The coronavirus lockdown likely has caused the largest single-year drop in carbon emissions ever recorded, but according to a new analysis, it achieved that silver lining at the expense of a lot of gold.
“While lower CO2 emissions are nominally a good thing, the cost of achieving them will be astronomical,” according to the analysis from The Breakthrough Institute.
“We calculate that each ton of carbon reduced in 2020 will come at the cost of $1,750 in reduced economic activity,” writes Zeke Hausfather, BTI’s director of climate and energy—“a cost more than an order of magnitude higher than clean energy technologies available today.”
And while the lockdown has shown that global society can change quickly in response to threat, the change will likely only dent the climate-change juggernaut, Hausfather concludes.
“Because atmospheric CO2 concentrations that drive global warming are a result of cumulative emissions,” he writes, “a 5% reduction in current emissions will have relatively little effect on the climate.”
If 2020 emissions drop by 5 percent—a common estimate—the cumulative CO2 concentration in the atmosphere will decline from an anticipated 414.2 parts per million at year’s end to 414.0. (350 ppm is considered stable.)
“The fact that the biggest global economic contraction since the Great Depression will not make a dent in future warming should be sobering,” he tweeted.
Hausfather derives a lesson from the combination of staggering cost and paltry effect—that there are more economical ways to curb emissions than halting economic activity.
“Technology-driven decarbonizing is the only sustainable pathway to achieve long-term reductions in CO2 emissions,” he says.
Alex Trembath, BTI’s deputy director, plotted Hausfather’s cost estimate against comparative costs for other energy technologies. Onshore wind proved the least expensive way to reduce emissions (on the left side of the chart below), followed by natural gas and solar photovoltaic energy:
Alex Trembath, Breakthrough Institute
BTI modeled scenarios in which the COVID-19 declines quickly or lasts longer.
“Under both the base case and new outbreak scenarios, 2020 emissions are very likely to fall between 2.1% and 7.4%, with a central estimate of 4.8%”
The analysis rests on economic projections from the International Monetary Fund and historical rates of decarbonization, which it modifies because BTI expects the rate of decarbonization in 2020 to decline along with the rest of the economy.
“There is also a real risk that the economic downturn could slow down investments in decarbonization technologies needed to drive meaningful and lasting reductions in emissions, leading to higher emissions in the long-run,” Hausfather writes, “particularly if countries do not prioritize job creation measures with decarbonization co-benefits as part of economic recovery efforts.”
