The gap is widening between the goal of limiting global warming to no more than 2° Celsius this century and what is realistically achievable, U.N. Environment warned.
Almost 200 nations signed onto the landmark 2015 Paris Agreement on climate change that committed the world to “holding the increase in the global average temperature to well below 2° above pre-industrial levels and pursuing efforts to limit the temperature increase to 1.5° above pre-industrial levels.”
But the world's average temperatures have already increased 1° since pre-industrial levels, so the real choice is whether to allow it to heat up by a half-degree or 1° more.
And the world's greenhouse gas emissions, instead of decreasing, rose in 2017 by 0.7 gigatons to 53.5 gigatons, after three years of decreases.
To limit global warming to 1.5°, global greenhouse gas emissions must be reduced 55% by 2030, the U.N. environmental agency, known as UNEP, said. To limit global warming to 2°, they must be reduced 25%.
That means nations' goals and what they are doing to address the problem is wider than ever, UNEP concluded in its ninth annual assessment of nations' targets and policies for cutting industrial carbon dioxide emissions.
Nations will now have to triple their efforts to succeed in limiting warming to no more than a half-degree more and it will take a fivefold effort to limit it to 1° more, the U.N. agency said. Global emissions would need to peak by 2020, then start quickly subsiding.
CO2 emissions rise for first time in four years
The assessment comes on the eve of a major U.N. climate conference in Katowice, Poland scheduled to be held from December 2nd to 14th. The goal of the talks is to produce a “rule book” on how to implement the 2015 Paris Agreement.
The stakes could not be higher. The U.N.'s Nobel Prize-winning panel on climate change reported last month no hope remains for holding off all of the most dangerous projections.
The Intergovernmental Panel on Climate Change, or IPCC, said even the most optimistic scenarios for halting the rise in average global temperatures will mean serious repercussions for the planet and future generations.
UNEP found, however, that the United States and six other major countries are lagging far behind on the pledges they made in Paris.
“If the IPCC report represented a global fire alarm, this report is the arson investigation,” UNEP's Deputy Executive Director Joyce Msuya said of her agency's latest findings.
“The science is clear," she said. "For all the ambitious climate action we’ve seen, governments need to move faster and with greater urgency. We’re feeding this fire, while the means to extinguish it are within reach.”
But if nothing changes in how the world confronts climate change, current policies will produce a temperature rise of 3.2° by the end of this century, UNEP concluded.
"We must think of generations to come. At the moment we are headed for a world of cataclysm and uncertainty due to climate disruption," U.N. Secretary-General António Guterres said. "The world's top scientists have warned that we have little time left to limit temperature rise to 1.5° until the end of the century.
