On Oct. 31, world leaders will gather at the 26th United Nations Climate Change Conference of the Parties (COP26) to explore ambitious new targets for cutting greenhouse gas emissions and putting the world on a path to net-zero emissions by 2050. We sat down with National Academy of Sciences President Marcia McNutt to discuss how science can help inform these efforts.

Q: Science has always been the basis for every United Nations conference on climate change. As COP26 draws near, and after decades of research, what does climate science tell us about the current state of our planet?

McNutt: Since the beginning of [the COP conferences], scientific predictions have improved and become more comprehensive about what sort of future we’re making for ourselves with the continued release of greenhouse gases. If we go back to the Charney report [a landmark 1979 National Academies study chaired by meteorologist Jule Charney] — it first raised the alarm and predicted that with the doubling of CO2, the average global surface temperature would rise by 3 degrees Celsius, plus or minus 1.5 degrees.

Now, scientists have moved beyond this remarkably prescient prediction to understanding more specifically the consequences that accompany that change in average global temperatures. For example, we’re seeing more extremes — more extreme hurricanes with greater intensity, more rainfall, and more frequent droughts, along with melting glaciers, which already threatens the water supply of many communities, particularly in the Himalayas. We’ve also seen changes in the biosphere that have come from these changes in temperature. We’ve seen difficulties in adaptation, we’ve seen what we call mismatches in phenology, where animals are migrating on their normal schedule based on the sun, but because of temperature [changes], the food that they need along their migration path has already come and gone by the time they get there. So, you know, sometimes we just hate it when scientists are that right. In this case, the predictions have proved to be fairly accurate, and if anything, too conservative.

Q: An overarching goal of COP26 is to secure net-zero global emissions of greenhouse gases by 2050 and keep warming to 1.5 degrees Celsius above pre-industrial levels. Why is that such an important target to aim for?

McNutt: If we exceed this [global mean temperature limit], it could produce huge and perhaps untenable changes to the situation on Earth — in terms of things like the amount of and rate of sea level rise, and the disruptions to climate zones — that require adaptation beyond what we think humans can tolerate. So, for example, if we look back at the history of the rise of civilization, it occurred when [our climate became stable]. That’s when people put down roots. They built cities, and they developed agriculture. Before that, humans were nomads who could freely roam the Earth and retreat from rising sea levels as they needed to.

And now that’s all in danger, because we have disrupted that stable state that’s existed for thousands of years. And obviously, we cannot go back to being nomads. In fact, we’ve already seen the political disruption as climate refugees try to move from places that are no longer suitable for growing crops, because of drought, or because of heat.

We can see pretty clearly what the future looks like if radical action is not taken to transform our energy infrastructure, to change our land use, to preserve our forests and carbon sequestering spaces. And really, we can’t wait any longer.

Q: Do you think the goals of COP26 are achievable?

McNutt: I was trying to think of a time when the planet took collective action successfully. And [one case is] nuclear disarmament. We were marching in lockstep — the major leading nations around the Earth — toward nuclear annihilation, and we walked back from the cliff. And so we know that when the fear is great enough, the nations of the world can band together to prevent what is not in their mutual interest.

However, the control of the nuclear arsenal was in the hands of basically a few leaders. Global climate change is going to require much more collective action. Most governments see that they have to work with other countries, if we’re going to prevent the worst consequences from climate change. It’s not an issue where nations feel they have to compete with each other. If anything, there’s lots of encouragement to cooperate. It also requires ordinary citizens to make decisions that are in the best interests of people they don’t even know. And that’s why it’s hard. Without citizens, and corporations, and other institutions rising up, any progress could be very fleeting.

Q: Of course, COP26 is taking place as much of the world is still struggling with the COVID-19 pandemic. Are there any lessons that stand out from U.S. and global pandemic response that could inform efforts to confront climate change?

McNutt: I think the pandemic has taught us that we can turn on a dime if we need to. When this country shut down, people stopped commuting, they immediately stopped flying in airplanes, and CO2 emissions went down. And for the most part, we came through the pandemic without traveling, and it changed lives for many people.

The other thing we’ve learned is how all of the best work of scientists can be undone through misinformation. Scientists in record time came up with vaccines that, had everyone in the U.S. stepped forward and taken them as soon as they were eligible, we could have stopped this pandemic in its tracks. And yet misinformation prevented us from achieving this goal in a short time period.

I think some of the things the National Academies have done to reach the general public are actually the most important, because we are a trusted voice. I think we need to do more of that and seek more opportunities to get those messages out. For example, Based on Science has a component aimed at trying to debunk some of the myths out there about climate change. And one of our most effective reports was Climate Change: Evidence and Causes, a publication we did with the Royal Society in the U.K. It is geared for a popular audience and explains clearly — What are the things we know about climate change? What are the things that are still uncertain?

Q: The National Academies have long been a leader in advancing climate change science and in putting climate change on the national and global agenda. As science, and more broadly the research enterprise, are developing solutions, what role can the Academies play in taking on this challenge?

McNutt: The Academies have already done a lot to advance solutions. I believe we’ve written more reports on climate change — climate change mitigation, adaption, impacts, and most recently, reports on sensibly decarbonizing the U.S. economy and reimagining the future of electric power — than just about any other single topic. And increasingly, we’re doing our work across disciplines. We can easily pull from the life sciences, the physical sciences, biomedical sciences, engineering, and infrastructure, as well as social, behavioral, and economic sciences.

I also think there is this fear out there that acknowledgement of climate change means that people will have to wildly change their quality of life. But the truth is, we have solutions in hand that will continue to provide the energy we need without releasing the CO2. We just need to get that message out. We’re not talking about taking away the things that bring you joy in life. We’re just talking about substitutions. They’re not necessarily all easy, but they are becoming more available.

For example, to make [hybrid or electric vehicles] truly practical on a massive scale, we need … a whole network of charging stations. The speed for recharging is getting faster and faster while the miles traveled are getting farther before you have to recharge. So solutions like that are on the horizon. And the transportation sector is the No. 1 largest contributor to greenhouse gas emissions.

Q: As the nation and the world take action to decarbonize the economy and adapt to impacts of climate change, what role can science play in reducing the burdens on poor and marginalized communities and ensuring that the solutions to climate change are equitable and beneficial to everyone?

McNutt: We know that climate change affects the most vulnerable among us the most ... and these are the people who feel they have the least economic clout, the least political clout, the least social capital. One thing that the Academies could do is [explore] some ways that … financial incentives could work with public policy in a way that doesn’t leave groups behind. For example, tax credits for homeowners who install solar panels, or for electric cars, work well for people who own homes or who are earning lots of money. But if you’re a renter or not paying taxes because you’re earning a low income, that’s no incentive at all. So, we have to find … a menu of ways to get people who have resources to do the right thing, but also make sure that we don’t leave behind the people who don’t have the resources.

Q: What about inequities between rich and poor nations as they tackle climate change?

McNutt: [For a long time] developing nations have not been part of the problem — their per capita energy use and CO2 emissions are often trivial compared to that of the developed world. And yet they are aspiring to a better quality of life. The developing world has a challenge because the infrastructure and tools that we can use in the first world to reduce our CO2 emissions are not necessarily as readily adapted to the developing nations.

But I was really happy to see [strategies] that banks are using when they invest in the developing world, and that nations are using when they invest — to make sure that, for example, China stops the construction of coal-fired power plants. These developing nations can go immediately to renewable sources, and leapfrog over the mistakes we made, which in the long run will be much better for them.

Q: As we simultaneously fight the pandemic and confront the climate crisis, many people, especially many young people, are understandably feeling pretty pessimistic about the state of the world. What would you say to encourage them and inspire optimism about the future?

McNutt: When I was in high school, those were the years of Woodstock. The month before I graduated from high school, the massacre occurred at Kent State. Students rose up in total fury about what was happening in Southeast Asia, and how this was a horrible direction for the country. And they were heard. This was the same time that Earth Day began. These students … helped change this nation. This was when the Clean Air Act and the Clean Water Act were passed. So my message to young people is: Don’t stop standing up when you see things that aren’t right. There are many people of my generation who will support you.

Consensus Study Reports

• Accelerating Decarbonization of the U.S. Energy System (2021)

• The Future of Electric Power in the United States (2021)

• Reflecting Sunlight: Recommendations for Solar Geoengineering Research and Research Governance (2021)

• Negative Emissions Technologies and Reliable Sequestration  (2018)

• Attribution of Extreme Weather Events in the Context of Climate Change (2016)

Other Resources

• Climate Resources at the National Academies — Features upcoming events and new resources

• Climate Change: Evidence and Causes — Succinctly summarizes the science that shows climate change is caused by human activity

• Based on Science — Captures common science questions, and answers them using research and input from experts (Climate questions include: Does global warming contribute to extreme weather? Are humans causing global warming?)

• Decarbonizing the U.S. Health Sector — A new action collaborative from the National Academy of Medicine that will address the health sector’s environmental impact and strengthen its sustainability and resilience to climate change