By Kenneth Richard on 14. December 2023
The benefits of not meeting Paris Accord emissions-reduction targets outweigh the costs associated even with worst-case-scenario global warming throughout the 21st century.
A new comprehensive analysis (Tol, 2023) weighs the cost-benefit of meeting Paris Accord emission policy targets to keep global warming in check, or under 2°C.
The analysis reveals that even in the best case scenarios (that assume emission reduction policies fully meet their avoided-warming targets), as well as in the worst case scenarios (that assume “constant vulnerability” to global-warming-induced climate disasters and widespread economic austerity), the tens of trillions of USD costs associated with moving away from fossil fuel consumption to reach net-zero emissions by 2050 (4.8% of GDP) still outweigh the net benefit losses (3.0% of GDP) in 2100.
“The central estimate of the costs of climate policy, unrealistically assuming least-cost implementation, is 3.8–5.6% of GDP in 2100. The central estimate of the benefits of climate policy, unrealistically assuming high no-policy emissions and constant vulnerability, is 2.8–3.2% of GDP.”
There is a nearly 10 times worse cost versus benefit if we only consider the net impact of best- and worst-case-scenario emissions reduction policies through 2050, which is the year it is assumed the world economy will have reached net-zero targets if all goes according to plan.
“In 2050, the year of net-zero, the best estimate of the benefits of the 1.5∘C target are about 0.5% of GDP while the costs are almost 5%.”
Of course, if the more realistic outcomes with regard to achieving emissions reduction targets eventuate, and if the global warming on tap for failing to achieve these targets is not as exaggeratedly hot as models assume (e.g., 5°C warming by 2100), the net costs of climate “action” exceed the benefits of avoided warming two-, three- and even four-fold.
Simply put, the “Paris targets do not pass the cost-benefit test.”