"The IPCC understates a key risk: that self-reinforcing feedback loops could push the climate system into chaos before we have time to tame our energy system". But current nationally determined pledges to take action to reduce warming, when combined, are emphatically "not on track to limit global warming to 1.5°C above pre-industrial levels".
"Limiting warming to (2.7 degrees) is possible within the laws of chemistry and physics", Jim Skea of Imperial College London, one of the authors of the report, said, "but doing so would require unprecedented changes". And the report says, it would become impossible to produce enough food to feed the world's growing population.
That benchmark is lower than the one set by the global Paris Agreement, which aimed to prevent the planet from warming by 3 degrees Celsius. Limiting global warming to less than 2ºC will hopefully allow ecosystems and animals to adapt to the gradually rising temperatures. Instead, it risks setting up feedbacks that could fall like unsafe dominos, fundamentally destabilizing the planet.
The global scientific authority on climate change, the IPCC, said the planet has 12 years with which to possibly achieve the 1.5-degree target, but it would require "transformational" change across all areas of society. The ice serves as a shield, reflecting heat back into the atmosphere, but is increasingly being melted into water that absorbs heat instead.
Around 6 percent of insects, 8 percent of plants, and 4 percent of vertebrates are projected to be negatively affected by global warming of 1.5°C, namely by shrinking their natural geographic range, compared with 18 percent of insects, 16 percent of plants and 8 percent of vertebrates for global warming of 2°C. This, in turn, would accelerate the collapse of permafrost, releasing its ancient stores of methane, a super climate pollutant 30 times more potent in causing warming than carbon dioxide. To get a sense of how easy that would be, here's the 2017 statistics from IEA's World Energy Outlook as quoted by Bloomberg: coal accounted for 37 percent of global power generation, which made it the largest single source of electricity. But it is change on a scale we have never experienced before: "There is no historical precedent for the scale of the necessary transitions, in particular in a socially and economically sustainable way".
For some, it could be the difference between "life or death", climate scientist Natalie Mahowald, a lead author on the report, told The Associated Press.
"We appreciate the hard work of the scientists and experts, many from the United States, who developed this report under considerable time pressure", an EPA spokesperson said in a statement.
Developing nations and least developed countries have been asking developed nations, particularly the USA, to take historical and moral responsibility for being one of the largest greenhouse gas emitters.
It is critical that world leaders understand the IPCC report and use it as a template for immediate action.
In any non-nightmarish scenario, world leaders would gather together upon receipt of this report, generated by highly respected scientists at the top of their game (the Intergovernmental Panel on Climate Change), and work overtime to solve the global and systemic problems stemming from overuse of dirty energy sources such as coal and the mass production of greenhouse gases, for two. These, after all, are the spaces where climate change has a tendency to disappear once the headlines move on again. It is an issue of fundamental, data-driven science, an issue of human tragedy, and an issue of planetary ecosystems in peril.