By Tseming Yang
With the climate negotiations in Paris at an end, the new international agreement fundamentally restructures the relationships among the parties that participated in the talks. The world should now make significant progress toward preventing the worst effects of climate change while also advancing U.S. energy and climate policy.
Media attention has primarily focused on the greenhouse gas emission (GHG) pledges put forth by countries and whether or not they are sufficient. The U.S. pledge is to reduce such emissions by 26 to 28 percent, based on 2005 levels, by 2025.
A bulk of the reduction - 17 percent - is expected to be achieved by 2020 through regulatory and policy initiatives that are ongoing, especially the Environmental Protection Agency's recently promulgated Clean Power Plan that will regulate carbon emissions from the nation's fleet of coal-fired power plants.
The rest of the reductions are expected to be achieved by 2025 through future regulatory and policy efforts.
These numbers constitute an ambitious but realistic goal. For those concerned that even this limited goal may be too much, however, there is a fallback: the pledged emission reductions will not be binding.
What has the United States gotten out of its emission-reduction pledge? Other countries have reciprocated with their own emission-limitation pledges, which combined will aim to keep global warming below the danger threshold of 2 degrees centigrade.
For example, the European Union has committed to a 40 percent reduction from 1990 levels by 2030, while China plans to peak its GHG emissions by 2030, simultaneously lowering its economy's carbon intensity by 60 to 65 percent compared with 2005.
America's future generations and economy are among the obvious beneficiaries of these efforts. Moreover, these commitments will also help to level the global economic playing field, beginning to subject all businesses across the world, not just in the United States and other developed nations, to climate regulations.
There is one further important outcome - the restructuring of participation in emission reduction that has resulted from the process.
Designed like a "pay what you can afford" restaurant, countries have been allowed to tailor their emission-reduction pledges to fit their individual national circumstances and capabilities.
Of course, the nonbinding nature of these pledges has been criticized as making them meaningless and drawn comparisons to the failed "pledge and review" process of the original 1992 climate-change treaty.
Nevertheless, the process has been valuable in allowing Paris negotiators to hit the reset button on the developed vs. developing country classification that has haunted U.N. climate efforts.
The classification was originally intended to ensure that the wealthiest countries would do the most to reduce emissions - simply because they were responsible for the bulk of the human-origin carbon emissions accumulated in the atmosphere.
While historical responsibility for climate change clearly needs to be addressed, the past two climate agreements in 1992 and 1997 chose to do so by requiring only developed economies to limit GHG emissions.
Yet, as emissions from the developing world have been rising rapidly and China has emerged as the world's greatest GHG emitter, such an approach is no longer workable.
Any climate agreement is unlikely to succeed without the substantive participation of all of the world's largest GHG emitters, regardless of developed or developing classification. Abandoning that classification and looking for alternative paths to climate equity are the key accomplishments of this conference.
Tseming Yang is a professor of law at Santa Clara University School of Law and a former deputy general counsel of the U.S. Environmental Protection Agency.