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When the Trump administration gave notice that the U.S. would drop out of the Paris Climate Agreement, it said it was doing so because it was a bad deal for the country. This view is wrongheaded. The science is unequivocal. Global warming is real, human induced and, if unabated, it poses catastrophic risks to all inhabitants of the planet.

Limiting this threat requires a global effort, but that effort is currently hampered by the absence of the U.S. as a major world power and second largest source of greenhouse gases (and leader in terms of historical CO2 emissions). It is in our national interest, as well as the right thing to do, not just to contribute to the global effort, but also to take an active role in its evolution.

To believe otherwise belies the nature of the threat and what it will take to manage it: The total of global emissions of greenhouse gases must be eliminated, and all the nations of the world are contributing to it. Therefore, reducing the domestic threat will require universal action, and inaction by the U.S. encourages free riding by others. If we are not doing our part, why should they?

How much will continuing delay cost? The National Oceanographic and Atmospheric Administration (NOAA) has kept careful track of extreme climate events over the past four decades. Damages thus far come to trillions of dollars; and they are growing. But these include only part of the picture, what is referred to as “market” damages – expenditures that show up in national income accounts as a result of hurricanes, heatwaves, wildfires, severe storms, floods, and droughts.

Even more worrisome, though, are “non-market” impacts such as mortality and morbidity where assigning a dollar value is much more difficult and contentious. Also included in this category are losses in environmental quality and biodiversity and loss of ecosystems upon which our future prosperity depends.

Taken all together, the risks are, indeed, frightening. And what we have experienced so far are likely only a forewarning of worse to come as ice sheets melt, forests weaken and decline, permafrost thaws releasing carbon, and sea level rises. By any measure, the stakes are extraordinarily high.

So, what should our political leaders do to meet their obligations to protect the health, safety, and welfare of the country? No doubt much effort will be required to re-establish international trust and leadership so recklessly discarded over the past nearly four years, but three steps are necessary if we are to rejoin the global effort to meet the climate challenge.

Step 1 will require immediately signaling other nations that we are ready to resume our role in the global climate effort by rejoining the Paris Climate Agreement. Adopting emission reduction goals and implementing actions to meet them, comparable to those already under way among other wealthy participants, will be an essential part of this step. These commitments need to look beyond the initial 2030 focus of the Paris agreement to establish firm policies for longer-term emissions reduction. Also, thought needs to be given to preventing future administrations from arbitrarily and capriciously reversing course.

Anyone concerned that the costs of achieving a non-carbon economy are too high need only study the consequences of not doing so. The investment will be a bargain, which is not to imply that eliminating U.S. emissions will be costless. The transition will necessitate early retirement of existing power plants and equipment that, but for their contribution to global warming, would have years of remaining life-time. The costs of replacement will not be insignificant, but in the long term the reduction in damages will justify the investment.

The question is how to achieve such an outcome. The first round of industrialization was powered by fossil fuels, then an “inexpensive” and plentiful source of energy. Only later did the full costs become apparent. Future technology choices must reflect the true costs of energy, not only to the economy but also to public health and wellbeing. Recognizing costs – both market and non-market – that are currently excluded from the calculus will help to tilt technology choice decisions in the optimum direction.

Step 2¬†Figure 1 shows that the U.S., with 4% of the world’s population, is responsible for approximately 15% of global CO2 emissions. China and many other industrialized countries have pledged dramatic emission reductions by mid-century. The intentions of many lesser developed countries, aspiring to a lifestyle akin to their wealthier neighbors, are less well defined. If these countries opt for development paths powered by fossil fuels, emission control efforts of industrialized countries will not stop the warming. Total global emissions could stay roughly the same; only their geographical origins would change.

World co2 emissions graphic

Incentivizing developing countries to forgo carbon-polluting technologies in the end will be a heavy lift. Without a clear commitment to re-engage in the effort to halt global warming, and stick to it, the U.S. will be in a weak position to persuade other nations to reduce their emissions. In addition to moral and political support, developing countries will need technical and financial assistance.

Technology development and transfer, then, is one area where the U.S. can help developing nations choose a low-carbon development path, with the U.S. providing technical expertise and funding support. Moreover, active involvement in these areas will open up opportunities for U.S. participation in important emerging markets.

Step 3 will involve the massive and immediate collective action required to manage the impacts of climate threats, and the U.S. focus should not be limited to emissions abatement. Nations must also deal with the pain and suffering that inhabitants of the planet are currently experiencing and that will worsen given the additional warming already baked into the system. Active contribution to these adaptation efforts is also in the U.S. national interest.

Just as greenhouse gases respect no national boundaries, neither do their impacts. If warming continues unabated, all will be subjected to its increasing damages, with the impacts most harshly felt by those least able to deal with them. Without help to address the challenge, global political stability will be at risk, leading to millions of environmental refugees and stateless people being put at great risk. Regional conflicts and humanitarian crises then could exhaust the resources of rich and poor countries alike. One can envision a domino effect spilling over vast areas of the planet.

The U.S. is at a fork in the road. We can continue to deny our responsibility for this problem, and in so doing risk a future fraught with suffering and pain. Or we can rejoin the international effort and help open the door to a brighter future. These efforts will involve not only putting our own house in order, but assisting others to do the same.

Some may derisively dismiss such efforts as merely “humane.” So be it. But rest assured they are also in our own self-interest.


Richard Richels directed climate change research at the Electric Power Research Institute (EPRI). He served as lead author for multiple chapters of the IPCC in the areas of mitigation, impacts and adaptation from 1992 through 2014. He also served on the National Assessment Synthesis Team for the first U.S. National Climate Assessment.

Henry Jacoby is the William F. Pounds Professor of Management, Emeritus, in the MIT Sloan School of Management and former co-director of the MIT Joint Program on the Science and Policy of Global Change, which is focused on the integration of the natural and social sciences and policy analysis in application to the threat of global climate.

Gary Yohe is the Huffington Foundation Professor of Economics and Environmental Studies, Emeritus, at Wesleyan University in Connecticut. He served as convening lead author for multiple chapters and the Synthesis Report for the IPCC from 1990 through 2014 and was vice-chair of the Third U.S. National Climate Assessment.


Additional posts in this series:

Inaction on the climate threat is NOT an option
– Rejoining the global fight against climate change: In the U.S.’s national interest
Vigorous action needed, and soon, on climate change
Multiple extreme climate events can combine to produce catastrophic damages
Extreme events ‘presage worse to come’ in a warming climate
The evidence is compelling on human activity as the principal cause of global warming
Evidence shows troubling warming of the planet
Key messages about climate change: an introduction to a series
Five science questions that ought to be asked at the debates

Topics: Policy & Politics