Even ardent supporters acknowledge that the Paris treaty by itself will do little to rein in global warming. The United Nations estimates that if every country were to make every single promised carbon cut between 2016 and 2030 to the fullest extent and there was no cheating, carbon dioxide emissions would still be cut by only one-hundredth of what is needed to keep temperature rises below 3.6 degrees Fahrenheit. The Paris treaty's 2016-2030 pledges would reduce temperature rises around 0.09 degrees Fahrenheit by the end of the century. If maintained throughout the rest of the century, temperature rises would be cut by 0.31 degrees Fahrenheit.
At the same time, these promises will be costly. Trying to cut carbon dioxide, even with an efficient tax, makes cheap energy more expensive — and this slows economic growth.
My calculations using the best peer-reviewed economic models show the cost of the Paris promises — through slower gross domestic product growth from higher energy costs — would reach $1 trillion to $2 trillion every year from 2030. U.S. vows alone — to cut greenhouse-gas emissions 26 percent to 28 percent below 2005 levels by 2025 — would reduce GDP by more than $150 billion annually.
So Trump's promise to dump Paris will matter very little to temperature rises, and it will stop the pursuit of an expensive dead end.
Paris was a well-meaning — if flawed — attempt to address a genuine global issue. With no international climate policies at all, it is probable that we would see a temperature rise of perhaps 7 degrees Fahrenheit by the end of the century. The United States needs to find a smarter solution. Climate economists have found that green energy R&D investment would be a much more efficient approach.
This is very much in line with Trump's campaign promise of “investment in research and development across the broad landscape of academia” and with its suggestion that we could develop “energy sources and power production that alleviates the need for dependence on fossil fuels.”
This investment in U.S. ingenuity could help innovate the price of green energy down below fossil fuels. Only then will we truly be able to stop climate change.
Statements by Trump's campaign also indicate that the next administration will create a global development and aid policy that recognizes that climate is one problem among many.
Asked about global warming, the campaign responded, “Perhaps the best use of our limited financial resources should be in dealing with making sure that every person in the world has clean water. Perhaps we should focus on eliminating lingering diseases around the world like malaria. Perhaps we should focus on efforts to increase food production to keep pace with an ever-growing world population.”
This would be a big change. The Organization for Economic Co-operation and Development analyzed almost all aid from the United States and other rich nations and found that about one-third is climate-related aid.
This is immoral when 2 billion people suffer from malnutrition, around 700 million live in extreme poverty and 2.4 billion are without clean drinking water and sanitation. These problems can be tackled effectively today, helping many more people more dramatically than “climate aid” could.
Despite its length, and for all of its heat and bluster, the election campaign left many unanswered questions and understandable concerns about the president-elect's positions on climate change, aid and development.
But, surprisingly, there is now an opportunity. To seize it, the Trump administration needs to go beyond just dumping the ineffective Paris agreement, to an innovation-based green energy approach that will harness U.S. ingenuity. Such a policy could mean a real solution to climate change and help the world's worst-off more effectively.