Just two years ago, amid global fanfare, the Paris climate accords were signed — initiating what seemed, for a brief moment, like the beginning of a planet-saving movement. But almost immediately, the international goal it established of limiting global warming to two degrees Celsius began to seem, to many of the world’s most vulnerable, dramatically
As part of the Paris agreement, the International Panel on Climate Change (IPCC) was asked “to provide a special report in 2018 on the impacts of global warming of 1.5 [degrees Celsius] above pre-industrial levels and related global greenhouse gas emission pathways.” That report was released on October 8.
AROUND THE MIDDLE of the last century, the chemical DDT was found to pose a risk to human and animal health. The ultimate response — after a prolonged fight between environmentalists and the chemical industry — was a federal ban on all uses of the substance found to be unsafe.
In July of this year, during record-smashing heat waves and forest fires, a group of scientists published “Trajectories of the Earth System in the Anthropocene,” exploring the risk that climate feedbacks could lead to runaway heating and a “Hothouse Earth.” Will Steffen, Johan Rockström, and Katherine Richardson — from the Universities of Stockholm, Australia, and Copenhagen, with colleagues from Stanford, Cambridge, Potsdam, The Netherlands, and elsewhere — published the paper in the US
If your colleague or child does well and you give her or him positive feedback, that’s good.
If climate change causes a cascade of impacts that result in additional climate change — which scientists call "positive feedback" — that’s bad, and maybe catastrophic.
