« 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.
Humanity is not on track to avoid the deadliest effects of climate change, according to University at Buffalo researcher Holly Jean Buck. "Our plans are not adequate to meet the goal of limiting the Earth's temperature increase to no more than 1.5℃ by 2050," said Buck, Ph.D., assistant professor of environment and sustainability....
Net-zero targets imply that continuing residual emissions will be balanced by carbon dioxide removal. However, residual emissions are typically not well defined, conceptually or quantitatively. We analysed governments’ long-term strategies submitted to the UNFCCC to explore projections of residual emissions, including amounts and sectors. We found substantial levels of residual emissions at net-zero greenhouse gas emissions, on average 18% of current emissions for Annex I countries. The majority of strategies were imprecise about which sectors residual emissions would originate from, and few offered specific projections of how residual emissions could be balanced by carbon removal. Our findings indicate the need for a consistent definition of residual emissions, as well as processes that standardize and compare expectations about residual emissions across countries. This is necessary for two reasons: to avoid projections of excessive residuals and correspondent unsustainable or unfeasible carbon-removal level
