Flux continu

The ecological concept of human carrying capacity is necessarily complicated because human beings are the ‘ultimate ecosystem engineers’ who moderate the environment for their benefit. For at least the last few hundred years, human ingenuity, access to massive stocks of fossil fuels, and technological development have driven facilitation whereby increasing human abundance has promoted higher population growth rates. However, this positive relationship broke down during the 1950s, and by 1962, the global human population entered a phase where the growth rate consistently declined as population increased. The onset of this negative phase occurred 8 years before a global biocapacity deficit began in 1970. The onset of the negative phase also varies regionally, with the lowest-income and highest fertility regions entering this phase later than higher-income regions. A Ricker logistic model fitted to the negative phase predicts that the global population could reach 11.7–12.4 billion people between 2067 and 2076.

Climate models simulate a wide range of 21st century warming for a given forcing scenario. Constraining this uncertainty is a central challenge in climate science because of its implications for climate policy and adaptation. The Transient Climate Response (TCR) is a key idealized metric used to quantify future warming in response to an exponentially increasing CO2 concentration. Climate models span a range of 1.3–3 K for TCR. In attempts to constrain this range, emergent constraints on TCR based on historical temperature trends consistently pointed towards TCR values at the lower end of the range of models. However, recent evidence from trends in the short-wave and long-wave components of Earth's energy imbalance (EEI) at the top-of-atmosphere suggests that models with higher TCR lie closer to the observed EEI trends. Here, we reconcile this discrepancy and provide a revised range for TCR of 1.9–2.6 K. Using a statistical variability-filtering approach, we show that previous temperature-based constraints we

Modeling the energy limits to business-as-usual scenarios : confronting peak oil to the energy transition

Climate models simulate a wide range of 21st century warming for a given forcing scenario. Constraining this uncertainty is a central challenge in climate science because of its implications for climate policy and adaptation. The transient climate response (TCR) is a key idealized metric used to quantify future warming in response to an exponentially increasing CO2 concentration. Climate models span a range of 1.3–3 K for TCR. In attempts to constrain this range, emergent constraints on TCR based on historical temperature trends consistently pointed toward TCR values at the lower end of the range of models. However, recent evidence from trends in the short-wave and long-wave components of Earth's energy imbalance (EEI) at the top-of-atmosphere suggests that models with higher TCR lie closer to the observed EEI trends. Here, we reconcile this discrepancy and provide a revised range for TCR of 1.9–2.6 K. Using a statistical variability-filtering approach, we show that previous temperature-based constraints wer

Global energy and materials are essential to the functioning of the economy and have significant implications for macroeconomics and the environment. At the same time, the world is not on track to meet Paris Agreement goals. This paper documents two stylized facts that connect these observations. First, the world economy is characterized by large embedded emissions and materials: different energies and materials are deeply entwined and interdependent. This has historically led to additive – rather than substitution – dynamics in energy and materials on a global scale. Second, historically there has been a strong positive correlation between efficiency in resource use and total resource use at a global scale. We synthesize these observations by introducing the Generalized Jevons Paradox (GJP). We argue that the GJP reflects the direct and indirect energy/material demand effects of long-term energy and material interdependencies, themselves shaped by market and geoeconomic power, trade arrangements, and financi

For most of the modern era, capitalism justified itself through growth. Industrial societies converted vast amounts of fossil energy into production, wealth, and rising living standards. Roads, bridges, power grids, schools, and public institutions expanded alongside the economy. Inequality and exploitation remained deeply embedded in the system, but they were partly obscured by a broader story of material progress.

Cet article rapporte la difficulté du secteur manufacturier en Grande Bretagne à faire face à l’augmentation du cout de l'énergie. Dans l'ombre de cet article apparait ce qui sera la réalité à un moment donné, sans pétrole bon marché, l'industrie manufacturière ne peut pas fonctionner dans les conditions actuelles. Le contrat social sera rompu et il faudra réinventer une manière de vivre ensemble. La situation en Grande Bretagne est peut-être exacerbée par le Brexit et la situation insulaire mais elle est l'avant-poste de ce qui attend une bonne part du monde industrialisé, à moins de relancer le charbon avec toutes les conséquences sur le dérèglement climatique et la santé des personnes que nous connaissons.

C’est un indicateur climatique peu connu, et il part en vrille. Son nom : le déséquilibre énergétique de la Terre. Sa conséquence : il pourrait accélérer le réchauffement climatique bien au-delà de nos prévisions.

Current energy projections often envision an expansion of nuclear capacities to decarbonize future energy systems. However, this contrasts with the historic and current status of the nuclear industry, marked by techno-economic challenges for both light-water and non-light-water reactor technologies. Regardless, projections of strong nuclear growth have persisted since the 1970s. This paper investigates the “nuclear energy paradox” which shows the recurring divergence between historical projections and actual developments. A data compilation of long-term energy projections from international organizations such as the IAEA and the IEA as well as energy system models like GCAM and MESSAGE, as used in the IPCC, reveal a recurring pattern of high-growth projections for nuclear power. Such projections often rest on techno-economic assumptions such as substantial cost reductions. We propose the concept of nuclear imaginaries to show that these assumptions are embedded into techno-economic visions of nuclear power de

La production d'acier mondiale, responsable de 11% des émissions de gaz à effet de serre d'origine humaine, reste largement dépendante du charbon et les capacités de production d'acier "vert" n'ont que "très légèrement" augmenté en 2025, déplore l'ONG américaine Global Energy Monitor lundi. Pour transformer le minerai de fer en acier, les hauts fourneaux traditionnels consomment du charbon d'origine fossile, très polluant. Ils contribuent ainsi significativement au réchauffement de l'atmosphère.