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Anna Harper: There are hundreds of authors from nearly every country in the world. The authors are from a range of scientific domains, and this year there also are authors from other fields—like economists. When we met in Paris, it was quite exciting to meet people from so many different countries and backgrounds, knowing we’ll all be working together on this over the next few years.

Talk about your research background and how it led to your work with IPCC.

My Ph.D. is in atmospheric science, but I’ve moved throughout my research career into studying how land and atmosphere interact. Ever since , my research has begun moving even more into exploring how we can use the land to help reduce climate change: How do things like planting large forests help reduce future climate change? Subsequently, how do forests respond to that?

I use Earth system models to study this and spend a lot of time looking at projections and exploring different features we might have with climate change. A big part of that is what people decide to do.

For the first time, the panel is almost evenly split between male and female scientists. What does this mean to you personally, and what does it say about the direction of scientific inquiry as a whole?

Oh, I’m really excited about that. If you look at the number of highly cited, “popular” papers in my field, it’s often led by men. More and more, however, there are women who are doing impactful science. It’s exciting to be a part of that! I think it will, hopefully, just continue to grow in the future, as women see that we definitely have a role in climate science. It’s thanks to many decades of effort and funding focused on improving representation for women in science and STEM.

Let’s discuss the specific chapter you’ll be working on: “Global projections of Earth system responses across time scales.” How will you look at climate impacts over time?

Typically, a lot of these projections look as far out as 2100 (now, as the century goes on, we honestly should be looking beyond that). One of the purposes of the IPCC is to help inform policy, and people who are writing policies really want to know about what’s happening in the next 10 or 20 years. In the report, we’re thinking about both century-scale implications as well as the next couple of decades to help inform people’s decisions. The next report will focus on different timescales: near-, mid-, and long-term changes.

What Earth systems will be most affected, and what are some surprise or seemingly unrelated impacts of climate change?

One of the most certain impacts is that, as the average temperature gets warmer, the hot extremes increase as well. This is a really big impact that people are already feeling and, unfortunately, will continue—like those heat waves, which can be really amplified in urban areas. You also see things like last year’s wildfires in Los Angeles, and these kinds of extremes are more likely the higher the temperature goes.

My research is on forests, and we don’t really know what’s going to happen with forests in the future. One interesting thing is that as we’re adding more carbon dioxide to the atmosphere, trees like carbon dioxide because it’s food for them. We’re seeing some signs of global forests doing well with extra carbon dioxide.

But heat and drought are also more likely with climate change, so there’s a point where the extra CO₂ is no longer good because it’s too hot and dry. There’s a lot of research into how forest systems, like the Amazon, will respond. There’s a lot of concern that these global forests could reach a tipping point and have a large-scale mortality event that kills off a large part of the forest. We think there’s a low likelihood of that occurring, especially if we can limit climate change and reduce deforestation, but it would be devastating.

How does the working group you’re in connect to and support the other working groups for the report?
My group, Working Group One, is about the physical basis of climate change and its impacts. Working Group Two is about the actual impacts on people and ecosystems, and how we can adapt to these changes. Working Group Three is focused on the mitigation of climate change. There are lots of ways these things interact, and there is a bigger emphasis on people working across groups and integrating knowledge in this assessment cycle.

There is a growing emphasis on the value of a cross-disciplinary look at climate science. Usually, the working groups meet separately when they have the big author meeting, but for the first time we all met at the same time in Paris.

You serve on the National Academies’ . How is AI impacting the field of climatology?

One thing I think is cool about AI is that it can make climate science more accessible to more people. Typically, if you wanted to know the impacts of climate change in your region, you might have to find someone to run a complicated climate model for you, get all the outputs, and interpret them. However, AI can build simpler models or enable them to be accessible somewhere, like a public website. I think that’s great, because it’s turning science from something almost opaque into something much more accessible.

As an educator, you also spend time with students, many of whom are passionate about climate change. How do you think this next generation will respond to this?

I try to keep the positives in mind, because I really do think there is hope, and there has been progress over the last 10 years or so. One great thing is that if you care about climate change, you no longer need to study it academically. There are so many solutions to climate change so that anyone from any part of campus can have some kind of role in the future. Education, engineering, business—everything that people are doing. There are ways you can incorporate solutions into those fields.

How has your time at UGA helped you contribute to this project?

I’m in the geography department, and I love that it’s a very multidisciplinary department. The students and faculty I work with all have different perspectives, which is what it’s like to work with the IPCC. It involves big-scale thinking, and that’s really encouraged in my department. In the couple of years I’ve been at UGA, I also feel encouraged to think beyond just my discipline about how these major issues impact humanity.

Do you have a message for a reader who is concerned about climate change? What can they do as an individual?

Keep learning. There are student groups at UGA, like the , that are thinking about climate solutions in and around Athens, which is so cool! It can be isolating if you’re just doomscrolling and learning all the negative news, so connecting with other interested people helps fight against some of that despair—and also gives you more positive options for action.