The United Nations says that the world has failed in the goal set out in the Paris Climate Agreement to limit global warming to 1.5 degrees Celsius above pre-industrial levels.
According to a report from the UN Environment Programme (UNEP) released on September 2, global warming is set to cross the 1.5 degree threshold by the end of the decade. The UN also warned that every fraction of a degree of overshoot above that threshold will dramatically accelerate glacial melt, ecosystem losses and economic impacts.
"There are no good outcomes above 1.5 degrees," the report reads. "Human health, food and water security, cities and infrastructure will come under increasing strain. These impacts will not be distributed equally, and some losses will be irreversible even if global temperatures eventually decline."
The report calls for an “overshoot, peak and decline” strategy to limit the damage, pairing aggressive and immediate cuts to emissions with measures to remove carbon dioxide from the atmosphere by blanketing large sections of the world with new forests. However, it could still take decades — or even centuries — for such a plan to fully be realized, and in the meantime, weather-related disasters continue to ramp up in intensity and frequency.
The world's supply chains have also already started to feel the impacts of climate change in recent years. In Europe, historic drought conditions have pushed river levels to record lows, while failed harvests have threatened global food supplies, and floods have repeatedly shut down factories and critical transportation routes.
At the current pace of global warming, the planet is expected to warm by 2.6 degrees Celsius above pre-industrial times by the end of the century. For a frame of reference, the UNEP estimates that exposure to overlapping climate risks would double between 1.5 and 2 degrees, and then double again between 2 and 3 degrees. Once warming approaches 3 degrees, the Arctic could be fully ice-free for several months each year, locking in multiple meters of sea level rise, and substantially increasing the risk of widespread ecosystem collapse across the globe.
