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This report contains a correction.

See also: “Interactive: A 100 Percent Clean Future”

See also: “Fact Sheet: A 100 Percent Clean Future”

See also: “State Fact Sheet: A 100 Percent Clean Future”

Climate change is the greatest challenge facing the United States—and the world—over the next decade and beyond. The impacts of climate change have already been deadly: More than 3,000 Americans have died in weather- and climate-related disasters in the past two years.¹ Public health experts warn that climate change threatens the quality of America’s air and water.² Natural disasters have cost the United States more than $450 billion in the past three years and are projected to cost $54 trillion globally by 2040.³ By the end of the century, crop damage, lost labor, and extreme weather threaten to shrink the U.S. economy by as much as 10 percent, or $500 billion—almost double the cost of the 2009 Great Recession.⁴ The U.S. military warns that climate change will multiply the national security threats facing the country. Climate change is a crisis that touches every element of our society. It exacerbates systemic economic and racial inequality and simultaneously threatens public health; national security; the safety and well-being of communities; and the strength of the economy.

A year ago, in October 2018, the issue took on new urgency when the Intergovernmental Panel on Climate Change (IPCC) issued a stark appraisal of the latest climate science: Humanity has only three decades to completely reinvent the global economy in order to eliminate net greenhouse gas pollution and hold global warming to 1.5 degrees Celsius above preindustrial levels.⁵ The differences between the previous target of 2 degrees and the new target of 1.5 degrees of global warming are startling, including greater harm to food and water supplies; major and potentially irreversible loss of ecosystems, such as the world’s fragile coral reefs; a higher rate of sea level rise; and irreparable loss or collapse of ice sheets in Antarctica and Greenland.⁶ Every year of continued emissions raises the peak temperatures that carbon pollution will inflict, threatening destruction that can never be undone.

As the IPCC special report warned, the sheer scale of the challenge now facing the world has no precedent in all of human history. To meet this challenge, the president must organize the whole of government, and Congress must break through deeply entrenched gridlock to enact and execute a sweeping program of legislation. The United States has faced and overcome challenges that, at the time, were unprecedented, including working as a nation to go to the moon, electrifying rural America, and eradicating smallpox. The United States can and must address this crisis by putting people to work; building the necessary infrastructure to overcome the threat; and confronting the economic, racial, social injustices and inequalities that persist today.

Success is within reach, and it’s now possible to visualize a 100 Percent Clean Future. The American public is demanding action, and it’s time for political leaders to summon the courage to act. While the Trump administration has dismantled nearly all federal climate policy, state leadership has risen to the challenge with innovative and ambitious new policies. The combination of the following three pillars—100 percent clean, worker-focused, and environmental justice—should serve as a model for federal action, building on the initial efforts at the state level.

• A 100 percent clean target. Nine states across the country, along with the District of Columbia and Puerto Rico, have enacted policies to move toward a 100 Percent Clean Future by 2050 or earlier, including through clean electricity standards and aggressive economywide emission reduction targets.⁷
• A worker-focused approach. Many states have included initial plans for a worker-centered transition that would ensure the jobs necessary to build a clean future are good paying and high quality.
• An environmental justice commitment. Some states have also taken preliminary steps to develop policies that would advance environmental justice, including by identifying and cutting disproportionately high levels of toxic pollution in economically disadvantaged communities and communities of color.

It will take a combination of strong coalitions and knowledge from environmental justice experts, community advocates, labor partners, and others beyond the climate community to develop an innovative and equitable policy approach for major climate action that includes putting people to work, reducing pollution, and building healthy communities today—not just in the future. The coalitions to develop and support this ambitious policy approach have begun to organize. However, this is uncharted territory for many and will require a promise to see beyond historical differences in order to believe that progress is both possible and essential to solving the problems of today and tomorrow. Many of the candidates in the 2020 presidential election have framed their ambitious goals for climate action in a similar way.

While this initial progress is commendable, much more work remains to be done, especially to guarantee pollution reductions in economically disadvantaged communities and communities of color and to address the cumulative and deadly impacts of the history of pollution sources concentrated in these communities. Policy must take a comprehensive approach, including supporting access to affordable electricity, clean water, and good jobs in every community.

In this report, the Center for American Progress presents a framework for building a 100 Percent Clean Future that delivers on the goal of net-zero greenhouse emissions economywide by 2050 and net negative emissions thereafter to limit global warming to 1.5 degrees Celsius above preindustrial levels. This report outlines not only the policies that are needed to cut greenhouse gas emissions but also the coalitions and principles that will make them a reality. To accomplish this transition as quickly as the science demands, the report calls for strong economywide targets, sets sector-by-sector benchmarks for success, estimates the emission reductions these would deliver, and discusses how to spur the rest of the world to follow along. This report is divided into two parts:

• Part 1 discusses the coalitions and principles needed to enact enduring and effective federal climate policy. These conclusions are drawn from a review of the Trump administration’s reversal of federal climate policy, the increasing clarity of scientific warnings, and the recent success of ambitious state climate policy. In particular, the report highlights the successful model of 100 percent clean targets, a worker-focused approach, and efforts to begin repairing environmental injustice.

• Part 2 recommends a sustained, concerted, and urgent policy program. This program aims to reduce greenhouse gas emissions by at least 43 percent below 2005 levels by 2030 and to reach net-zero greenhouse gas emissions no later than 2050, consistent with the requirements identified by the IPCC report on 1.5 degrees Celsius. The report makes policy recommendations for international, economywide, and sector-specific action, proposing specific benchmarks within each sector of the economy and quantifying the emission reductions these would deliver.

In Part 1, CAP discusses the coalitions and principles needed to enact federal climate policy by outlining how the IPCC special report on 1.5 degrees Celsius has set a new goal of net-zero by 2050; proposing principles for federal climate policy to achieve this goal; reviewing models of climate policy success among the states; and summarizing an emerging consensus for federal action.

Throughout President Barack Obama’s terms in office, the United States led the rest of the world in aiming to limit global warming to 2 degrees Celsius above preindustrial levels. In this period, the United States made great strides; emissions fell 13 percent from 2005 to 2017 at the same time as the economy grew 21 percent.^{8 9} Policy drove down the cost of renewables, and deployment surged. The 2015 Paris agreement brought the world together to commit to nationally established emission reduction targets by all countries for the first time—a target that would be strengthened over the course of continued discussions to stabilize global temperatures.¹⁰ By the end of the Obama administration, the United States had prepared plans to reduce emissions by more than 80 percent below 2005 levels by 2050, consistent with a target of capping warming at 2 degrees Celsius. Though the country needed to be moving even faster at that point, it was moving in the right direction.

Today, at a time when the United States should be accelerating its efforts to limit warming, the Trump administration has returned the country to a pathway of increasing emissions. After falling for three consecutive years, U.S. greenhouse gas emissions rose by over 3 percent in 2018.¹¹ The United States is now likely to miss its Paris pledge to cut emissions 26 percent to 28 percent below 2005 levels by 2025¹², as seen in Figure 1.

By 2018, the Trump administration’s alarming reversals of climate policy had already made it apparent that restoring the country’s previous momentum toward the Paris agreement’s goals of “well below” 2 degrees Celsius of global warming would be a challenge. That challenge gained new urgency in October 2018 with the publication of the special report on 1.5 degrees Celsius from the IPCC.²⁵ This report brought into sharp focus the conclusion that 2 degrees of global warming is no longer an acceptable threshold.

The special report summarized the world’s leading research on what will happen if the world continues to push global warming from the current 1 degree Celsius up by even just another half a degree, to 1.5 degrees Celsius above preindustrial levels. The differences between 1.5 degrees and 2 degrees Celsius of global warming are startling, including greater harm to the world’s food and water supplies; major and potentially irreversible loss of ecosystems such as the world’s fragile coral reefs; a higher rate of sea level rise; and irreparable loss or collapse of ice sheets in Antarctica and Greenland.²⁶ One of the most alarming differences is that failing to bring temperatures back down to 1.5 degrees Celsius this century would, in most projections, mean the world will still be warming in 2100, with untold consequences.²⁷

Stabilizing global temperatures at 1.5 degrees Celsius of warming is possible, but the IPCC report’s authors warn that the scale of this transformation has “no documented historic precedent,” requires “rapid and far-reaching transitions,” and implies “deep emissions reductions in all sectors”.²⁸ This amounts to a global call to action in perhaps the strongest terms employed by the scientific community to date.

The conclusions of the special report define a new target. To bring the current global warming trajectory back down to 1.5 degrees Celsius by the end of the century, global carbon dioxide emissions must fall 40 percent to 60 percent below 2010 levels by 2030; reach net-zero by 2050; and be net negative thereafter. The IPCC also noted that non-CO2 emissions, such as methane, need to be steeply reduced, though they may not reach net-zero globally.

To meet this target requires a significant acceleration in required emissions reductions, as the previous goal of 2 degrees Celsius meant only a 25 percent reduction in carbon dioxide emissions by 2030 and net-zero emissions only by 2070.²⁹ To put this in perspective, in 2009, at the start of President Obama’s first term, the world would have had about 60 years to eliminate an annual emission rate of 48 billion tons of carbon dioxide-equivalent to stay below 2 degrees Celsius this century.³⁰ In 2021, at the start of the next presidential term, the world will only have about 30 years to eliminate an annual emission rate expected to have edged up from the current 53 billion tons if we are to return to 1.5 degrees Celsius.³¹ That is more than double the annual pace of reduction.

Bold new thinking and action is required if the world is to keep up with the targets set by the scientific community. After years of development, many policies and technologies are ready for immediate deployment, but no one yet has all the answers about how to accomplish a complete and timely transition. This is especially true when it comes to negative emission technologies, forecasting the threats to natural carbon sinks, and developing technologies for hard-to-decarbonize sectors such as manufacturing, all of which are areas where innovation is needed. When it comes to scientific research, technology deployment, infrastructure investment, and so much more, there is no time to spare in getting the country onto a path toward net-zero emissions.

Setting a target for greenhouse gas emission reductions is an act of leadership that relies on consideration of a combination of policy principles, available models, data, and feasibility. Failing to set a sufficiently ambitious interim target would fail to inspire the scope of changes needed, necessitate ever steeper reductions in later years, and magnify the damages of climate change. No target will be effective, however, if it pushes emissions-intensive agriculture and industry overseas (harming both the U.S. economy and global emissions) or provokes a political backlash that reverses policy changes.

People of all communities need to see the benefits of climate action in their own lives and have a voice in shaping their future. Those benefits extend beyond just the avoided disruption of climate change to include good jobs, clean water, and justice for the communities of color, tribal communities, and low-income communities that have lived with the cumulative impacts of decades of toxic pollution. As state-level and international examples illustrate, failing to center policy on the needs of workers and communities will undermine popular support for climate action, may even create backlash, and ultimately slow progress toward net-zero emissions.

For this report, the Center for American Progress synthesizes existing literature and modeling and evaluates the combined effect of various policies against a target of at least a 43 percent⁴⁶ reduction below 2005 levels in greenhouse gas emissions by 2030 and net-zero emissions no later than 2050. This is based on the interquartile range for cutting carbon dioxide emissions identified by the IPCC report on 1.5 degrees Celsius, restating the equivalent reduction against 2005 levels rather than 2010 levels, and also adding in all other greenhouse gas emissions.

The 2030 and 2050 targets identified in this report are extraordinarily ambitious, requiring reduction of emissions at a rate that is four times faster than the annual rate of reductions achieved between 2005 and 2017.⁴⁷ Achieving these targets will require a new set of policy principles. These are the 10 principles that underpin CAP’s recommendations:

1. The goal is net-zero economywide emissions no later than 2050. Stabilizing global warming will require achieving net-zero greenhouse gas emissions no later than 2050 and net-negative emissions thereafter. This is what is meant by a 100 Percent Clean Future, and it marks a profound shift in thinking. The United States and other countries need to avoid infrastructure and technologies that lock in fossil fuel dependency beyond 2050 except where carbon capture and sequestration is viable and necessary. In parallel to emission reductions, the rapid development and deployment of negative emission technologies must begin now to supplement earth’s natural carbon sinks and pull historical greenhouse gas emissions back out of the atmosphere and oceans.
2. Interim emissions goals must be ambitious, achievable, and effective. Interim emission reductions must put the country on the path to net-zero emissions by 2050 in a way that is politically durable and that creates a model for success that other countries will adopt. This report proposes cutting U.S. emissions at least 43 percent by 2030, which is the floor for action identified by the IPCC report on 1.5 degrees Celsius. Such an aggressive 10-year timetable means climate action must be the top priority for a new administration’s legislative and executive agendas.
3. Climate action must put people first. Building a 100 Percent Clean Future will create millions of new jobs, and policy must ensure that these jobs are located here in the United States and provide workers fair wages, good benefits, and a voice on the job. Workers and communities must be at the table in developing and implementing climate change solutions. Any plan must