’abord en fonction de l’énergie produite par les quatre sources d’électricité chaque année. À noter qu’avec cette méthode, les impacts de la production du combustible nucléaire et de la gestion des déchets sont inclus dans les bases de données, mais que les moyens de stockage de l’électricité sont ici négligés, ce qui sous-estime les impacts des scénarios sans nucléaire.

  • Puis en fonction de la puissance installée, en tenant compte de la durée de vie des installations – en négligeant cette fois les impacts liés au fonctionnement normal des infrastructures. Les impacts du stockage sont, alors, pris en compte.

Les résultats obtenus avec les deux méthodes sont très similaires : le scénario M1, qui s’appuie le plus sur le photovoltaïque, est celui qui a le plus d’impacts environnementaux sur tous les critères considérés. Le scénario qui a le moins d’impacts, à l’inverse, est celui qui compte le plus sur le nucléaire. Même dans le scénario N2, qui compte largement sur le nucléaire, la majorité des impacts environnementaux proviennent du photovoltaïque, alors qu’il ne représente que 16 % du mix électrique.

Impacts environnementaux estimés pour les différents scénarios RTE.
Fourni par l’auteur

Il ne s’agit pas de dire que le photovoltaïque et l’éolien sont inutiles à la transition énergétique : ces sources renouvelables sont très utiles lorsqu’elles permettent d’éviter de produire de l’électricité avec du pétrole, du gaz ou du charbon. L’éolien et le photovoltaïque sont beaucoup moins polluants que ces énergies fossiles, qui n’ont pas été considérées ici.

Elles ont bien un rôle à jouer : RTE estime que le nucléaire et l’hydroélectricité ne permettront pas de produire suffisamment d’électricité pour l’électrification prévue dans le cadre de la Stratégie nationale bas carbone (SNBC). De plus, les technologies évoluent, et il est probable que les impacts du photovoltaïque et de l’éolien diminuent avec le temps.

À l’heure de choisir un mix électrique pour l’avenir qui s’appuie le moins possible sur les énergies fossiles, le nucléaire semble donc incontournable pour un mix le plus vert possible. Ces résultats montrent que plus la part du nucléaire est élevée dans le mix électrique, moins on a besoin d’installations en tous genres – consommateurs de matériaux –, moins on crée d’impacts environnementaux.

Notre étude a toutefois des limites, qui tiennent à ses hypothèses de départ : elle ne prend pas en compte le risque de catastrophe nucléaire. En effet, l’ACV ne considère que le fonctionnement normal des installations, et sa précision dépend de la fiabilité des données inscrites dans les bases de données.

Elle n’intègre pas non plus ni le risque d’explosion d’hydrogène stocké ni le risque de ruptures de barrages hydrauliques qui ont pourtant historiquement tué bien plus que les catastrophes de Tchernobyl et de Fukushima. Il est également supposé que la gestion des déchets nucléaires sera sans conséquences sur les générations futures.

The Conversation

Bertrand Cassoret est membre bénévole de l’Association Française pour l’Information Scientifique et de la Société Française d’Energie Nucléaire.

– ref. Demain, le mix électrique français sera-t-il plus « vert » avec ou sans nucléaire ? – https://theconversation.com/demain-le-mix-electrique-francais-sera-t-il-plus-vert-avec-ou-sans-nucleaire-277288

How biological invasions are silently remodelling ecosystems

Source: The Conversation – France – By Franck Courchamp, Directeur de recherche CNRS, Université Paris-Saclay

Many of the most damaging invasions do not simply subtract species; they fundamentally remodel the environment, altering habitats, rewiring interactions, and shifting processes in ways that species lists alone cannot reveal.

Consider the goat, the horse or the deer, introduced to many islands around the world. While their voracious grazing can indeed drive native flora towards local extinction, the legacy is etched deeper into the land.

These invasive herbivores compact the earth, accelerate erosion, open up the undergrowth and modify fire regimes, scarring the landscape long after the herds are gone. These systemic changes threaten biodiversity just as profoundly as the loss of any single species.

To navigate this complexity, invasion scientists have increasingly turned to the Environmental Impact Classification for Alien Taxa (EICAT). This pioneering framework marked a significant leap forward, offering a transparent, evidence-based method to rank “invaders” by the severity of their toll on native species, from negligible effects to local extinctions.

However, EICAT operates with a specific blind spot: it is strictly species-orientated. It assigns a single global severity score to an invader, usually based on the worst-case scenario recorded in its invasive ranges. While powerful for global prioritisation, this approach can overlook the complexities in specific, local ecosystems, each with unique vulnerabilities. As a recent study published in PLOS biology illustrates, there is cause for further investigation.

The invisible architecture of invasions

In addition, biological invasions generate a spectrum of impacts extending far beyond direct effects on native species seen in typical assessments. In our recent synthesis published in 2025, we catalogued 19 distinct types of environmental impacts.

When examining all of the well-documented impacts, it became obvious that most structural changes operate at the level of communities, ecosystems or physical processes.

Crucially, twelve of these categories concern scales broader than the actual species: nutrient cycling, habitat structure, or the physical properties of soil and water, for instance whose impacts are therefore underestimated.

Three distinctive levels of structural changes can be distinguished:

Nutria are a species renown for its ecosystem engineering skills.
Max Saeling

Despite being widespread and well documented, these structural changes remain largely unclassified by frameworks that focus ultimately on native species loss.

This omission is critical because many invasive species act as “ecosystem engineers”, organisms that do not merely live in an environment but actively modify it, influencing the fate of entire communities.

To capture this nuance, from our recent research we developed a complementary assessment tool: EEICAT, the Extended Environmental Impact Classification for Alien Taxa.

From the invader to the invasion

EEICAT is not a replacement but an evolution. It brings a necessary expansion in impact assessments, while seeking simplicity and integration. It is based on EICAT, but it shifts the unit of assessment from the invasive species to the invasion event. Under this framework, all 19 impact types can now be considered and an invasive population can be assigned one or multiple severity categories, at any ecological level. Under EEICAT, the loose threads of evidence from multiple impacts can now be woven to reflect the unique tapestry of effects on native species, communities, processes, and even abiotic conditions.

The necessity of this distinction is vivid in aquatic systems invaded by zebra mussels (Dreissena spp.). In too many lakes, these molluscs threaten native mussel populations through competition and biofouling, a classic impact well captured by standard assessments. Yet, simultaneously, they are transforming the environment itself: filtering water, lowering turbidity, altering nutrient cycles, and triggering cascading shifts in vegetation and food webs. EEICAT allows us to map both the direct blow to native biodiversity and the systemic reengineering of the lake, within a single framework.

Zebra mussels (Dreissena polymorpha) attached to native mussels.

A similar logic applies to the terrestrial realm. The Argentine ant (Linepithema humile) is notorious for displacing native ants, simplifying communities into ghost towns, devoid of the usually numerous native ant species. But its influence ripples further. By disrupting mutualisms between plants and insects, these invaders alter seed dispersal, pollination, invertebrate assemblages, and even soil processes. These indirect, community-level impacts often differ in severity across invasion events, depending on climate, habitat integrity and recipient ecosystems. You can therefore assess several impacts per invasion, and characterise the specificities of each invasion: with a case-based approach.

invasive ant supercolony or ants tending aphids.
Alexander Wild (reuse prohibited without authorisation)

Context is everything

The plant kingdom offers some of the clearest arguments for an event-based approach. Acacia species, introduced globally, act as ecological chameleons. In South Africa, they are aggressive suppressors of native flora, or “fynbos”, and transformers of soil chemistry through nitrogen enrichment.

In Mediterranean Europe, the same Acacia dealbata species, commonly known as mimosa, may exert moderate competitive pressure but still alter fire regimes, litter accumulation and hydrology.

EEICAT provides a straightforward way to document these contrasts, where all evidence counts in helping to assess the severity of each particular invasion.

Reinterpreting the ecological history of biological invasions

Importantly, adopting EEICAT does not mean starting from scratch. We can leverage decades of existing impact studies, and even previous EICAT impact assessments could be adapted. The framework simply translates qualitative ecological evidence into a broader set of categories that span biological, community, and abiotic levels. It even uses the same five levels of severity, from “minimal concern” to “massive concern”, with the same guiding decision rules. This compatibility allows us to reinterpret the history of invasion ecology through a wider lens.

Because EEICAT is case-specific, it enables us to track how a single species behaves differently across regions, or how multiple invaders compound pressure on a single ecosystem. It reveals patterns of cumulative stress and ecosystem vulnerability that global scores simply cannot articulate.

Biological invasions are not merely about losing species; they are also about the silent rewriting of ecosystems. From the chemistry of the soil to the rhythms of wildfires, their impacts ripple through the environment long after their arrival. By embracing the Extended EICAT framework, we can finally capture the full scope of how invasive species really impact ecosystems, and tailor management strategies to the complex realities of the living world, with each invasion, one by one.


Created in 2007 to help accelerate and share scientific knowledge on key societal issues, the Axa Research Fund – now part of the Axa Foundation for Human Progress – has supported over 700 projects around the world with researchers from 38 countries on key environmental, health & socioeconomic risks, like this project led by Franck Courchamp. To learn more, visit the website of the AXA Research Fund or follow @ AXAResearchFund on LinkedIn.

The Conversation

Franck Courchamp received funding from The AXA Research Fund.

Laís Carneiro received funding from AXA Research Fund.

– ref. How biological invasions are silently remodelling ecosystems – https://theconversation.com/how-biological-invasions-are-silently-remodelling-ecosystems-277703

China’s new tariff-free regime for Africa: the potential upside and downside

Source: The Conversation – Africa – By Lauren Johnston, Associate Professor, China Studies Centre, University of Sydney

China’s President Xi Jinping announced in February 2026 that from 1 May China would be granting zero-tariff treatment to 53 African countries. (That is all of them bar Eswatini, which supports Taiwan.)

China-Africa trade reached US$348 billion in 2025, up 17.7% from 2024. Chinese exports to Africa dominate trade flows, and amounted to US$225 billion, an increase of 25.8%. This compares to US$123 billion in imports from Africa, which grew by just 5.4%. Such a rising trade deficit between Africa and its largest sovereign trade partner points to the timeliness of new China policies that support African exports to China.

Beyond potential for trade facilitation and diplomacy, at a time of trade rivalry between the great powers, what might the change mean?

Based on years of study of China-Africa trade relations, I argue that there will be two probable main effects – one positive, one negative.

First, on the positive side, zero tariffs could provide incentives for cross-country export cooperation within Africa. On the negative, it risks creating conditions in which Africa’s stronger economies capture the most gain at the expense of weaker economies.

The existing regime

China’s Africa-specific trade preferences have evolved through the Forum on China-Africa Cooperation, established in 2000. China’s own global trade integration since its accession to the World Trade Organization in 2001 has also evolved.

Since 2005, African least developed countries have enjoyed zero-tariff access to China across 100% of tariff lines. Least developed countries are low-income countries confronting severe structural impediments to sustainable development. They are highly vulnerable to economic and environmental shocks and have low levels of human capital.

This policy restricted zero-tariff trade access to around 33 countries (subject to change owing to income growth and diplomatic recognition of Beijing). Africa’s middle-income exporters were excluded from the trade preferences.

South Africa, for example, continued to face tariffs on most exports, including fruits, wine and processed foods. Many were between 10% and 25%.

A handful of research papers have explored earlier Chinese trade preferences for Africa. For example, policy researcher and economist Adam Minson estimated that the least developed country tariff-free arrangements of 2005 would bring some countries as little as an additional US$100,000 annually.

My own PhD research found that by 2009 these preferential trade policies had not had any significant impact on exports. More recently, economists Zhina Sun and Ehizuelen Michael Mitchell Omoruyi found that the existing zero-tariff policy had promoted diversification of manufacturing exports to China and of regional trade. But there had been little effect on agriculture and mining export diversification.

One recurring recommendation has been to expand equal tariff treatment across African regional blocs. These include the East African Community, Southern African Customs Union and the Economic Community of West African States.

This could lead to production for export being organised regionally rather than distorted or even hampered by tariff differentials.

The reforms announced by Xi in February are a shift in this direction.

An incentive to co-operate?

By extending zero tariffs to almost all African countries, China has neutralised an element of distortion in its earlier tariff policy. When only some countries enjoyed tariff-free export benefits, investors and producers had incentives to locate export production in least developed countries to secure tariff-free access.

This worked some of the time, but not all the time. The reason for this is that least developed countries find it difficult to become exporters because they face inhibiting barriers to trade in general. Examples include unreliable electricity and poor infrastructure.

The zero tariff will put least developed countries at a disadvantage as they will lose the “special status” afforded them in the old regime. But the change could open another door. Production decisions can now take advantage of existing and potential cross-country and intra-regional supply chains based on comparative advantage – in place of being located where export tariffs were smallest.

Also, lowering tariffs for more developed African economies may enable African entrepreneurs to work across borders to engage in trade without facing different trade barriers by locality. That in turn may support Africa’s own agenda of trade integration.

To boost trade, China has also signalled it will expand trade facilitation measures. This includes upgraded “green lanes” for African imports. Prospective examples include:

  • faster customs clearance

  • streamlined phytosanitary procedures (rules governing food safety). An example would be setting up a clear set of criteria that enable an approved exporter, say of Kenyan avocados, to enjoy pre-approval for customs clearance.

  • greater investments in training and trade-related logistics.

China has also set up a dedicated China-Africa trade facilitation hub in Changsha, the capital of Hunan province. The aim is to have a central point of trade-related expertise and industries, making it easier for African and Chinese firms do business.

The risk of uneven gains

There is a risk that the new tariff regime will mean that production for export will concentrate in more developed countries, such as South Africa, Morocco and Kenya. These economies are better positioned to expand exports when it comes into effect.

In contrast, least developed countries will continue to struggle with:

  • constructing efficient trade-related infrastructure like telecommunications, electricity and port connectivity

  • production at export scale

  • reaching trade-related compliance standards such as the necessary fruit sizes and colour consistency.

China’s policy change calls for Africa’s frontier exporters to China to build trade-related supply chains across African borders to garner the scale and competitiveness to expand their own – soon tariff-free – exports to China. In turn, this would reduce the burden on least developed countries to need to export directly to China. Instead, they would only need to join regional trade supply chains.

Ideally within African sub-regions this could develop into a new incentive to create trade-related value chains.

The potential for equalisation

The May Day tariff reforms are a positive in removing formal tariff barriers at a time when tariffs are going up, led by the United States. This change simplifies incentives and eliminates structural asymmetries in China’s Africa trade regime.

Tariffs, however, are seldom the main constraint for African industrial transformation and export hopes. On top of this, uncertainty is complicating the global trade environment.

Nonetheless, these reforms are a step towards fostering sub-regional supply chains if African countries coordinate production strategies.

The Conversation

Lauren Johnston is affiliated with the AustChina Institute and South African Institute of International Affairs.

– ref. China’s new tariff-free regime for Africa: the potential upside and downside – https://theconversation.com/chinas-new-tariff-free-regime-for-africa-the-potential-upside-and-downside-277247

Cracking the code: How a “prediction machine” is resurrecting the Singapore Stone

Source: The Conversation – Indonesia – By Francesco Perono Cacciafoco, Associate Professor in Linguistics, Xi’an Jiaotong-Liverpool University

Singapore Stone wikipedia.org, CC BY

Several years ago, my linguistic research team and I began developing a computational tool we call ‘Read-y Grammarian’. Our goal was to reconstruct the highly fragmentary text of the Singapore Stone, a relic from the 10th to 14th centuries that features an undeciphered script similar to Kawi.

The software uses a specialised algorithm that applies digital philology (the study of oral and written texts) and epigraphy (the study of written matter recorded on hard or durable material) techniques to analyse ancient inscriptions.

We faced several setbacks while developing ‘Read-y Grammarian’ over the years. However, thanks to our persistence, the system is finally complete and fully operational.

Originally implemented for the Singapore Stone, ‘Read-y Grammarian’ can be used to reconstruct any fragmentary text. Its adaptive framework allows it to restore a wide array of damaged historical records — including manuscripts and papyri — with a few simple adjustments.

This flexibility makes the tool a powerful new ally for researchers looking to piece together the missing fragments of human history.




Baca juga:
The Singapore Stone’s carvings have been undeciphered for centuries – now we’re trying to crack the puzzle


About the Stone

First recorded by the British in 1819 at the Singapore River’s mouth, the sandstone monolith was later demolished in 1843 to clear space for building projects. The roughly three-metre-square slab was largely destroyed, leaving only three surviving fragments.

After researchers sent those fragments to the Royal Asiatic Society’s Museum in Calcutta for study, their trail went cold. Their fate remained undocumented for decades until 1918, when — as far as records show — the institution returned only a single piece to what was then the Raffles Museum of Singapore.

Drawings of the fragments of the Singapore Stone
Singapore Stone’s fragments.
https://www.mdpi.com/journal/histories, CC BY

The Stone originally bore an inscription spanning roughly 50 lines, but its full text has been lost. All that remains are a handful of rough sketches made before its destruction, along with copies of the three fragments recovered after 1843 and the single original fragment that still exists.

The inscription remains a major puzzle. Its script resembles regional writing systems like the Javanese Kawi, but actually it doesn’t match any known writing system found on Earth.

Because no one has been able to read the Stone yet, it remains undeciphered.

The monument’s turbulent history, coupled with the complex and unique nature of its script, has fuelled its myth over the centuries. This has turned the artefact into one of the most intriguing challenges for scholars.

Alongside legendary puzzles like the Phaistos Disc and Linear A, the Singapore Stone remains one of History’s great unsolved codes.

Some link it to the legendary strongman Badang and the sprawling Majapahit Empire. Yet, until the conundrum is cracked, all connections — including those with ancient India or Java’s influence — remain speculative.

Decoding the void

Among other computational methods, ‘Read-y Grammarian’ works by digitising the inscription and assigning a unique alphanumeric (composed of both letters and numerals) code to every attested character. By tracking the exact position and line of every symbol, the algorithm identifies gaps in the text and reconstructs the likely original layout line by line.

It then applies frequency analysis and statistical and mathematical calculations — based on the linguistic patterns found in human languages — to predict which characters may have filled the missing spaces. This way, ‘Read-y Grammarian’ acts like a ‘prediction machine’, analysing the text step by step and converting its alphanumeric outputs back into actual characters.

We can also adjust specific settings in the system. For example, we can tweak the syntax (grammar rules and word order) of a reference language or language family — such asJavanese or Austronesian — or adjust the related morphology (the internal structure of words and how they are formed).

The algorithm then generates different possible versions of the text and our research team reviews these versions to determine which ones make the most sense linguistically.

This approach allows us to map phonemes (distinct units of sound that distinguish one word from another) to every character in the text, helping us identify possible words. It significantly streamlines the comparative process, letting scholars test the script against a variety of candidate languages to find a possible match.

Sample of the restoration of two Singapore Stone's characters
An example of Singapore Stone’s character restoration.
https://www.mdpi.com/journal/information, CC BY

What we know so far

Our ultimate goal is to solve the mystery of the elusive inscription. A text can be considered truly deciphered only when it can be read and understood in full.

Identifying an exact language will take time. However, we have already reached an important breakthrough: after centuries of silence, we have reconstructed several plausible versions of a complete text. This is a significant achievement, because the monolith itself was almost entirely destroyed. Reconstructing the original inscription would have been impossible without our custom algorithm.

Moreover, we are currently developing a more sophisticated model to expand the capabilities of ‘Read-y Grammarian’. The upgrade will allow us to generate systematic transcriptions at a much faster rate and in greater numbers. It will also incorporate advanced features, such as elements of historical phonology (the study of how sound systems change and evolve over time), to further refine the results.

A work in progress

Deciphering the Singapore Stone has proven extremely difficult, primarily because so little of the inscription survives. The fragments are too small to support reliable frequency analysis — assessing how often specific symbols appear in a text — or statistical studies.

Yet, pattern-recognition methods are the core tools of cryptanalysis (the art of cracking codes and ciphers), and they require far more data than the highly damaged epigraph can currently provide.

To break the deadlock, we must first focus on consistently reconstructing the full inscription. By restoring the text piece by piece and line by line, we can finally view the result as a complete composition.

Though this is not the same as actually reading the inscription, rebuilding the Stone’s original contents gives us the foundation we need to analyse the structure of its text.

Before we can interpret and decipher its fragmentary remains, this crucial first step will pave the way for decoding its writing system and finally identifying the unknown language hidden within.

The Conversation

Francesco Perono Cacciafoco received funding from Xi’an Jiaotong-Liverpool University (XJTLU): SURF Grant “Unveiling the Secrets of the Singapore Stone: A Digital Philology Investigation” – Grant Number: SURF-2025-0032, School of Humanities and Social Sciences (HSS), Xi’an Jiaotong-Liverpool University (XJTLU), Suzhou (Jiangsu), China, 2025.

– ref. Cracking the code: How a “prediction machine” is resurrecting the Singapore Stone – https://theconversation.com/cracking-the-code-how-a-prediction-machine-is-resurrecting-the-singapore-stone-276642

Mandelson files released at sensitive time for UK relations with Donald Trump

Source: The Conversation – UK – By Christopher Featherstone, Associate Lecturer, Department of Politics, University of York

The release of the “Mandelson files” comes at a difficult moment in relations between the US and UK. It is unlikely to ease tensions.

The UK government has submitted to pressure from MPs to disclose files relating to the hiring and vetting of Peter Mandelson as UK ambassador to the US. Questions have been raised about how much officials, including the prime minister, Keir Starmer, knew about Mandelson’s friendship with paedophile Jeffrey Epstein after his conviction for sex offences in 2008.

The key takeaway from the release doesn’t relate to the US president, Donald Trump. This is that Mandelson tried to negotiate a severance package worth £547,201 after being asked to leave his post in Washington. He ended up getting £75,000. But there are details in the documents that will not be welcomed by the US, and the nature of the release will be of concern to a White House already under pressure for its own approach to Epstein.

Trump has already spent recent weeks publicly criticising Starmer for failing to support him on Iran, saying Starmer is no “Winston Churchill”. The release of these files may well lend further opportunity for Trump to hit out.

Lack of control

The questions about how much Starmer knew about Mandelson and Epstein arose in the first place after the US government partially released the Epstein files in January. These included email exchanges between Mandelson and Epstein revealing a relationship that extended long after the latter’s conviction. They have also led to a police investigation over communications made between the two men while Mandelson was a government minister. These allegedly relate to sensitive government information rather than anything relating sex offences.

Trump will not like the fact that this release has brought the Epstein files back into the spotlight – and particularly that it is happening in circumstances beyond his control.

Trump has repeatedly called for the Department of Justice to “move on” from this story, having faced questions about his own relationship with Epstein. He recently attacked CNN journalist Kaitlan Collins for not smiling as she asked him questions about the Epstein files, in a clear attempt to distract public attention.

There is a risk that the Mandelson document release will renew pressure on Trump to release the full cache of documents held by the US government – and that he will seek to divert attention by lashing out again at Starmer.

Donald Trump and Keir Starmer talking.
Trump and Starmer, pictured in September 2025.
Number 10/Flickr, CC BY

Unsurprisingly, given that many of these released documents were written for private consumption, they contain some comments that may be embarrassing for the authors and subjects.

In the documents, we can see the UK government reviewed public comments Mandelson made condemning Trump policies prior to his appointment as ambassador, apparently to consider whether they were a problem during the vetting process.

When speaking to students in Hong Kong, Mandelson said: “it’s also necessary to recognise Mr Trump’s behaviour for what it is: he is a bully and mercantilist who thinks that the US will gain in trade only when others are losing”. Trump will likely be annoyed by this attack on his treasured “tariffs” policy.

Crucially, given that Starmer appointed Mandelson despite these comments, these documents also show that the UK government did not object to Mandelson’s view.

London v Washington

The release from the UK will fuel a debate that has begun on the difference between how London and Washington have both responded to the the revelations in the Epstein files. The Trump administration continues to refuse to release its own files in full – and continues to be accused of covering up Trump’s relationship with Epstein.

The UK government has demonstrated that it is willing to fire people over their relationships with Epstein and that it won’t protect them from police investigation. Now it has shown willingness to release files showing how much the government knew about these relations. This is of course not the full release of files and Starmer insists several key items can’t be released because they are part of an ongoing police investigation, but it still leaves space for criticism of the US.

Trump and his administration will have been hoping that media attention would move on, focusing on the controversial airstrikes on Iran, or continuing ICE raids across US cities. It will not welcome inevitable comparisons between its unwillingness to act on revelations from the Epstein files – or to keep releasing more files – and the UK government’s decision to do both.

Crucially, US government officials will be watching for further document releases to see if this situation gets any worse.

The Conversation

Christopher Featherstone does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. Mandelson files released at sensitive time for UK relations with Donald Trump – https://theconversation.com/mandelson-files-released-at-sensitive-time-for-uk-relations-with-donald-trump-278129

Black female footballers are praised for their strength, white players for their intelligence: what our study shows

Source: The Conversation – UK – By Paul Ian Campbell, Associate Professor in Sociology (Race and Inclusion in sport and in education), University of Leicester

Rawpixel.com/Shutterstock

For black female professional footballers, racism has become a distressingly regular part of the game. Earlier this year, England defender Jess Carter told the BBC that the racist abuse she received online during the 2025 Euros made her fearful to leave her hotel room.

Black sportswomen routinely deal with racial abuse from fans and teammates. But less discussed is how their bodies, emotions and on-pitch performances are spoken about by sports commentators. It’s not just negative comments, either. Clear racial stereotypes emerge when comparing positive comments about black players with those about white players. Our 2025 study examines commentary during the 2019 Fifa Women’s World Cup, does just that.

We analysed 2,905 comments of praise given to footballers during 80 hours of BBC and ITV coverage, across all 52 matches at the tournament. We found that white women were more frequently praised for their intelligence and technical proficiency, while black women received the most praise for their perceived physical prowess and natural athleticism.

White players were more frequently praised skills learned through practice, such as having a “lovely technique” (49.4% of all comments about white players), followed by physical (20.3%), character (16.2%), cognitive (10.8%) and natural (3.3%) abilities.

Black players received almost double the amount of praise for their physical prowess (39.5% of comments about black players) and natural abilities (5.8%). They received notably fewer praise comments for learned skills (36.8%), as well as lower amounts of praise for character (11.9%) and cognitive attributes (6.0%).

These differences were especially noticeable in the coverage of national teams from white-majority countries that had more than two black players in their starting squad. England’s two non-white players (accounting for 18.2% of the team) received 50% of all of their team’s praise for natural attributes. These were comments praising qualities that were perceived to be innate, such as being a “magician” on the pitch. England’s visibly white players (81.8% of the team) received almost the entire amount of the praise given to the whole team for cognitive attributes (96%).

Jess Carter discusses her experiences with racism.

France’s black players, who accounted for 43% of team, received 90% and 85% of the team’s total praise for natural and physical attributes, respectively. White French players, who similarly constituted 43% of the playing squad, received 68% of the teams’ total praise for intelligence.

We also found that black female players were more likely to be described as being angry and emotionally unstable during matches. Nigeria’s forward Desire Oparanozie was described as “playing with a bit of anger” and England’s Nikita Parris was said to be unable to maintain her composure, with a tendency to frequently “make her feelings known”.

Their white teammates, on the other hand, were described as calm and composed.
During the England v Cameroon match, commentators praised the almost entirely white England team for keeping their composure and not “reacting” to “unseemly things going on the pitch” by the African players.

The harm of misogynoir

Black women experience a unique form of discrimination called misogynoir. It is different to the exclusions faced by white women and the racism experienced by black men. It is the result of a combination of the misogyny directed at their gender and the anti-black racism directed at their race.

Sport media is a powerful site where the gender and racial stereotypes that exist in society are replicated. It has a long history of portraying black sportswomen as powerful, hyper-masculine and angry.

Studies have shown that black sportswomen are frequently stereotyped as unfeminine, masculine and strong, lacking intelligence, emotionally unstable, inherently angry and overly aggressive. Conversely, white women are seen to embody Eurocentric beauty standards and accepted feminine ideals, such as notions of purity, grace, emotional stoicism and delicacy.

These stereotypes have real-life consequences for black sportswomen. Some footballers have gone so far as to change how they play so that they are not seen as angry or masculine, but just as women who play the game they love. For example, ex-England player Anita Asante explained:

You have to check yourself to make sure people don’t view you in that light. Maybe on that particular day in a training session, I am that sassy person, or I am that competitive person that comes across a bit more feisty – but because there is an association with being a black woman and having that energy and boldness is not always seen a positive thing, [so] I might refrain from being that person and contain more of my emotions.

Evidence shows that misogynoir can influence the career opportunities that are afforded to black women more generally. A recent US study connected racism to higher levels of stress and to higher mortality rates.

Unless, meaningful action is taken by broadcasters to change the practice of commentary through tallying exercises like our research, then commentators might be unwittingly contributing to the racial stereotypes that cause psychological and physiological harm to the same superstars that they idolise and praise.

The Conversation

The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

– ref. Black female footballers are praised for their strength, white players for their intelligence: what our study shows – https://theconversation.com/black-female-footballers-are-praised-for-their-strength-white-players-for-their-intelligence-what-our-study-shows-276993

Congress still has ways to throttle back Trump’s war with Iran – and to ask questions

Source: The Conversation – USA – By SoRelle Wyckoff Gaynor, Assistant Professor of Public Policy and Politics, University of Virginia

What power does the U.S. Congress have over the president’s war in Iran? Douglas Rissing, iStock/Getty Images Plus

Despite the scale of its military assault on Iran, the Trump administration’s reasons for entering into war have been inconsistent and vague, from regime change to the destruction of nuclear weapons, preempting military action by Israel, or the more chilling decree of following “God’s divine plan.”

Politicians, pundits and even social media users have been quick to point out the contradictions of these justifications – regime change is impossible from the air, especially when you kill the alternatives, and weren’t those nuclear weapons already destroyed?

But the “why” for entering into war matters beyond scoring political points.

Why, and how, a president engages in military action has serious implications for the constitutional authority of any wartime action and, specifically, whether Congress has any hope of checking the warmaking of a president.

War powers and ‘imminent threats’

Under Article 1, Section 8, of the U.S. Constitution, only Congress has the authority to declare war.

One way around this, as the Trump administration and congressional Republicans have half-heartedly attempted, is to avoid calling this conflict a “war.” The messaging didn’t stick. In fact, President Donald Trump has already used the term repeatedly.

Secretary of State Marco Rubio asserted that the U.S. military action in Iran was prompted by an ‘imminent threat.’

The more viable option for sidestepping the need to have Congress declare a war is for the president to claim authority under the War Powers Resolution of 1973, which grants a president the power to involve the armed forced in “hostilities” or “potential hostilities” without congressional approval only under extraordinary conditions of “imminent threat.”

At least one member of the administration appears to understand this nuance: Secretary of State Marco Rubio – notably, a former member of Congress himself. Rubio used the specific terminology “imminent threat” when discussing why the Trump administration began the bombing.

Absent a truly imminent threat, the president is required by the resolution to “consult regularly” with Congress before and after engaging in military action. Importantly, the military action is limited to 60 days, during which the president must “report to the Congress periodically” with updates to keep the legislative branch informed.

After 60 days, the president must, the resolution says, “terminate any use of United States Armed Forces.” If a president wants to wage a war longer than that, that requires an additional declaration by Congress. Such a declaration would require votes similar to a bill being passed.

In 2002, for example, after initiating a “war on terror,” President George W. Bush eventually turned to Congress to pass the Authorization for the Use of Military Force Against Iraq. This permitted Bush to send troops into Iraq and further pursue a war that would last a decade.

In today’s case, by claiming that the Iranian regime was posing an imminent threat to the United States, the president can more easily circumvent congressional approval for military action and then turn to Congress after the fact if further action is needed.

As we recently discussed on our podcast about Congress, “Highway to Hill,” Congress has been continually ceding its power to the executive branch for decades. Deflection on military authority goes back even further: Congress hasn’t formally declared war since World War II – yes, despite involvement in Korea, Vietnam, Afghanistan and many other places. But the Constitution doesn’t mince words on who’s responsible for entering the U.S. into war: Congress.

And how this war is ultimately framed by the White House has implications for the types of oversight Congress can perform to limit or curtail military action.

The limited powers of the war powers resolution

Congress, seemingly caught off guard by the Trump administration’s actions in Iran, has responded in a few ways. Perhaps unsurprisingly, responses have fallen largely along party lines.

Following the initial bombings, U.S. Sen. Tim Kaine, a Democrat from Virginia, introduced a war powers resolution to prevent further military action in Iran. In the House, U.S. Reps. Ro Khanna, a California Democrat, and Thomas Massie, a Republican from Kentucky, introduced a similar bipartisan resolution. The votes failed in both chambers despite overwhelming support from Democrats.

On the Republican side, Rubio’s explanation for the military action seemed to appease many key members of Congress. Senate Majority Leader John Thune, a South Dakota Republican, claimed the president had the authority to move forward with military action in Iran.

Speaker of the House Mike Johnson, a Louisiana Republican, said that any congressional attempt to limit the president’s warmaking power would be “frightening” and “dangerous.”

Public accountability in congressional hearings

A large hearing room in a government building, with men lined up behind a long talbe in the front, and witnesses and the public on the other side.
Oversight at work in Congress, as the Senate Foreign Relations Committee on Feb. 10, 1966, holds one of its many hearings on the Vietnam war. George Kennan, former ambassador to Moscow, is at the witness table.
Henry Griffin, AP file photo

But Congress has two more traditional and frequently used oversight tools at its disposal: oversight hearings and the power of the purse.

Oversight hearings provide members of Congress an opportunity to not only question and investigate the executive branch’s activity, but also to provide their constituents with this fact-finding work and draw attention to policy issues. As some recent oversight hearings indicate, these can also be opportunities for partisan jabs and “made for TV” moments.

But there is evidence that they produce results.

Following tense oversight hearings on excessive spending in the Department of Homeland Security, Secretary Kristi Noem was fired from her position in early March 2026.

In the 1970s, the Church Committee – named for its formidable chair, U.S. Sen. Frank Church of Idaho – held extensive hearings that included eye-opening testimony about clandestine U.S. intelligence activities abroad and domestically. The Church Committee recommended, and Congress subsequently enacted, dozens of sweeping reforms to foreign intelligence collection activities, as well as restraints on future efforts by the U.S. government to assassinate people.

Although the Trump administration has provided closed-door briefings to members of Congress, Democratic senators are asking for more. They are calling for Department of Defense Secretary Pete Hegseth and Secretary of State Rubio to come before congressional committees to explain their reasoning and plans for the Iran war.

Not only do oversight hearings provide members of Congress with an opportunity to investigate and question an administration’s actions, but they bring that discussion to the public. This transparency provides constituents with information about how their tax dollars are being spent, what their members of Congress think, and may even sway public opinion.

Power of the purse

But perhaps the most powerful tool that Congress has is its power of the purse, outlined in Article 1 of the Constitution.

Military actions in Iran are already costing an estimated US$1 billion a day, or as U.S. Rep. Tom Cole of Oklahoma, the Republican House Appropriations Committee chair, put it: “a lot.”

As the war drags on, the Trump administration will need more money – money that only Congress can dole out. Unlike war powers resolutions, which in this case would limit military action after the fact, new spending cannot occur until Congress writes and passes legislation appropriating additional funds.

But this would constitute a blank check for a foreign war. And that might be too much to ask of members of Congress in both parties, particularly as the U.S. faces a historic deficit and cuts to safety net programs.

And as public opinion on both military action in Iran and the state of the economy continues to sour, a vote for more military spending might well overtax any remaining goodwill of voters and members of Congress alike.

In fact, the political pressure on Congress to put its foot down could become so immense that lawmakers may have to do something – like their job.

The Conversation

The authors do not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

– ref. Congress still has ways to throttle back Trump’s war with Iran – and to ask questions – https://theconversation.com/congress-still-has-ways-to-throttle-back-trumps-war-with-iran-and-to-ask-questions-277813

How we turned plastic waste into vinegar: A sunlight-powered breakthrough

Source: The Conversation – Canada – By Yimin Wu, Associate Professor, Tang Family Chair in New Energy Materials and Sustainability, University of Waterloo

Hundreds of millions of tonnes of plastic are produced globally every year. New research shows how that waste can be turned into something useful. (Unsplash/Nick Fewings)

Plastic is one of the most durable materials humans have ever made. That durability has made it indispensable in medicine, food packaging and transport. But it’s also created one of the defining environmental problems we have faced.

Hundreds of millions of tonnes of plastic are produced globally every year. Much of it ends up in landfills, incinerators or the natural environment, where it can persist for centuries.

The methods we have for getting rid of plastic pollution have their downsides. Putting it in landfills means chemicals and microplastics can seep into the surrounding environment.

Burning it releases harmful fumes and toxins. Mechanical recycling often downgrades plastics into lower-value products, while chemical recycling typically requires high temperatures, high pressures and large amounts of energy.

Colleagues and I recently published research that explores a very different possibility: using sunlight and an iron-based catalyst to convert common plastic waste directly into acetic acid — the key component of vinegar and an important industrial chemical.

Instead of treating plastic purely as waste, our research shows that it can be transformed into something useful under mild conditions.

Learning from a wood-rotting fungus

The inspiration for our research came from nature. The white-rot fungus (Phanerochaete chrysosporium) is famous for its ability to break down lignin, one of the toughest polymers found in wood. It does this using enzymes that generate highly reactive chemical species capable of dismantling complex carbon structures.

We wondered whether a synthetic material could mimic this strategy.

The catalyst we designed is iron-doped carbon nitride, a semiconductor that absorbs visible light. We then anchored individual iron atoms, creating what scientists call a single-atom catalyst.

Rather than forming nanoparticles, each iron atom is isolated and embedded within the carbon nitride structure. This atomic precision is crucial. Each iron atom behaves like an active site in a natural enzyme, maximizing efficiency while maintaining stability.

A two-step reaction powered by light

The system works through a cascade of light-driven reactions.

Under sunlight and in the presence of hydrogen peroxide, the iron sites activate the peroxide to generate highly reactive hydroxyl radicals. A radical is an atom, molecule or ion that has at least one unpaired electron. This makes them highly chemically reactive.

These radicals attack the long carbon chains that make up plastics, like polyethylene (used in plastic bags), polypropylene (food containers), PET (drink bottles) and even PVC (pipes and packaging).

The polymers are progressively oxidized and broken down into smaller molecules, eventually forming carbon dioxide (CO₂).

Rather than allowing this CO₂ to escape, the same catalyst then performs a second job: it uses sunlight to reduce the CO₂ into acetic acid. In other words, the carbon in plastic waste is first oxidized and then re-assembled into a new, valuable molecule.

Essentially, this approach breaks down plastic and converts the resulting carbon into a commodity chemical in a single system. This distinguishes it from most existing recycling technologies.

Why acetic acid?

Acetic acid is best known as the sour component of vinegar, but it is also a major industrial feedstock. It is used to produce adhesives, coatings, solvents, synthetic fibres and pharmaceuticals.

Global demand runs into the millions of tonnes each year, representing a multi-billion-dollar market.

Currently, most acetic acid is produced through an energy-intensive processes process called methanol carbonylation, whereby methanol is reacted with carbon monoxide at high temperatures.

Converting waste plastic into acetic acid offers a potential circular pathway: instead of extracting new carbon, we reuse carbon already present in discarded materials.

In our experiments, the system produced acetic acid at rates comparably favourable with other reported light-driven plastic conversion methods. When we enhanced light utilization inside the reactor, the production rate increased substantially.

Importantly, the reaction operated at room temperature and normal atmospheric pressure. That contrasts with many chemical recycling methods that require heating plastics to several hundred degrees Celsius.

Handling real-world plastic

Laboratory studies often focus on pure, single plastic types. But real waste streams are mixed and contaminated. We therefore tested different common plastics individually, as well as mixtures.

Our catalyst was able to convert several major commodity plastics. Interestingly, PVC showed particularly strong performance. We believe chlorine released during its breakdown may generate additional reactive radicals, accelerating degradation.

The iron atoms remained atomically dispersed after repeated use, indicating good stability. This matters because catalyst degradation or metal leaching can undermine both performance and environmental safety.

The system does rely on added hydrogen peroxide, which is consumed during the reaction. While hydrogen peroxide decomposes into water and oxygen and is considered relatively benign, future work will need to address how it can be supplied sustainably at scale.

From concept to practice

Scaling up any new chemical process presents challenges. Light penetration, reactor design and the variability of waste plastic feedstocks all affect efficiency. Additives in commercial plastics — such as stabilizers, pigments and plasticizers — can also influence reaction outcomes.

To explore feasibility, we conducted a preliminary techno-economic assessment. This is a way of analyzing the potential economic benefits of an industrial process or product.

While further optimization is required, our analysis suggests that coupling waste cleanup with the production of a valuable chemical could help offset costs — particularly when environmental benefits are taken into account.

More broadly, this work illustrates the power of single-atom catalysts and bio-inspired design. By mimicking the way enzymes control reactivity at precise metal centres, we can achieve complex chemical transformations under mild conditions using sunlight as the energy source.

Rethinking plastic’s life cycle

The problem of plastic pollution will not be solved by a single technology. Reducing unnecessary plastic use, improving product design and strengthening recycling systems are all essential.

Transforming plastic waste into useful chemicals offers a complementary strategy. It reframes plastic not only as an environmental burden but also as a carbon resource.

If we can harness sunlight to drive these transformations efficiently and at scale, yesterday’s discarded packaging could become tomorrow’s industrial feedstock.

The challenge now is to translate our laboratory advances into robust, scalable systems. If successful, it would mark a step toward a more circular economy — one where waste is not the end of the story, but the beginning of a new one.

The Conversation

Yimin Wu receives funding from Tang Family Chair in New Energy Materials and Sustainability, Natural Sciences and Engineering Research Council of Canada, the seed funding from the Water Institute (WI), Waterloo Institute for Nanotechnology (WIN) at the University of Waterloo.

– ref. How we turned plastic waste into vinegar: A sunlight-powered breakthrough – https://theconversation.com/how-we-turned-plastic-waste-into-vinegar-a-sunlight-powered-breakthrough-276735

The retail afterlife: How surplus goods find new value at ‘binz’ stores

Source: The Conversation – Canada – By Christopher Lo, Associate Professor, Psychology, University of Toronto; James Cook University

The front of the Star Binz liquidation store in Toronto. Merchandise at these stores comes from major retailers and online platforms, which are purchased through liquidation auctions and resold. (Chris Lo), CC BY

For $25, you might walk out with a drone. Or a blender. Or a box of something you won’t identify until you tear through the tape.

At “binz” stores, bargain hunters line up early on Saturdays to gain first access to piles of surplus goods dumped into waist-high bins. The merchandise comes from major retailers and online platforms, which are purchased through liquidation auctions and resold.

Binz stores are one highly visible edge of the booming recommerce and liquidation economy. The global recommerce market, which resells returned, refurbished and second-hand goods, is projected to generate more than US$200 billion annually.

Binz stores attract not only low-income shoppers but a broad cross-section drawn by the thrill of discovery and ultra-cheap goods. As the high cost-of-living strains household budgets in Canada, more consumers have traded down, seeking discounts and secondary markets.

Binz stores represent a layer of the secondary market that is equal parts bargain hunt and chaos. Liquidation marketplaces, off-price retailers and salvage wholesalers form a vast ecosystem beneath traditional retail designed to recover value from goods that cannot be sold at full price.

The afterlife of surplus

To understand binz stores, it helps to understand how surplus is created in the first place. They are the cumulative result of supply chain logistics, prediction error and the extraction of value in what might be called retail’s surplus afterlife.

Modern supply chains are one-way highways that move goods from global manufacturers to centralized hubs, then to retail outlets. They are optimized for speed and efficiency, but they are rarely designed to run in reverse.

“Most of the supply chains are designed for moving goods from manufacturer to the consumer. They are not designed for returning stuff,” says Murat Kristal, professor of operations management at the Schulich School of Business at York University.

Going forward, you might drop off a box of 15 at every store, he says. Now imagine going backwards, collecting unsold items, two here, three there, store by store, and then having to transport, sort and store them all in the warehouse while the fashion cycle changes.

Reversing the system multiplies the cost of the “last mile” of delivery — typically the most expensive part of distribution, explains Kristal. These final legs of distribution can account for about half of total shipping costs in some supply chains, according to industry analyses.

In many cases, it is cheaper to liquidate excess inventory in bulk than to reintegrate it backwards through primary distribution channels.

Forecasting the future

Retailers must predict the future, months in advance. A shirt on the shelf today may have been ordered a year ago, after yarns were sourced and factories booked in Southeast Asia.

Shipping full containers lowers per-unit costs, while producing smaller batches increases them. The economics of global manufacturing favours volume and planning production far in advance — a classic example of economies of scale where the cost of producing each individual item falls as the total number of units produced increases.

Companies must forecast how many units will sell in a market: how many small, medium and large, which colours and styles. If they predict 100 and sell 80, 20 remain. This forecasting is not optional “because you need to give a number to your manufacturer,” Kristal says.

Error is built into that bet. Retailers forecast based on past sales and trends. To avoid running out of stock, companies routinely overproduce or over-order to prevent empty shelves and lost sales. In fashion, between 10 and 40 per cent of garments made each year may go unsold. That buffer helps ensure availability but inevitably generates surplus inventory when demand fails to materialize.

Returning items to the warehouse is costly, and storing last season’s inventory makes little economic sense in industries driven by cycles. Liquidation often becomes the rational choice.

But the future is becoming harder to read. “It’s just that the unpredictability of the world we live in is increasing,” Kristal says.

American tariffs, inflation rates and fast-fashion cycles have made retail demand more difficult to forecast. When forecasts are wrong, the surplus moves downstream to third-party liquidators.

Deflating value

Surplus goods lose value over time, but that value rarely disappears entirely. Instead, it continues to be extracted as goods move further downstream from manufacturers to liquidation channels, and ultimately to bargain-hunting consumers.

“With some exceptions, virtually everything that gets manufactured in the world gets sold,” says Mark Cohen, former director of retail studies at Columbia Business School. “Everything has an economic value that gets deflated as merchandise is bought, or merchandise is unsold” at its intended price and venue.

In binz stores, this value decay is prominently visible. Each day has a flat rate for binned items, with prices dropping daily until restock day renews the cycle. In one store, a board game that once retailed for $70 might sell for $25 on restock day, $10 by midweek and $1 by week’s end.

Each change of hands reduces margin, but value can persist longer than assumed. “Eventually, even if it winds up in a junkyard or in a garbage dump, there are increasingly attempts to extract value by repurposing or extracting material,” says Cohen.

The thrill of the hunt

Bargain hunting is not purely economic. It also has a psychological dimension. Research suggests that searching for deals can trigger feelings of excitement and reward, making binz shopping similar to a game of treasure hunt.

When consumers perceive they’re getting a good deal, the brain’s reward circuitry — associated with dopamine and feelings of satisfaction — can become more active, helping explain the emotional appeal of bargains.

“Go as early as possible to get the best merchandise,” says Jonatas Beltrão, a Toronto painter. He first stumbled across a binz store while walking by and became curious about the large tables piled with goods.

Beltrão still laughs about his proudest purchase: a coffee maker that cost $85 on Amazon that he bought for $8.99. He goes every two weeks for the fun of finding brand-name items at a fraction of their original cost.

The uncertainty of what might appear in the binz, and the bragging rights of finding a trophy, help explain why some shoppers keep coming back and how goods continue circulating long past their intended retail life.

Variable rewards can heighten engagement and motivation, making activities from gaming to bargain hunting more compelling because each search might uncover something valuable.

“There’s a buyer for almost everything,” Cohen says.

In that sense, binz stores show the afterlife of surplus goods: leftover merchandise becomes part of a shopping experience built around chance, discovery and the thrill of a good deal.

The Conversation

Christopher Lo does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.

– ref. The retail afterlife: How surplus goods find new value at ‘binz’ stores – https://theconversation.com/the-retail-afterlife-how-surplus-goods-find-new-value-at-binz-stores-275057

Tsunami risk in the Mediterranean: why Nice should prepare an evacuation plan

Source: The Conversation – France – By Frédéric Leone, Professeur des Universités, Géographe des risques et des catastrophes "naturelles", Volcanographe, Cartographe, Université Paul Valéry – Montpellier III

According to UNESCO, in 2022, there is a 100% chance of a tsunami of at least one metre high in the Mediterranean Sea in the next 30 years. France’s Côte d’Azur happens to be one of the most seismically active areas in Western Europe. Arno Smit/Unsplash, CC BY

The Mediterranean sea is widely perceived as having a low tsunami risk. History and recent modelling technology have demonstrated that destructive waves have already hit the French coast and could do so again. The results of a project carried out in Nice and along the French Riviera show why anticipation and preventive evacuation measures remain the only truly effective means of saving lives.

Tsunamis, formerly known as tidal waves, raz-de-marée in France or maremoti in Italy, are among the most destructive natural phenomena. Triggered by earthquakes, underwater landslides or volcanic eruptions, they spread rapidly over long distances before releasing their energy near the coast in the form of sudden submersion and extremely powerful currents.

From several centimetres to several metres, this flooding is generally characterised by several waves, and the first waves are not necessarily the largest. The speed of the current is such that the pressure exerted on coastal infrastructure can reach several tons per square metre

Since 1970, tsunamis have claimed more than 250,000 lives worldwide, notably the Boxing day tsunami in 2004 in the Indian ocean and the tsunami on March 11 2011 in Japan, for instance.

A risk that is not so farfetched after all

In the collective imagination, tsunamis have long been associated with the Pacific and the Indian ocean. The risk of an offshore tsunami in the Mediterranean has often been considered marginal, and this in itself could be misleading. In June 2022, UNESCO, which is committed to increasing global tsunami risk awareness among coastal communities, declared:

“Statistics show that there is a 100% chance of a tsunami of at least one metre high in the Mediterranean Sea in the next 30 years.”

After the Pacific, the Mediterranean basin holds the highest number of historical tsunamis recorded, of which several have impacted France’s Côte d’Azur coastline.

According to available data, around twenty incidences were reported in the maritime area along the French Riviera between the 16th century and the early 2000s with waves often exceeding two metres.

Evacuation times that are often very short

The sources of Mediterranean tsunamis can be local or distant. In some scenarios, run-up time for the first waves can be under ten minutes, particularly in the event of an underwater landslide or earthquake close to the coast, such as in the Ligurian sea between Corsica and the Italian coast. Conversely, tsunamis generated further away from France, for example off the northern coast of North Africa, can reach the French Riviera in less than 90 minutes.

The Boumerdès earthquake (Algeria) on May 21, 2003 caused havoc along the entire French Mediterranean coastline. A field enquiry showed that eight marinas on the French Riviera experienced significant sea level drops (from 50 cm to 1.5 m), basin purges, strong eddies and currents, and damaged boats, consistent with harbour resonance phenomena. The effects were observed on the French Riviera coastline an hour and a quarter after the earthquake.

Of more local origin, the tsunami in Nice on October 16 1979, triggered by the underwater collapse of part of the construction site for the new commercial port in Nice (Alpes-Maritimes), adjacent to the airport, caused the deaths of eight people and significant damage in Antibes, Cannes and Nice. The phenomenon was observed in Antibes for around thirty minutes.

Another scenario that could occur closer to the coast is that of the seismic tsunami that struck the Ligurian Sea on February 23, 1887], following an underwater earthquake measuring between 6.5 and 6.8 on the Richter scale. Contemporary accounts describe a sudden retreat of the sea by about one metre in Antibes and Cannes, leaving fishing boats high and dry, before the arrival of a wave reaching nearly two metres, which covered the beaches.

These events are a reminder of how we are completely taken by surprise, and how such short spaces of time show the limits of traditional warning systems. Coastal communities’ ability to evacuate quickly becomes crucial.

2 tsunami scenarios could impact Mediterranean coastline (red: seaquake close to Algeria’s coast, green: submarine landslide in the Ligurian sea)
Two tsunami scenarios could impact Mediterranean coastline (red: seaquake close to Algeria’s coast, green: submarine landslide in the Ligurian sea).
Sahal, Leone & Péroche, 2013, Fourni par l’auteur

An operational warning system for France

France has had a national tsunami alert system that has been part of the Centre d’alerte aux tsunamis (Cenalt) since July 2012, in conjunction with the international system coordinated by UNESCO in the Mediterranean. This system makes it possible to rapidly detect potentially tsunami-generating earthquakes and transmit an alert in less than fifteen minutes to the interdepartmental crisis management operational centre (Cogic) and foreign alert centres.

It is then up to the authorities to disseminate alert messages to the population, in particular via the FR-Alert platform, which allows notifications to be sent to the mobile phones of people located in the danger zone.

However, this global system only covers tsunamis caused by distant earthquakes and is not very effective in the case of local tsunamis or those caused by underwater landslides, where the time it takes for the tsunami to reach the coast may be less than the warning time. This is why it is important to raise awareness among coastal populations about detecting warning signs: felt earthquakes, abnormal sea movements, most often seawater retreats preceding the run-up of the tsunami, but not always.

Nice – Côte d’Azur coastline is highly at risk

Along the entire French Mediterranean coastline, an evacuation zone has been defined by government agencies and the University of Montpellier, based on altitude, distance from the sea and historical data. It corresponds to coastal areas with an altitude of less than 5 metres that are less than 200 metres from the sea. Along river mouths, this distance is extended to 500 metres with respect to the estuary.

Including Corsica, 1,700 km of coastline, 187 towns along the French Mediterranean coast, and at least 164,000 residents would be affected. At the height of the summer, an estimated 835,000 beach users would also need to be taken into consideration in the event of a tsunami.

The Nice – Côte d’Azur metropolitan area is vulnerable for a number of reasons: dense urbanisation, strong tourist appeal, and very busy beaches. Our photo analysis and modelling work have enabled us to estimate that tens of thousands of people are present in the area to be evacuated during periods of high visitor numbers (between 10,000 and 87,000 people on the beaches, depending on the season and time of day).

Evacuating ahead of a tsunami: the plan for Nice and surrounding coastal areas

When faced with a tsunami, evacuation is the only effective means of ensuring civilian safety. International experience shows that rapid and well-prepared evacuation procedures can save the vast majority of exposed populations. Reactive evacuation measures, for example, saved 96% of Japanese inhabitants when the major tsunami struck the Tōhoku coast on March 11 2011.

In Nice – Côte d’Azur, a comprehensive evacuation strategy has been developed and supported by scientific research led by the University of Montpellier’s Laboratory of Geography and Land Planning. It is based on optimised walking routes, taking into account slopes, obstacles, travel speeds and congestion points. Refuge sites located out of “waves’ reach” were identified and validated by local authorities, and evacuation routes were devised using algorithms to find the fastest routes.

In total, nearly a hundred refuge sites have been mapped out and incorporated into operational evacuation plans designed to quickly guide people to safe places.

The first Tsunami risk awareness signposts were installed in Nice on February 27 2026
The first tsunami risk awareness signposts were installed in Nice on February 27 2026.
C. Thomin, MNCA, 2026, Fourni par l’auteur

From science to action: preparing the population

Raising tsunami awareness should go beyond evacuation mapping: safety drills such as evacuation exercises, particularly in schools or gradually introducing public warning signage; contribute to encouraging responsible behaviour. Several initiatives like these have been implemented in Nice via a project with students in Montpellier.

In Nice, a publicly accessible information platform with interactive maps also allows users to find evacuation zones, routes and instructions to follow in the event of an alert. These tools contribute to the development of a genuine tsunami risk culture.

Online map indicating evacuation zones, safe places and routes to get to them in the event of a tsunami in Nice
Online map indicating evacuation zones, safe places and routes to get to them in the event of a tsunami in Nice.
LAGAM/UMPV, 2026, Fourni par l’auteur

Becoming ‘Tsunami Ready’ territory

Beyond France’s Côte d’Azur coastal area, the information portal can be applied to other coastlines elsewhere in France and Europe, both in the Mediterranean and overseas, where tsunami run-up times can be just as short.

The initiatives that are being implemented in Nice are in keeping with UNESCO’s Tsunami Ready international recognition programme (TRRP). This 12-point programme aims to certify territories that are capable of anticipating a tsunami risk, prepare their populations and coordinate an appropriate response.

The first towns to be awarded the label and that have benefited from our team’s scientific and technical support were Deshaies in Guadeloupe and Cannes, with Nice set to join the programme in the near future.

When facing a wave that can arrive in a matter of minutes, being prepared to evacuate undoubtedly makes all the difference.


This article was written with the help of Louis Monnier, Monique Gherardi, Matthieu Péroche and Noé Carles, Université de Montpellier Paul-Valéry.


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Frédéric Leone ne travaille pas, ne conseille pas, ne possède pas de parts, ne reçoit pas de fonds d’une organisation qui pourrait tirer profit de cet article, et n’a déclaré aucune autre affiliation que son organisme de recherche.

– ref. Tsunami risk in the Mediterranean: why Nice should prepare an evacuation plan – https://theconversation.com/tsunami-risk-in-the-mediterranean-why-nice-should-prepare-an-evacuation-plan-277683