The world is barely 10 years old to control climate change, say US scientists

The world is on the verge of failure when it comes to keeping global warming at moderate levels, and countries will need to take "unprecedented" measures to reduce their carbon emissions during the next decade. of the next decade, according to a historical report published by the highest scientific body studying climate change.

While global emissions show little signs of slowing and as the United States, the world's second-largest carbon dioxide emitter, cancels a series of Obama-era climate measures, the chances of achieving the most ambitious goals of the Paris 2015 agreement seem more and more thin. According to the group, to avoid a race above pre-industrial levels exceeding a warming of 1.5 degrees Celsius (2.7 degrees Fahrenheit), it would require a "rapid and profound" transformation of human civilization of a magnitude never reached before.

"There is no documented historical precedent" for radical change in energy, transportation and other systems required to reach 1.5 degrees Celsius, the Intergovernmental Panel on Evolution wrote. Climate Change (IPCC) in a report requested under the 2015 climate agreement in Paris.

At the same time, however, the report is hopefully received in some circles because it claims that 1.5 degrees Celsius is still possible – if emissions are stopped today, for example, the planet will not reach that temperature . It is also likely to galvanize even more climate action by focusing on 1.5 degrees Celsius, rather than 2 degrees, as a target that the world can not afford to miss.

Nevertheless, the transformation described in the document is breathtaking and the speed of the necessary changes raises inevitable questions as to its feasibility.

Most striking is that, according to the document, global annual carbon dioxide emissions, which account for more than 40 billion tonnes per year, are expected to be drastically reduced by 2030 to keep the world fully below 1 billion. , 5 degrees Celsius or allow only a brief "overshoot" of temperature.

Overall emission reductions over the next decade are likely to exceed 1 billion tonnes per year, more than the current emissions of most of the very large emitting countries. By 2050, the report calls for the gradual or near total elimination of coal combustion.

"It's like a deafening hard-hitting smoke alarm that goes off in the kitchen. We need to put out the fire, "said Erik Solheim, executive director of the United States Environmental Program. He added that the need to completely stop emissions by 2050 or find a way to remove as much carbon dioxide from the air that man put there "means that net zero must be the new world mantra".

The radical transformation would also mean that, in a world with more than 2 billion more people by 2050, vast tracts of land currently used to produce food should instead be converted into growing trees that store carbon. and crops for energy use. . The latter would be used as part of a currently non-existent program to obtain energy from trees or plants, and then to bury the resulting carbon dioxide emissions into the soil, which would lead to to a net subtraction of gas from air – bioenergy with carbon capture and storage, or BECCS.

"Such transitions pose serious challenges for the sustainable management of different land demands for human settlements, food, livestock feed, fiber, bioenergy, carbon storage, biodiversity, and others. ecosystem services, "says the report.

The document in question was produced relatively quickly for the careful and deliberate IPCC, representing the work of nearly 100 scientists. It has been the subject of a complex peer review process involving tens of thousands of comments. The latest "summary for policymakers" of 34 pages was approved during a marathon session by scientists and government officials in Incheon, South Korea, last week.

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The report says the world will have to develop large-scale programs of "negative emissions" to eliminate significant volumes of carbon dioxide from the atmosphere. Although basic technologies exist, they have not spread widely, and scientists have questioned the possibility of scaling up such a program in the short time available.

Sunday's report revealed that the world is unfortunately below target.

The IPCC is considered the definitive source of the state of climate science, but it also tends to be conservative in its conclusions. It is because it is based on a consensus-building process and its results are the result not only of science, but also of negotiating with governments for its specific language.

In Sunday's report, the body described in detail the magnitude and unprecedented nature of the changes that would be needed to keep warming at 1.5 degrees Celsius, but it refrained from taking a specific stance on the opportunity to achieve such an ambitious goal. (A draft had mentioned a "very high risk" of warming above 1.5 degrees Celsius, but this language has now disappeared, even though the basic message is still easily inferred.)

"If you expect the IPCC to jump up and wave the red flags, you'll be disappointed," said Phil Duffy, president of the Woods Hole Research Center. "They will do what they always do, namely to publish very cautious reports in an extremely serene language."

Some researchers, including Duffy, are skeptical of IPCC scenarios that keep warming at 1.5 degrees Celsius, including the use of negative-emission technologies to keep the window open.

"Even if it is technically possible, without aligning the technical, political and social aspects of feasibility, it will not happen," added Glen Peters, research director at the Center for International Climate Research in Oslo. "To limit warming below 1.5 ° C, or even 2 ° C, all countries and sectors must act".

Highlighting the difficulty of interpreting what is possible, the IPCC has indicated in the report two separate figures indicating the remaining "carbon footprint" of the Earth or the amount of carbon dioxide that humans can emit while having a reasonable chance of stay below 1.5 degrees Celsius. The result is that humans are allowed either on 10 or 14 years of current emissions, and no more, on a chance equal to or greater than two-thirds to avoid 1.5 degrees Celsius.

The already limited budget would further decrease if other greenhouse gases, such as methane, are not controlled or if and when Arctic permafrost becomes a major source of new emissions.

In any case, researchers have somewhat increased the carbon budget compared to the situation established by the IPCC in 2013, which is a reason for additional hope.

The new approach saves time and "restores the clock from 1.5 degrees Celsius to" five pm to midnight, "said Oliver Geden, head of the research division of the German Business Institute. international security.

At the same time, the report clearly states that a warming of 1.5 degrees Celsius would be very detrimental and that two degrees, considered at the time as a reasonable goal, could become intolerable in some parts of the world.

"1.5 degrees is the new 2 degrees," said Jennifer Morgan, executive director of Greenpeace International, who was in Incheon to finalize the report.

Specifically, the paper finds that instabilities in Antarctica and Greenland, which could trigger a rise in sea level measured in feet rather than inches, "could be triggered between 1.5 and 2 ° C approximately global warming". Tropical coral reefs are at stake as 70 to 90 of them should disappear at 1.5 degrees Celsius, the report says. At 2 degrees, this number reaches more than 99%.

The report found that maintaining warming at 1.5 degrees Celsius could save an area the size of Alaska, the size of Alaska, permafrost thawing, neutralizing a feedback loop that could lead to even more global emissions. The occurrence of completely ice-free summers in the Arctic Ocean increases from one to one hundred per year to one degree per decade, between 1.5 and 2 degrees, revealed one of the many ways in which a half degree has serious consequences in the real world.

The risks of extreme heat and extreme weather events only increase as temperatures rise, which means that their situation would worsen around the world if it gets warmer.

To avoid this, in just over 10 years, the global percentage of electricity from renewable energies such as solar and wind energy should rise from the current 24% to something like 50 or 60%. The remaining coal and gas power plants should be equipped with technologies, collectively known as carbon capture and storage (CCS), that prevent carbon dioxide emissions into the atmosphere and, instead, funnel to bury it. By 2050, most coal-fired power plants would be closed.

Cars and other means of transport should be oriented more and more towards electrification, powered by these same sources of renewable energy. At present, the transportation sector is far behind the electricity sector with respect to low carbon fuel sources. At present, according to the International Energy Agency, only 4% of road transport is powered by renewable fuels, and the agency only expects an increase of 1% from here 2022.

The statements in the report on the need to dump coal have been challenged by the World Coal Association.

"Although we are still reviewing the project, the World Coal Association believes that any credible solution to the 1.5 degree scenario must focus on emissions rather than fuel," said the interim CEO of the group, Katie Warrick, in a statement. "That's why CCS is so vital."

This is a widely adopted approach by the head of the Environmental Protection Agency, who under President Trump has taken many steps to relax the rules for the coal industry.

In an interview with The Post last week, Andrew Wheeler, acting administrator of the EPA, said that the United States "would continue to participate in the UN efforts," despite the fact that Trump has announced its intention to withdraw from the Parisian climate. agreement as soon as possible.

But specifically questioned what it would take to keep the world below a dangerous level of climate change, Wheeler refused to identify a specific level. The agency's regulatory approach is to enable the coal industry to "continue to innovate clean coal technologies, and these technologies will be exported to other countries."

And turning off most coal plants may not be the most radical change required. For example, the document also envisions rapid changes in agriculture, where methane emissions from livestock, rice and other sources are also expected to fall, even though the world will need to feed growing population.

In the meantime, instead of continuing to deforest large areas for livestock and other purposes, humans should engage in a vast program of reforestation, planting or restoring trees over huge areas.

In the end, "one thing is certain," Niklas Hohne, a scientist at the head of the New Climate Institute, said in a statement.

"If we abandon the goal and do not even try, we will certainly miss a long way."

Juliet Eilperin contributed to this report.