Rapid greenhouse-gas emissions reductions are needed if governments want to keep in check both the costs of the transition towards climate stabilization and the amount of removing already emitted CO2 from the atmosphere. To this end, emissions in 2030 would need to be at least 20 percent below what countries have pledged under the Paris climate agreement, a new study finds – an insight that is directly relevant for the global stock-take scheduled for the UN climate summit in Poland later this year. Removing CO2 from the atmosphere through technical methods including carbon capture and underground storage (CCS) or increased use of plants to suck up CO2 comes with a number of risks and uncertainties, and hence the interest of limiting them.
Rapid greenhouse-gas emissions reductions are needed if governments want to keep in check both the costs of the transition towards climate stabilization and the amount of removing already emitted CO2 from the atmosphere. To this end, emissions in 2030 would need to be at least 20 percent below what countries have pledged under the Paris climate agreement, a new study finds – an insight that is directly relevant for the global stock-take scheduled for the UN climate summit in Poland later this year. Removing CO2 from the atmosphere through technical methods including carbon capture and underground storage (CCS) or increased use of plants to suck up CO2 comes with a number of risks and uncertainties, and hence the interest of limiting them.
“Emissions reduction efforts in the next decade pledged by governments under the Paris climate agreement are by far not sufficient to attain the explicit aim of the agreement – they will not keep warming below the 2-degrees-limit,” says Jessica Strefler from the Potsdam Institute for Climate Impact Research (PIK), lead-author of the analysis published in Environmental Research Letters. “To stabilize the climate before warming crosses the Paris threshold, we either have to undertake the huge effort of halving emissions until 2030 and achieving emission neutrality by 2050 – or the emissions reductions would have to be complemented by CO2 removal technologies. In our study, we for the first time try to identify the minimum CO2 removal requirements – and how these requirements can be reduced with increased short-term climate action.”
At least 5 billion tons of CO2 removal per year throughout the second half of the century
It turns out that, according to the computer simulations done by the scientists, challenges for likely keeping warming below the threshold agreed in Paris would increase sharply if CO2 removal from the atmosphere is restricted to less than 5 billion tons of CO2 per year throughout the second half of the century. This is substantial. It would mean for instance building up an industry for carbon capture and storage that moves masses comparable to today’s global petroleum industry. Still, 5 billion tons of CO2 removal is modest compared to the tens of billion tons that some scenarios used in climate policy debates assume. Current CO2 emissions worldwide are more than 35 billion tons per year.
Read more at Potsdam Institute for Climate Impact Research (PIK)
Photo credit: StockSnap via Pixabay
