A LANDMARK report from the United Nations’ scientific panel on climate change paints a far more dire picture of the immediate consequences of climate change than previously thought, and says that avoiding the damage requires transforming the world economy at a speed and scale that has “no documented historic precedent”.
The report, issued last Monday by the Intergovernmental Panel on Climate Change (IPCC), describes a world of worsening food shortages and wildfires, and a mass die-off of coral reefs as soon as 2040 — a period well within the lifetime of much of the global population.
The report “is quite a shock, and quite concerning”, said Bill Hare, an author of previous IPCC reports and a physicist with Climate Analytics, a nonprofit organisation.
“We were not aware of this just a few years ago.” The report was the first to be commissioned by world leaders under the Paris agreement, the 2015 pact by nations to fight global warming.
The authors found that if greenhouse gas emissions continue at the current rate, the atmosphere will warm up by as much as 2.7°F (1.5°C) above pre-industrial levels by 2040, inundating coastlines and intensifying droughts and poverty. Previous work had focused on estimating the damage if average temperatures were to rise by a larger number, 3.6°F (2°C), because that was the threshold scientists previously considered for the most severe effects of climate change.
The new report, however, shows that many of those effects will come much sooner, at the 2.7-degree mark.
Avoiding the most serious damage requires transforming the world economy within just a few years, said the authors, who estimate that the damage would come at a cost of US$54 trillion (RM224.6 trillion). But while they conclude that it is technically possible to achieve the rapid changes required to avoid 2.7 degrees of warming, they concede that it may be politically unlikely.
For instance, the report says that heavy taxes or prices on carbon dioxide emissions — perhaps as high as US$27,000 per ton by 2100 — would be required. But such a move would be almost politically impossible in the United States, the world’s largest economy and second-largest greenhouse gas emitter behind China. Lawmakers around the world, including in China, the European Union and California, have enacted carbon pricing programmes.
President Donald Trump, who has mocked the science of human-caused climate change, has vowed to increase the burning of coal and said he intends to withdraw from the Paris agreement. And on Sunday in Brazil, the world’s seventh-largest emitter of greenhouse gas, voters appeared on track to elect a new president, Jair Bolsonaro, who has said he also plans to withdraw from the accord.
The report was written and edited by 91 scientists from 40 countries who analysed more than 6,000 scientific studies. The Paris agreement set out to prevent warming of more than 3.6 degrees above pre-industrial levels — long considered a threshold for the most severe social and economic damage from climate change. But the heads of small island nations, fearful of rising sea levels, had also asked scientists to examine the effects of 2.7 degrees of warming.
Absent aggressive action, many effects once expected only several decades in the future will arrive by 2040, and at the lower temperature, the report shows.
To prevent 2.7 degrees of warming, the report said, greenhouse pollution must be reduced by 45 per cent from 2010 levels by 2030, and 100 per cent by 2050. It also found that, by 2050, use of coal as an electricity source would have to drop from nearly 40 per cent today to between one and seven per cent. Renewable energy such as wind and solar, which make up about 20 per cent of the electricity mix today, would have to increase to as much as 67 per cent.
The World Coal Association disputed the conclusion that stopping global warming calls for an end of coal use. In a statement, Katie Warrick, its interim chief executive, noted that forecasts from the International Energy Agency, a global analysis organisation, “continue to see a role for coal for the foreseeable future”.
Despite the controversial policy implications, the US delegation joined more than 180 countries last Saturday in accepting the report’s summary for policymakers, while walking a delicate diplomatic line. A US State Department statement said that “acceptance of this report by the panel does not imply endorsement by the United States of the specific findings or underlying contents of the report”.
The state department delegation faced a conundrum. Refusing to approve the document would place the US at odds with many nations and show it rejecting established academic science on the world stage. However, the delegation also represents a president who has rejected climate science and climate policy.
The report attempts to put a price tag on the effects of climate change. The estimated US$54 trillion in damage from 2.7 degrees of warming would grow to US$69 trillion if the world continues to warm by 3.6 degrees and beyond, the report found, although it does not specify the length of time represented by those costs.
In addition, it said, the United States along with Bangladesh, China, Egypt, India, Indonesia, Japan, the Philippines and Vietnam are home to 50 million people who will be exposed to the effects of increased coastal flooding by 2040, if 2.7 degrees of warming occur.
At 3.6 degrees of warming, the report predicts a “disproportionately rapid evacuation” of people from the tropics. “In some parts of the world, national borders will become irrelevant,” said Aromar Revi, director of the Indian Institute for Human Settlements and an author of the report. “You can set up a wall to try to contain 10,000 and 20,000 and one million people, but not 10 million.”
The report concludes that the world is already more than halfway to the 2.7-degree mark — human activities have caused warming of about 1.8 degrees since the 1850s, the beginning of large-scale industrial coal burning. NYT