by As effective global climate action becomes ever more urgent, a “one-of-a-kind” analysis has identified policies around the world that have done the most to curb planet-warming pollution – with some surprising results.
Researchers from several European climate institutes analyzed the effectiveness of 1,500 climate policies across 41 countries over the past twenty years, in a study published Thursday in the journal Science.
They found just 63 “success stories” — stand-alone policies or combinations that achieved major reductions in climate pollution. While the relatively small number may be “sobering”, the researchers said in a statement, the results provide a blueprint for what works.
The researchers sifted through massive amounts of climate data to find countries with significant pollution declines — average reductions of 19% — in their construction, electricity, industry and transport sectors between 1998 and 2022. They then mapped these against the policy introduced by those countries. or strengthen during the same period.
“We basically do the opposite of what other people have done,” said Nicolas Koch, an environmental economist at the Mercator Research Institute for Global Communities and Climate Change in Germany, and lead author of the study. “We first look at the effects (of climate pollution), and then we try to explain the effects with policies.”
Some of the results were unexpected, Koch told CNN.
When it came to popular climate policies, such as bans on new coal-fired power plants or gas-guzzling cars, “it’s really surprising that we don’t feel that these policy tools will lead to significant reductions in emissions.” by themselves,” he said. said.
That’s not to say they shouldn’t be implemented, Koch added, but that they must be accompanied by other measures, such as taxes or price incentives.
Bans alone “are not credible if the plan is phased out right out there,” Koch said. But if policymakers also introduce additional measures — a ban on gas-powered cars plus climate tax on fuel — then it becomes more credible and changes the expectations of investors and consumers, he said.
Combinations of policies, rather than stand-alone policies, had the greatest level of success, according to the study.
For example, planet-warming pollution in the United States from its transportation sector fell significantly after the 2008 financial crisis. This was due to a combination of tax breaks for low-carbon vehicles as well as reform of fuel efficiency standards, the study found.
“That combination became effective…so this is good news for the US,” Koch said.
It’s a Democratic model to replicate on steroids in 2022 when they passed the climate law President Joe Biden; combining a huge number of tax breaks for electric vehicles, solar panels and energy-efficient home appliances, along with federal rules to reduce emissions from the most polluting sectors: natural gas and oil, transportation and power generation.
The UK made major reductions in planet-warming pollution from electricity in 2015 and 2016 following a coal phase-out plan, a minimum carbon price for UK power producers, stricter air pollution standards and subsidies for renewable energy.
It could be argued that the policy that has shown the greatest climate impacts when implemented alone is one of the least socially popular: taxation.
But a carbon tax can be complemented by more socially acceptable policies, Koch said, to ensure the burden doesn’t fall on those least able to bear it.
Carbon taxes are unpopular in the US Congress, but several bills have been introduced that would implement a “carbon border adjustment tax” that would tax imported products based on the amount of pollution they emit in the country where they were created. Those bills are seen as a response to a similar EU measure passed last year.
The policies that work best vary in different countries and sectors and further research is needed to better understand how to design climate policy mixes that work in specific contexts, Koch said.
“This is the most sophisticated study to date,” said Michael Grubb, professor of international energy and climate change at University College London, who was not involved in the research. “It is an important step forward in the analysis of ‘what works’,” he said.
However, he said the focus on big emissions cuts “means they miss the impact of thousands of smaller efforts around the world.”
Hanna Fekete, co-founder of the NewClimate Institute who was also not involved in the research, said the study provides yet more evidence that “current climate action is not enough.”
Even if the most successful policies implemented so far were scaled up to a global level, it would still not close the gap between where emissions are going and where they need to be to keep catastrophic warming at bay , she said.
She called on countries to develop a clear vision of where they want to be in 30 or 40 years, “and then actually implement policies today and create them for the future”.
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