(CN) – It’s not exactly the day after tomorrow, but a landmark report Monday from the United Nations puts a tighter-than-expected deadline for countries to meet the goals of the Paris climate agreement.
“If the current warming rate continues, the world would reach human-induced global warming of 1.5 degrees Celsius around 2040,” says the report from the U.N. Intergovernmental Panel on Climate Change.
At 728 pages – with more than 6,000 scientific citations – the sobering report from the Nobel Prize-winning international agency offers a grim forecast of what will satisfy the Paris agreement goal of keeping global temperatures well below 2 degrees higher than preindustrial levels.
“Many regions of the world have already experienced greater regional-scale warming, with 20 to 40 percent of the global population (depending on the temperature dataset used) having experienced over 1.5 degrees Celsius of warming in at least one season temperature rise to date has already resulted in profound alterations to human and natural systems, bringing increases in some types of extreme weather, droughts, floods, sea level rise and biodiversity loss, and causing unprecedented risks to vulnerable persons and populations,” the report notes in Chapter 1.
Panmao Zhai, who co-chairs the agency’s Working Group I, noted that this report underscores the toll of climate change already underway.
"One of the key messages that comes out very strongly from this report is that we are already seeing the consequences of 1 degree Celsius of global warming through more extreme weather, rising sea levels and diminishing Arctic sea ice, among other changes,” Zhai said in a statement.
Limiting warming to 1.5 degrees Celsius – instead of the half-degree higher that the Paris accord allows – could be a matter of life and death for millions, particularly in coastal regions, island nations and underdeveloped nations.
As summarized by the Associated Press, it would mean that half would suffer from lack of water; fewer would die from heat- and smog-related illnesses, and sea levels would rise 4 inches less.
The new goal could also save the West Antarctic ice sheet from irreversible melting and save most of the world’s coral reefs from dying.
“Limiting warming to 1.5 degrees Celsius can be achieved synergistically with poverty alleviation and improved energy security and can provide large public health benefits through improved air quality, preventing millions of premature deaths,” the report states.
Reaching this goal will be difficult with two of the world’s biggest polluters in the thrall of right-wing leaders antagonistic to the more modest goals of the Paris agreement: President Donald Trump announced his intention to withdraw the United States from the agreement as soon as the treaty allows it, and Brazil appears ready to elect Jair Bolsonaro, another foe of the accord who has expressed sympathy for the military dictatorship that ruled there between 1964 and 1985.
The United States ranks second among greenhouse gas-emitting nations, spewing 5,414 metric tons of carbon dioxide a year as of 2017. The New York Times noted that Brazil ranks seventh.
Amid the gloomy news, U.N. Secretary General Antonio Guterres expressed optimism.
“It is not impossible to limit global warming to 1.5ºC, according to the new @IPCC_ch report,” Guterres tweeted. “But it will require urgent, unprecedented & collective #ClimateAction in all areas. There is no time to waste.”
The secretary-general’s words echo those of the report, which urges immediate action.
“All pathways begin now and involve rapid and unprecedented societal transformation,” it states. ”An important framing device for this report is the recognition that choices that determine emissions pathways, whether ambitious mitigation or ‘no policy’ scenarios, do not occur independently of these other changes and are, in fact, highly interdependent. “
The report notes that poorer nations will bear the brunt of climate inaction.
“The most affected people live in low and middle income countries, some of which have already experienced a decline in food security, linked in turn to rising migration and poverty,” the report notes. “Small islands, megacities, coastal regions and high mountain ranges are likewise among the most affected.”