Climate pollution equal to about 27 times humans’ 2015 carbon dioxide emissions may have to be removed from the atmosphere and locked underground forever in order to keep the globe from warming beyond 1.5°C (2.7°F) above preindustrial levels, according to a new study.
The research, led by scientists at the International Institute for Applied Systems Analysis, or IIASA, in Austria, adds to the mounting evidence that countries will have to physically remove carbon dioxide from the atmosphere to prevent global warming from exceeding dangerous levels.
Removing carbon dioxide from the atmosphere is called “negative emissions,” and it’s central to the Paris climate agreement, which aims to prevent the globe from heating beyond 2°C (3.6°F). One of the main goals of the agreement is to keep warming to 1.5°C, a goal growing more difficult as the U.S. and other countries waver on their commitments to cut emissions.
Human greenhouse gas emissions will have to peak globally within 10 years for the 1.5°C target to be met, according to the study.
“Emissions need to peak very soon because the CO2 emitted now doesn't disappear, or stop trapping heat, even if we were to reach full decarbonization,” said the study’s lead author Brian Walsh, a former IIASA researcher now consulting for the World Bank. “Emissions need to not only peak but begin a rapid decrease soon in order to have a plausible shot at meeting the 1.5°C target.”
Turning emissions around so quickly will involve humans completely weaning themselves from fossil fuels use by around 2050 and widely implementing negative emissions techniques, Walsh said.
Glen Peters, a global carbon cycle researcher at the Center for International Climate Research in Norway, who is unaffiliated with the study, said emissions need to fall as fast as they have increased in recent years, something that will take ever-more heroic efforts if climate pollution is to peak within a decade.
“It’s hard to see 2°C without some sort of negative emissions,” he said.
Read more at A Cooler Future May Hinge on Removing CO2 from the Air