12 years to limit catastrophe
There are only a dozen years for global warming to be kept to a maximum of 1.5 C, beyond which even half a degree will significantly worsen the risks of drought, floods, extreme heat and poverty for millions of people. Maps below show different worlds: 1.5 vs 2 C
Avoiding global climate chaos will require a major transformation of society and the world economy that is “unprecedented in scale,” the UN said yesterday in a landmark report that warns time is running out to avert disaster.
Earth’s surface has warmed one degree Celsius (33.8 degrees Fahrenheit) — enough to lift oceans and unleash a crescendo of deadly storms, floods and droughts — and is on track towards an unliveable 3C or 4C rise. At current levels of greenhouse gas emissions, we could pass the 1.5C marker as early as 2030, and no later than mid-century, the Intergovernmental Panel for Climate Change (IPCC) reported with “high confidence”.
“The next few years are probably the most important in human history,” Debra Roberts, head of the Environmental Planning and Climate Protection Department in Durban, South Africa, and an IPCC co-chair, said. A Summary for Policymakers of the 400-page tome underscores how quickly global warming has outstripped humanity’s attempt to tame it, and outlines options for avoiding the worst ravages of a climateaddled future. “We have done our job, we have now passed on the message,” Jim Skea, a professor at Imperial College London’s Centre for Environmental Policy and an IPCC co-chair, said. “Now it is over to governments — it’s their responsibility to act on it.”
The IPCC report, however, shows that global warming impacts have come sooner and hit harder than predicted.
“Things that scientists have been saying would happen further in the future are happening now,” Jennifer Morgan, Executive Director of Greenpeace International, said. To have at least a 50/50 chance of staying under the 1.5C cap without overshooting the mark, the world must, by 2050, become “carbon neutral”, according to the report. “That means every tonne of CO2 we put into the atmosphere will have to be balanced by a tonne of CO2 taken out,” said lead coordinating author Myles Allen, head of the University of Oxford’s Climate Research Programme.
Alandmark 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 yesterday by the Intergovernmental Panel on Climate Change (IPCC), a group of scientists convened by the United Nations to guide world leaders, warned that to prevent 1.5 degrees Celsius of global warming, greenhouse pollution must be reduced by 45 per cent from 2010 levels by 2030, and 100 per cent by 2050.
If no action is taken immediately to reduce greenhouse emissions by 2030, it will lead to 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. “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.
What is the one big takeaway?
The authors found if greenhouse gas emissions continue at the current rate, the atmosphere will warm up by as much 1.5 degrees Celsius above preindustrial 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, 2 degree Celsius, 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 1.5 Celsius mark.
What does the world need to do?
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 $54 trillion. But while they conclude that it is technically possible to achieve the rapid changes required to avoid 1.5C of warming, they concede that it may be politically unlikely. For instance, the report says that heavy taxes on carbon dioxide emissions - perhaps as high as $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.
How much will tackling climate change cost?
It won’t come cheap. The report says that to limit warming to 1.5C, it will involve “annual average investment needs in the energy system of around $2.4 trillion” between 2016 and 2035. But experts believe that this number defintely needs to be put in context. “There are costs and benefits you have to weigh up,” Dr Stephen Cornelius, a former UK IPCC negotiator now with WWF, told the BBC. He said that cutting emissions hard in the short term will cost money, but is cheaper than paying for carbon dioxide removal later this century.
Who all compiled the report?
The report was written and edited by 91 scientists from 40 countries who analyzed more than 6,000 scientific studies. The Paris agreement set out to prevent warming of more than 2 degree Celsius above preindustrial 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 1.5 degree Celsius of warming.
Are all world leaders on the same page?
Not really. US President Donald Trump, who has mocked the science of climate change, has vowed to increase the burning of coal and said he intends to withdraw from the Paris agreement. And 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 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.”
What happens if no one takes action?
Absent aggressive action, many effects once expected only several decades in the future will arrive by 2040, and at the lower temperature. “It’s telling us we need to reverse emissions trends and turn the world economy on a dime,” said Myles Allen, an Oxford University scientist and an author of the report. Global sealevel will rise around 10cm more if we let warming go to 2C. Keeping to 1.5C means that 10 million fewer people would be exposed to the risks of flooding.
So what needs to be done now by the world?
To prevent 1.5C of warming, the report said, by 2050 use of coal as an electricity source would have to drop from nearly 40 per cent today to up to 7 per cent. Renewables such as wind and solar, which make up about 20 per cent of the energy mix today, would have to increase to as much as 67 per cent. “There is no way to mitigate climate change without getting rid of coal,” said Drew Shindell, a climate scientist at Duke University and an author of the report.