Camille Parmesan: From passion for butterflies to climate change expertise

Girls and science: Yes, they can

Solange Cassette (SC): In an interview^[1] you stated that you have always been interested in the natural world. Speaking of butterfly research^[2] you asked, “Why is it that little girls don’t get out and investigate nature in the same way that little boys do?” In addition, for some years, in France, girls have a disaffection for scientific studies^[3]. What do you think? What advice would you give to girls who want to do scientific research in your field or more generally?

Camille Parmesan (CP): It's something that has bothered me for a long time. For whatever reasons, the kids who join the boy scouts, camp out in the woods, and do the survival courses tend to be boys. They're the ones who collect butterflies, become birders and start collections of butterflies, beetles, etc... It's much rarer for girls. I don't know where this comes from, but I think some changes can come from parents - who can encourage their girls that it is OK to be dirty, to dig around and discover new things -  to look around when you're in the forest or a meadow and discover what’s there.
 

“What advice to give to girls?” You know, I hate to tell people to collect things, because if you're in a national park, you are not supposed to collect things… So I try to think of “How do you change the pattern so that girls are more interested in what is happening in nature?”. If I think about it, the reason my mother had an interest in nature is because she grew up on a farm, with lots of open space and nature all around. Her father treated his son and daughter equally.  My mom drove the tractor from when she was 14 years old, and her father encouraged her to get a Master's degree in Geology.  I think that, very early on, getting girls to believe in themselves and not to be afraid of science is very important.
 

A special connection with butterflies

SC: Talking about your research, you explained that “You really get to know the pulse of the species you are working with and gain an intuition for them […] I think it would be very difficult to interpret the kind of work I do without having this intuition”^[1]. It seems rather strange to speak about intuition towards butterflies for example. Can you explain your thoughts?

CP: I think the general public have a misunderstanding of science. When we publish a result, there are approaches for gathering data that are considered scientifically valid and we all follow these approaches. You get a bunch of information about when a bird is singing, or when a bird arrives, or when a butterfly emerges. That is the data: you have a date, a time, etc.. But when you are then looking at the data as a whole and trying to understand what it means, that takes an understanding of the organism that you are working with, which involves intuition. I can have enormous data sets - Excel spread sheets with millions of columns and rows - but if I know nothing about the species that the data pertains to, it can be very difficult to interpret it in a way that makes sense!

EB Ford, a biologist, once said something like, “A good butterfly biologist can walk into a meadow look around, see what plants are there and what is flowering , and would know what butterflies should be in that meadow”. That is what I am trying to get across - that pooling all of that little information together in your brain and then coming up with a broad understanding of the system is as much intuition and art as it is science.

And when you miss them

SC: You said, “Basically, my heart is still as a field biologist.”^[4] Since you work a lot for the IPCC^[5], you probably had to slow down your field research on butterflies. How do you deal with this?

CP: It is very hard, I would admit. As a graduate student, I spent up to six months of every year camping out at a number of field sites in the mountains. I knew as I got my Ph.D. that my time

in the field would go down. When I became a faculty member and started teaching, suddenly I was down to maybe one or two weeks of field work a year, and some years nothing at all. Now that I am older it's a bit easier for me to get back to doing field work. In the US system, you have to work very hard to get a permanent position. But after I was a Professor, I started moving countries, and that is also a lot of work. Now that I am settled, as a mature scientist in France and knowing that SETE it is the last place I will ever work, I am starting again to have time for fieldwork, so it's life coming around full circle.

Climate change: About the "dangerous" limits of global warming

SC: In 2015 at the COP21 in Paris, the agreed-upon maximum limit not to exceed in terms of global warming was 1.5° C. Your research suggests a two-degree cut-off level^[6]. This is 2023, and you indicated that we could reach 3.5°C^[7]. Moreover, in another article published in CNRS News, global warming in France may be worse than thought and may even reach 3.8°C^[8]. What about this limit?

CP: This was the most disturbing part of our conclusions of the Sixth Assessment Report of IPCC (just published in 2021 and 2022). We really are rapidly warming. We have some chance of staying below 2°C, which is the internationally agreed upon cut-off, but it is only with very aggressive actions. My personal feeling is that it's probably going to go beyond 2.5°C even with agressive actions.

It's very upsetting that we are very likely to go over those agreed-upon targets.  You start thinking about what we're going to lose. I've already written that the polar bear probably will not make it.

Now, I am thinking about tropical coral reefs - we know they're very sensitive. When I return to reefs a few years later, I don’t know a single one that is still healthy compared to when I first visited them, whether it's in Hawaii, Australia or  the Caribbean. They are all dying. It starts me thinking “That all whole ecosystem is going to disappear”.  Coral reef biologists have concluded that 1.5°C is the limit for tropical reefs. I don’t see any way we're going to stabilize at 1.5°C, not at this point, not with what is happening globally! On the impacts side, we are seeing some processes starting that we did not think would be seeing yet.  We are already observing some changes in undisturbed systems -  in the Amazon, in the Tundra, all over the world - turning what used to be carbon 'sinks' (sucking up carbon from the air) into carbon sources -  we expected this at some point as Earth continues warming, but not yet.

Thawing permafrost and its consequences

SC: Permafrost thawing is a direct threat to the global climate. Unfrozen ground produces greenhouse gases, and the resulting global warming then further accelerates the thawing of permafrost^[9]. This produces a kind of feedback loop, regardless of the reduction in human emissions ^[10]. The situation sounds very alarming. What do you think?

CP: This is what scares me most among the thousands of conclusions we have from our report. We are already seeing some changes in undisturbed, supposedly healthy natural systems in the tropical Amazon rainforests - not just the Arctic tundra, but in other systems as well. The increase in wildfires of course releases CO₂. Whole systems are converting from being forest to being grassland. None of us had expected to see these long-term trends yet - in places where historical carbon sinks used to take up more carbon than they put out. Honestly, I was anticipating this eventually would happen, but expected it would be twenty, thirty years before we would be seeing this shift in other systems, besides the Arctic tundra. That really shocked me. It is something that just came out rather late in our report as all these numbers were being put together from all these different systems all over the world!  Arctic tundra: yes, that was what we expected because that was already starting to happen even ten, fifteen years ago. That system was already shifting at some monitored sites from being sinks to being carbon sources. But the other systems? They were a surprise. We do have some years to make it better, but, with continued warming, at some point the process becomes irreversible, when it goes over a tipping point.

Technological solutions?

SC: At your Verrall Lecture 2022^[11]  you pointed out that technologies to capture and store greenhouse gases are still being studied in laboratories and will not be operational before decades. In your opinion, since the entire planet is concerned, can an international program accelerate it?

CP: Of course! The more international coordination you have, the faster technology can improve. All of these things are very expensive to fund. I'm thinking partly of specific research funding; but also simply the funding to get different scientists from different disciplines together so that people with slightly different ideas and expertise can all think about the same problem together.  This was one success of the MOPGA program - getting scientists from different fields to understand what each other is doing.

What disturbs me about relying on technology too much is that we are not using technology we already have.  For example, the technology of carbon capture and storage is well developed: this is capturing CO₂, liquefying it, and then burying it where it cannot escape. Carbon-capture and release underground has been used in the oil industry for decades as a way of extracting additional oil. The technology is well developed. In Texas where I used to work, the Bureau of Economic Geology worked to transfer that technology to dealing with global warming. There is one area of Texas coast that is surrounded by an enormous number of coal-fired power plants- Texas exports energy to other states. The Bureau of Economic Geology and the University of Texas developed approaches to capture CO₂ from emissions of these power plants, liquify it and then pump it underground. Texas has enormous salt domes just off the coast - miles of deep, very stable geology –no earthquakes, no volcanos, nothing happening geologically- the perfect situation. This could have been put into large-scale CO₂ storage projects fifteen years ago, but it was not because it wasn't considered economically viable. Capturing, liquefying, transporting and storing CO₂ uses about one third of the electricity that the plant generates, which means you have to charge thirty percent more for electricity. The companies simply said: “Well, we are not going to do this. My electricity would be thirty percent more: consumers are going to buy it somewhere else!”

That is what makes me very pessimistic about technology. This type of carbon-capture and storage has already been developed, we could be doing that now and we are not! Any new technology is going to be expensive! If everyone keeps using a marketplace mentality, we are not going anywhere.

Policy-makers: Awareness of climate change issues

SC: You said, “Policy-makers were asking about tipping points”: “When do we start crossing the tipping point and having collapse of the economic structure destruction of coastal cities, medical systems being unable to deal with increases in diseases, especially tropical diseases, heat-related deaths…?”^[12][5] Are we very close to the climate tipping point? Is it a taboo question?

CP: One of the difficulties dealing with policy-makers is they want these exact answers and, of course, sometimes science cannot give you an exact answer. In terms of tipping points for climate change, we know the processes, we understand the mechanisms, but asking us exactly when that process becomes irreversible is very difficult to answer … We cannot define a specific degree of warming that would shift any particular system over the tipping point. What we can say is that, “Where the two-degree cut-off level for dangerous climate change came from is from all these different fields of science”.

There was agreement that up to two degrees is probably a safe zone for most species, most systems, not all! I think that polar bears are gone under that. Over two degrees is where you start having different systems reaching those tipping-points. We do not know if it is 2.1°C or 2.5°C, 3.0°C. What we know for sure is, “For every degree above the defined dangerous levels of climate change, crossing the tipping point becomes more and more likely”. That is a very hard thing to get across the policy-makers: the science of tipping points is not exact. That does not mean, “We don't understanding what is happening”, but “We have not seen the world doing this before, so we are trying to extrapolate into unknown territory from our own current understanding.” 

SC: In 2018, at Stockholm you insisted: “Policy-makers must consider human driven climate change in any single policy decision [they] make. It is the over-urging problem which affects all other aspects of society and economic systems”^[13]. Do you think they are fully aware today?

CP: No! They still act as though climate change is a separate thing from other problems. I think that you have to get people out of their own “little day to day bubble” to realize what climate change is going to mean. In every case, it is hitting the poorest people and poorest nations hardest. Ironically, cultures that are closest to the land are being hit the hardest because they are closest to the land! Policy-makers are often not there yet: they don't understand the inter-connectedness of global problems.

COP15: Protecting biodiversity

SC: The recent COP15 in Montreal, Canada, reached a landmark agreement on biodiversity. In particular, “By 2030: Protect 30% of Earth’s lands, oceans, coastal areas, inland waters”^[14]. With this agreement, are you now confident about preserving biodiversity in the coming years?

CP: I am extremely thrilled by this agreement! I did not expect it at this point. One of the problems for implementing it is that the biodiversity COP meetings are one group of people. Climate change COP meetings are a different group of people; it is the same in different countries.  The two groups have different targets and they need to talk to each other. I'm hoping that message gets into the actual agreements about carbon reductions. In other words, I hope that those two international policy-making groups come together to come up with a joint-plan for protecting biodiversity, and thereby protecting healthy ecosystems that will continue to be carbon sinks, which then helps each nation achieve the climate goals.  All is interconnected. That is something we worked very hard on in our last report, including with the joint-report with IPBS, to really pull together connections between healthy systems, healthy biodiversity, reducing carbon emissions and stabilizing climate.

Just imagine…

SC: Imagine a world government and you are President of it.  What are your three immediate actions in favour of climate change and biodiversity?

CP: Well, the first two are easy! To implement the thirty percent protection that has been agreed on. Then implement a series of restoration efforts because it is not clear thirty percent is sufficient.  For example, restoration of peatland ecosystems that are high carbon sinks is extremely important. But also doing restoration in a way that recognizes that systems also need to be used by humans; developing much better joint planning of biodiversity conservation along with restoration of systems that can provide food for humans. It is possible! The third thing that I would implement is a much stronger science-based education system. I would really like to have some fundamental changes in the education system to teach children science right from the beginning. Even at five years old, you can teach them the water or carbon cycle, and how humans are changing these cycles. I think people don't give children enough credit - they can really absorb the harder sciences.

Now that you are a researcher in France

SC: Following President Macron’s program MOPGA^[15], you are continuing your research in France. What notable differences in scientific research do you find in France compared to the United States or UK for example?

CP: The biggest difference is there is no equivalent to CNRS in either the UK or the USA: an institute devoted to pure research, where you are not obligated to spend half your time teaching. Being in a position of one hundred percent research allowed me to be Coordinating Lead Author for the IPCC. I could not have done that job if I were still in teaching a full load that would be normal for faculty in Britain or in the USA.

The other difference, which I think it is not just France but Europe as a whole, is that there is more encouragement for scientists to work with policy-makers. The USA still has a very traditional approach; if you are at the university, you are really discouraged from working with policy-makers or in more applied fields. In Europe as a whole, I feel like those lines are not so black and white. Researchers can do what I call basic research, and also a bit of applied work, as well as working with the policy-sector.

SC: You are now the Director of the SETE station in Moulis. Do you have a specific research programme that you want to set up? In short, what programme and actions?

CP: Gladys Barragan-Jason was my post-doc. She is a psychologist by training and I said, “Look, we need psychologists working on biodiversity impacts, in climate change. How do you change people’s minds? How do you get people to recognize that climate change effects them?” We developed a project with the local schools. She was able to apply for an interdisciplinary position because, through our project, she had to work with ecologists (me) and learn ecology as well. I still want to support basic ecological and evolutionary research, but I very much support other approaches that include looking at human actions: how to influence human behavior?, and how can we begin to change how the general public perceives science and nature? I would like to think I have already encouraged this more interdisciplinary approach.

SC: SETE station is one of five member laboratories of the Federation “Agrobiosciences, Interactions and Biodiversity”. What synergies do you see or would you like to implement with other Federation laboratories?

CP: I have not thought about specific laboratories, but I am certainly hoping to help expand our network. I have been in contact with some of the national park people in the Pyrenees. I would like to see more interregional actions of that kind; including having agricultural scientists explore alternative, more ecologically-sound approaches than modern industrial agriculture.

SC: Yes, but within the Federation, there are five laboratories. What would you like to do in terms of research approach with the other laboratories of this Federation, maybe for example the lab EDB in Toulouse?

CP: We collaborate in the sense that we go to each others' seminars and work on collaborative projects via grants. I guess I would be interested in more research that looked at the impact of traditional agriculture on biodiversity, on maintaining cultural values, on providing ways of earning money, at the same time as preserving biodiversity and having a lower carbon footprint. It would be good to have some hard-core science done that would help help us understand what is working in this area in Ariège.  Why is it able to maintain high biodiversity alongside farming?   And how this approach might be translated into other regions of France?

There is a lot of industrial farming in France. If we could think of a way of modifying that to still produce good yields of food but in a more climate and biodiversity friendly way, that would be really good. I think France is one place where it could be done. There is a willingness and interest in maintaining traditional farming methods. I think if we were going to shift industrial agriculture anywhere in the world, France could be a real icon for how to do it.  But for this to be really successful it would help to have more interactions between INRAE and CNRS. I do know people at INRAE; it is just a matter of getting those personal interactions going and developing some joint projects.

We need a coming together of minds and expertise to achieve the kind of climate resilient development that we talked about in the IPCC: You must have agricultural scientists and natural scientists coming together! It is a big task!

Epilogue

SC: Today, in your entire scientific life, what are you the proudest of?

CP: I am very proud to what we achieved in the last IPCC report that I was very heavily involved in. My level of participation was much more intense because I was head of a chapter and author of the summary for policy-makers. I got very involved in the public outreach side, helping to develop a set of Frequently Asked Questions which will be published as a booklet for the public. This was really a full time and a half job!

I am also incredibly proud of my butterfly work particularly with Edith’s Checkerspot that lives in the western half of the USA. We've really been able to show evolution in action, in real time, in response to invasive species and to climate change. That is very exciting as a scientist and of course being able to get it published in Nature is very nice too!

SC: You bought a farm in the Pyrenees in Ariège. Could it become a kind of refuge for you in the years to come?

CP: Yes! We have already had this happen! In the pandemic, we loved it. We loved the lockdown; all the traveling stopped. We have a beautiful home overlooking the mountains and a valley. We set up our offices in a room with huge glass windows. It is already been a little refuge! We hope to live out our old age in our little bubble and stay in the Ariège. I'm quite serious.