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A major concern for the world’s ecosystems is the possibility of collapse, where landscapes and the societies they support change abruptly. Accelerating stress levels, increasing frequencies of extreme events and strengthening intersystem connections suggest that conventional modelling approaches based on incremental changes in a single stress may provide poor estimates of the impact of climate and human activities on ecosystems. We conduct xperiments on four models that simulate abrupt changes in the Chilika lagoon fshery, the Easter Island community, forest dieback and lake water quality—representing ecosystems with a range of anthropogenic interactions. Collapses occur sooner under increasing levels of primary stress but additional stresses and/or the inclusion of noise in all four models bring the collapses substantially closer to today by ~38–81%. We discuss the implications for further research and the need for humanity to be vigilant for signs that ecosystems are degrading even more rapidly than previo
The accelerating thaw of Antarctica might drive sea levels up by more than five metres by 2300 unless governments act quickly to cut greenhouse gas emissions, a UN report said on Wednesday.
Scientists are getting a better handle on how fast Greenland's ice is flowing out to sea. Old models that used Antarctica as a baseline were way off the mark.
An international team of researchers have sounded new alarm bells about the changing chemistry of the western region of the Arctic Ocean after discovering acidity levels increasing three to four times faster than ocean waters elsewhere. The team, which includes University of Delaware marine chemistry expert Wei-Jun Cai, also identified a strong correlation between the accelerated rate of melting ice in the region and the rate of ocean acidification, a perilous combination that threatens the survival of plants, shellfish, coral reefs and other marine life and biological processes throughout the planet's ecosystem.
On estime qu'entre 100 millions et un milliard d'oiseaux meurent chaque année en heurtant des bâtiments aux États-Unis, les lumières artificielles jouant un rôle majeur dans ce bilan. Mais les effets de la pollution lumineuse sur le monde naturel seraient encore bien plus importants.
Climate scientists are clear that it’s already too late to go back to the kind of weather we used to have, but can we stop things from getting a whole lot worse? Professor Michael E Mann – from Penn State university in the United States – and author of ‘The New Climate War’ explains the radical change needed to avert catastrophic temperature rises.
A new analysis of flash droughts finds that droughts coming on suddenly seem to be striking faster in the last two decades, with approximately 33–46 percent of flash droughts now emerging within just five days.
Fresh water cycles from ocean to air to clouds to rivers and back to the oceans. This constant shuttling can give us the illusion of certainty. Fresh water will always come from the tap. Won’t it? Unfortunately, that’s not guaranteed. Climate change is shifting where the water cycle deposits water on land, with drier areas becoming drier still, and wet areas becoming even wetter.
How close is nuclear fusion to break-even? If you trust the headlines we're getting close and the international project ITER is going to be the first to produce energy from fusion power. But not so fast. Scientists have, accidentally or deliberately, come to use a very misleading quantity to measure their progress. Unfortunately we're much farther away from generating fusion power than the headlines suggest. "Donc, si tout va bien, l'EROEI d'ITER sera de 0,4 ou 0,5 pour 1 - encore plus minable qu'un biocarburant basé sur les algues. " - Philippe Gauthier
Don't you stumble, sometimes, into something that seems to make a lot of sense, but you can't say exactly why? For a long time, I had in mind the idea that when things start going bad, they tend to go bad fast. We might call this tendency the "Seneca effect" or the "Seneca cliff," from Lucius Annaeus Seneca who wrote that "increases are of sluggish growth, but the way to ruin is rapid."
The huge amount of money poured into the recovery from the pandemic—around $16 trillion, by the latest count—could have helped launch the world on a path to cut emissions quickly enough to meet the goals of the Paris climate agreement. But only around 2% of the spending is going to clean energy so far,
Scientists just completed one of the most comprehensive investigations of Earth’s climate history—and the findings aren’t favorable. They found that the planet could eventually warm to levels it hasn’t reached in at least 34 million years.
What could bring down the industrial civilization? Would it be global warming (fire) or resource depletion (ice)? At present, it may well be that depletion is hitting us faster. But, in the long run, global warming may hit us much harder. Maybe the fall of our civilization will be Fire AND ice.
