Last month, Rep. Alexandria Ocasio-Cortez and Sen. Ed Markey introduced a joint resolution calling for a Green New Deal. The debate about the sweeping nature of the policy and its implementation costs has largely ignored calculations of the benefits of avoiding future climate change. New science suggests that these benefits are likely to be enormous.

Climate change is a complex challenge, and solving it will require substantial investment. But when deciding whether to make the investment, it doesn’t make sense to only consider the costs; the real question is whether the benefits yield a worthwhile investment. And when the stakes are high, finding an effective solution becomes even more valuable.

Imagine that a loved one is diagnosed with a serious illness that requires expensive treatment. Most of us would try to find a way to obtain the treatment, because our loved ones’ health is so important. Policy makers must make similar decisions about the costs and benefits of possible policy actions.

The Green New Deal represents one possible approach to addressing the climate challenge. It is an ambitious set of goals that includes direct climate mitigation and adaptation actions like reaching zero-emissions from the power sector in the next 10 years. And it also sets out a broader set of goals like ensuring high-quality health care, affordable housing and economic security, as well as a series of mechanisms such as ensuring the rights of workers to unionize and of businesses to be free from monopolies and unfair competition.

Much of the debate since the unveiling has centered on whether it is politically wise to mix the more narrow climate-focused actions with the broader social and economic goals. However, given the scale of the climate-focused actions, it is critical to carefully and rigorously evaluate whether the costs of those actions—such as decarbonizing the electricity sector, or retrofitting all existing buildings in the country—are worth the benefits that they will generate. 

Fortunately, scientists have made enormous progress in quantifying the potential impacts of global warming on different aspects of the economy and society. That work has produced three findings that can be used to evaluate whether the climate actions in the Green New Deal are likely to be worthwhile investments.

First, there is very strong evidence that continuing on the “business as usual” trajectory will create a drag on global economic growth, costing the world trillions of dollars. The United States is not immune to these economic effects. On the contrary, achieving the emissions reductions outlined in the Paris Agreement is likely to save the United States several trillion dollars (in today’s dollars), relative to continuing on the business as usual trajectory.

Second, we can expect continued global warming to exacerbate income inequality in the U.S. This is partly because poor and marginalized communities are more vulnerable to the impacts of extreme events and other climate stresses. In addition, new research shows that economic impacts will not be uniform, with poor counties in the U.S. experiencing economic losses that are approximately three times as large as rich counties.

Third, curbing climate change will avoid a host of other damages that are not directly reflected in economic growth. These include the increasing risks of extreme events such as heat waves, heavy rainfall and storm surge flooding that we know are already intensifying as a result of global warming. They also include other emerging impacts such as ocean acidification, larger and more intense wildfires, interpersonal violence, and self-harm.

Research over the past decade has also identified a number of additional benefits from climate-related actions. For example, California recently issued a climate-safe infrastructure plan that will help the state simultaneously upgrade its infrastructure and reduce damages from climate change. Likewise, meeting the greenhouse gas reductions outlined in the Paris Agreement would also avoid tens of millions of air-pollution-related deaths worldwide, mostly in the next few decades. And the Clean Power Plan—which the Trump administration has pledged to roll back—would have saved thousands of lives and tens billions of dollars in the United States by 2030.

Debating the outcomes and investments envisioned in the Green New Deal is a task for Congress, presidential candidates and the voters. As that debate takes place, it should be grounded in our best knowledge of the costs and benefits of avoiding further climate change. While the climate-related actions envisioned by the Green New Deal will require investment, our best evidence suggests that the benefits are likely to substantially outweigh the costs.