95% Consensus of Expert Economists: Cut Carbon Pollution

The Institute for Policy Integrity at the New York University (NYU) School of Law recently published a report summarizing a survey of economists with climate expertise.  The report was a follow-up and expansion of a similar survey conducted in 2009 by the same institute. The key finding: there’s a strong consensus among climate economics experts that we should put a price on carbon pollution to curb the expensive costs of climate change.

The survey participants included economists who have published papers related to climate change “in a highly ranked, peer-reviewed economics or environmental economics journal since 1994.” Overall, 365 participants completed the survey, which established the consensus of expert climate economists on a number of important questions.

Carbon pollution cuts are needed regardless of what other countries do
In the 2009 version of the survey, the respondents were asked under what conditions the United States should commit to reducing greenhouse gas emissions.  57% answered that the US should cut its emissions no matter what actions other countries take, while another 38% said that American emissions cuts would be warranted if many or all other countries commit to reducing theirs (as just happened in the Paris international negotiations).

In the 2015 survey the number of expert economists saying that the US should cut its emissions no matter what rose to 77%.  A further 18% said that if other countries agree to cut their emissions, the US should follow suit.  In other words, there is a 95% consensus among expert climate economists that the US should follow through with its pledges to cut carbon pollution in the wake of the Paris international climate negotiations, and more than three out of four agreed that the US should take action to curb global warming no matter what.

This expert consensus is in stark contrast to conservative political opposition to the Paris accord.  For example, Republican presidential candidate Marco Rubio said of the agreement,

This kind of unilateral disarmament in our economy is reckless, and it is hurting the American Dream

Quite obviously an international agreement made by 195 nations around the world is the antithesis of unilateral action.  However, 77% of expert economists agree that unilateral action would be appropriate in any case, directly contradicting Rubio’s comments.  Additionally, 82% of the experts agreed that by implementing climate policies, the US could strategically induce other countries to cut their carbon pollution.

Climate change is already hurting the global economy

When asked at what date climate change will have a net negative impact on the global economy, the median survey response was 2025.  In the recent past climate change likely had a net positive impact on the global economy, due primarily to the effect of carbon fertilization on crops and other plant life.  However, even contrarian economists agree, when accounting for the vulnerability of poorer countries to climate impacts, global warming has been hurting the global economy since about 1980.

The NYU survey asked when the economic benefits we experienced up to 1980 would be completely wiped out; 41% of respondents said that’s already happened.  Another 25% answered that it would happen within a decade, and 26% said we’d see net negative economic impacts by 2050.  If we continue with business-as-usual pollution and warming, on average the experts predicted a GDP loss of about 10% by the end of the century, and that there would be a 20% chance of a “catastrophic” loss of one-quarter of global GDP.

95% Consensus of Expert Economists:  Cut Carbon Pollution