Pressure for action

The scientists hope to add to pressure on governments to fulfill the 2015 Paris Agreement. Last December, almost 200 nations adopted a rulebook for accomplishing the Paris deal’s goal of preventing average global temperatures from rising more than 2 degrees C. above pre-industrial levels, or 1.5 degrees C. if possible.

Since the world has already warmed by 1 degree C. from pre-industrial levels, the most favorable scenarios under mean deciding between whether to allow warming to continue by a half-degree or 1 degree more. But the IPCC, concluded in a major report in October 2018 that a half-degree less warming would cause fewer deaths and illnesses, 0.1 meters less sea rise, and halve the number of people who lacked fresh water.

Substantially fewer heatwaves and droughts would result, it said, and the world’s coral reefs might survive. Limiting global average temperature rise to 1.5 degrees C. also would avert 150 million premature deaths in the 21st century. The report said the planet is on track to cross the threshold of 1.5 degrees C. above pre-industrial levels by as early as 2030, bringing the risk of catastrophic climate change marked by floods, extreme drought, wildfires and food shortages for hundreds of millions of people.

In their report, the scientists outline six major policy steps to bring about a “carbon-free” economy; drastically better energy efficiency and conservation; boost the consumption of plant-based food; enforce stricter protections and restoration of nature; stabilize world population; and reduce short-lived climate pollutants.

“Mitigating and adapting to climate change while honoring the diversity of humans entails major transformations in the ways our global society functions and interacts with natural ecosystems,” the scientists wrote, adding all is not lost already.

“We are encouraged by a recent surge of concern. Governmental bodies are making climate emergency declarations. Schoolchildren are striking,” they concluded. “Ecocide lawsuits are proceeding in the courts. Grassroots citizen movements are demanding change, and many countries, states and provinces, cities and businesses are responding.”