ClimateAdaptation.life: The five leading coffee-producing countries, Brazil, Vietnam, Colombia, Ethiopia, and Indonesia, have experienced, on average, 57 additional days per year of heat harmful to coffee crops as a result of climate change. Temperatures above the 30°C (86°F) threshold are considered harmful to coffee in the major producing countries. How do you think these countries can collaborate? Is there any room for them to collaborate to pull together their knowledge on climate change adaptation?

Kristina Dahl: Yeah, that's an interesting question. So I think when it comes to addressing climate change, the mitigation aspect is very clear: individual governments or entities know what needs to be done. They have to cut emissions, and we know how to do that. But when it comes to adapting to climate change, solutions are often much more specific to a place or to a particular aspect of society that needs to adapt. And so it tends to be much more difficult to share knowledge on climate adaptation across different sectors and different settings. That said, we are seeing different ways that coffee farmers are trying to adapt to a warming world. And some of those strategies could apply across different countries. So, practices like sustainable agriculture can help farmers balance crop productivity with climate resilience. For instance, they are planting taller tree canopies among coffee plants to protect them from harmful heat. They can also mix crops to improve the soil, with ecological benefits. I think there's also potential to consider how the Paris Agreement can support adaptation for coffee-growing communities around the world.

We know that one of the goals of the Paris Agreement is for wealthier countries to provide financial assistance to developing countries to help them adapt to climate change. And that mechanism is far from perfect within the Paris Agreement. But it could work for particular commodities that the world depends on.

At COP 30, a growing number of countries expressed interest in joining climate adaptation measures and mechanisms, and in financing them. Do you think there are specific institutions and funds targeting coffee producers effectively?

I don't think there are specific funds that would target that. The two main mechanisms through the Paris Agreement are the Adaptation Fund and the Loss and Damage Fund. Both of those are severely underfunded, and the process for accessing funds through each is very onerous. for developing countries. So, that's why I say it's not a perfect mechanism by any means, and it's certainly not specific to agriculture or coffee. But it is something to be thinking about as we increasingly recognize that climate change is affecting coffee production.

As I understand it, you mentioned the possibility of switching from intensive to less intensive cultivation, with potential benefits for nature in terms of biodiversity. Do you see this practically being implemented with good results, and if so, in which geographies?

That's another good question. There have been some studies of coffee cultivation in Mexico and Costa Rica, countries that have been involved in programs using shade trees to improve soil, reduce exposure to extreme heat, and enhance ecological habitat around coffee-growing. In this sense, there are some positive results, but it is also tricky because coffee grown in full sun tends to yield more. So there can be trade-offs between, sort of, soil and ecological health and resilience, and the highest yield.

Are there any other specific technological advancements or traditional cultivation methods that could help deal with the increase in temperatures? What are the other measures?

I would say that some experimentation is happening to try growing coffee in new places. As the climate warms, some areas may become less suitable for coffee growing. Particularly if you think of coffee grown in the tropics, it is grown within a particular altitude band. You could think of moving the crop up the mountain. But at some point you run out of mountain.

So are there other regions of the world that might become more favorable for coffee production in the near future? Are there experiments in this sense?

In the United States, some experimental coffee growing is happening in California and along the Gulf Coast, the northern coast of the Gulf of Mexico. And so, while those areas aren't suitable for production at scale, it's worth considering: there might be regions that were unsuitable in the past that could become suitable in a warming world.

This is a very interesting point. Something very similar happens with wine production. Do you think that there are specific requirements in terms of, for instance, soil, water, and amount of rainfall? For instance, would it be reasonable to test crops in Egypt, where the rainfall is very limited?

Coffee plants do have an optimal range for temperature and rainfall. In the study we just finished, we looked at temperature and how it's affected by climate change. We know that coffee plants like to receive annual rainfall between 60 and 80 inches (152 to 203 cm). The plants are not particularly resilient to drought. So a place like Egypt or even parts of California could be problematic. So, in terms of identifying future regions, it will be a matter of looking to climate model projections and seeing which locations might fit those temperature and rainfall patterns. Seasonality of rainfall is also important: when it falls, how much falls at once, because we know that extreme rain at the wrong time of year and too much can cause decreased coffee yields. And, as you mentioned, there's also the soil to consider. Soil and climate conditions really affect the coffee's flavor profile, which is why coffee from Ethiopia tastes different from coffee grown in Brazil. It's also about what the coffee will taste like as it grows in those soils.

Another possible climate adaptation measure: changing coffee variety. For instance, I think there has been a shift from Arabica to Robusta, if I'm not wrong. Could this also be a climate adaptation measure in your view?

Yes, so the two main varieties of coffee plants are Arabica and Robusta. And Arabica tends to be more temperature-sensitive to extreme heat than Robusta; even above 25 degrees C, it is suboptimal. Robusta is more robust, reaching about 30 degrees C. It's difficult to say whether a shift to Robusta would satisfy the desires and needs of the global coffee-drinking community, because they do taste different. Here in the United States, most of the coffee you see in coffee shops, cafes, or grocery stores to brew at home is Arabica.

Do you think that the change in preferences could also be an adaptation measure itself? In other words, could the societies be called to change the way they drink their coffee? If, for instance, prices skyrocket, there could be changes in demand.

But there could also be issues in the production, no?

Yeah, that's right. I mean, most coffee worldwide is produced by small farmers. So, price shocks can really affect not just consumers but producers as well. I think it's interesting to think long-term about how preferences for different foods, different drinks, change over time in our society, and obviously not in a monolithic way, things might change one way in the United States, another way in Italy, another way in Egypt. But we do see changes in preferences over time. I'm thinking about the United States and the growth of the wine industry, and the rise of things like wine bars, which we didn't have 40 years ago. So preferences do change sometimes in response to deliberate marketing, but also in response to changes in the supply of different crops and commodities. Very interesting.

Considering the growing risks for farmers, this could also increase somewhat the concentration of production, dismantling the business model we have seen for many years, which, as you mentioned, is based on small producers, small farmers, small allotments producing very high-quality coffee. Especially for high-quality coffee, which is sold at higher prices but often also meets higher ethical standards. In other words, do you think that this correlation between fair trade and specialty coffee could be impacted negatively by climate change?

Yeah, that's a really interesting question. I honestly don't know a lot about the fair trade aspects of coffee from an expert perspective. Multiple stresses indeed add to the challenge of sustainability .

Do you think that associations of coffee producers could support farmers in adapting to climate change? And if so, what could we do?

Oh, that's another good question. But we are not the right people to comment on that: we're a non-policy, non advocacy group.

And what can we do as journalists, as experts, as people interested in sustainability?

I think the more often we can connect coffee prices to climate change, the more people see the reasons behind price fluctuations, and the more they can help show the vulnerability of these crops to different forces, whether climate-driven or economically driven through things like tariffs.