« Dans la quête aux réductions d’émissions de CO2, on parle régulièrement de différents leviers : démographie, décroissance, sobriété, efficacité énergétique ou encore mix énergétique. Pour comprendre l’impact de chacun de ces termes, il est commode de se servir de l’équation de Kaya. Cette équation, que l’on doit à l’économiste japonais Yoichi Kaya, décompose les émissions de CO2 énergétiques (donc qui proviennent de la consommation d’énergie) selon une formule mathématique qui n’est qu’une tautologie, mais qui donne un axe de lecture intéressant. Dans « Environment, Energy, and Economy : strategies for sustainability« , il écrit en 1997 que la quantité de CO2 énergétique émise dans l’atmosphère est égale à l’intensité carbone de l’énergie, multipliée par l’intensité énergétique du PIB, multipliée par le PIB par habitant, multiplié par la population. » … Simon Yaspo.
More than 40% of land vertebrates will be threatened by extreme heat by the end of the century under a high emissions scenario, with freak temperatures once regarded as rare likely to become the norm, new research warns. Reptiles, birds, amphibians and mammals are being exposed to extreme heat events of increasing frequency, duration and intensity, as a result of human-driven global heating. This poses a substantial threat to the planet’s biodiversity, a new study warns. Under a high emissions scenario of 4.4C warming, 41% of land vertebrates will experience extreme thermal events by 2099, according to the paper, published in Nature.
Materials put into domestic compost are failing to disintegrate after six months – the only solution is to use less. Most plastics marketed as “home compostable” don’t actually work, with as much as 60% failing to disintegrate after six months, according to research.
Industry groups representing some of the world’s largest companies are “opposed to almost all major biodiversity-relevant policies” and are lobbying to block them, according to a new report. Researchers found that 89% of engagement by leading industry associations in Europe and the US is designed to delay, dilute and block progress on tackling the biodiversity crisis, which scientists say is as serious as the climate emergency.
Sustainable food systems are a cornerstone to cutting emissions but have been largely absent from the agenda in Glasgow. Farming is a complex issue on the journey to net zero, as it is both a source and sink for emissions. About 20% of global emissions come from agriculture and land use, and this rises to more than 25% for the food system as a whole, which includes processing, packaging and transport.
