Jessica Seddon and Paul Edwin Curtis on responding to future climate risks

Responding to Future Climate Risks: What, Where, and When to Expect?

What could the world look like at 2^oC, 3^oC, or even higher levels of global warming? What are the risks to societies and ecosystems? What can the world tolerate?

As we pass 1.25^oC, many of these risks are already being introduced through more frequent heat extremes. For instance, during the 2003 European heatwave, an estimated 45,000 people lost their lives to heat-related stress. More recently, as many as 6,500 people were estimated to have lost their lives building the FIFA World Cup stadium in Qatar where temperatures extremes can approach 50^oC.

“Heat is something which is now very predictable” — Jessica Faieta, who has held numerous leadership positions throughout her 30-year career with the United Nations, most notably in Latin America, emphasizes that heat extremes are a relatively new problem confronting decision-makers, but one which is rapidly dominating discussions. Whilst climate discussions are so often focused on the future, these changes are posing very real threats to human survival now. Matthew Huber, a Professor in the Department of Earth, Atmospheric, and Planetary Sciences at Purdue University, was among the first scholars to identify that human adaptability to increasing heat stress may become impossible in many regions.

Here, the science is clear — endotherms (warm-blooded animals) can only regulate bodily temperature to within safe limits if environmental conditions, determined by temperature and humidity conditions do not exceed a certain threshold. Professor Huber and his colleagues demonstrated that as little as 2^oC global warming can push environmental conditions in many parts of the world beyond this ‘adaptability limit’. As we look to the future, there is growing consensus that 2^oC global mean warming is essentially locked in, and there is good understanding that each degree of additional warming will only exacerbate the stress on societies.

Under these scenarios, many parts of South and Southeast Asia, and West Africa, which are already experiencing temperatures more than these limits for several days of the year, could come to see several weeks of the year when heat exceeds habitability limits. It’s not just people and ecosystems - heat impacts critical infrastructure, including roads and railways. Ultimately, Professor Huber, and other analysts are aware that increasingly adverse conditions have the potential to shift food production and agriculture away from many of these areas, posing potentially seismic shifts in economic development and trade patterns as the world continues to warm.

The very real concern is that as days of extremes turn into weeks, and even into months, there is potential for inequality to grow. How can science and policy work better together?

For Ms Faieta, it is imperative that nations recognize the de-facto reality that they must take matters into their own hands now, whilst also recognizing that not everything can be done at once — “long-term planning is not expensive, but poor planning is.” This underscores the necessity of robust regional projections of local thermodynamic conditions, and a well-articulated discussion of uncertainties from climate modeling. She emphasized that this knowledge could inform the construction of early-warning systems, much in the same way we have for other natural disasters.

Climate financing is notoriously difficult to navigate, and the reality for many nations is that large international support may arrive too late, or not at all. Both speakers emphasized that geopolitics so often complicates what would otherwise be conceived as a rational actor problem. Whilst making the case for larger investments continues to play out, small, incremental changes in many parts of the world and the inclusion of climate risks in national budgets over the coming decades could have significant positive outcomes.

She continuously pointed to the option of enshrining heat and other climate risks into national laws, stating “we know this is a problem, here’s how we should deal with it practically.” From her experiences with the UN, she has seen how inexpensive tactics such as retrofitting apartments, schools; even increasing the number of trees on streets, can have tangible, positive outcomes for many communities. Professor Huber added - “give people the resources and they will find a way.”

Climate financing is notoriously difficult to navigate, and the reality for many nations is that large international support may arrive too late, or not at all."

Secondly, it’s clear to both scientists and decision-makers that the problem of heat is inseparable from water-related risk, changes in regional hydroclimate, and other factors which add to create compounding risks. In Ms Faieta’s native Ecuador - a country proud of its large renewable energy infrastructure, dominated by hydroelectric power generation - increasing droughts are threatening the reservoirs upon which hydroelectric power depends. In recent years, this has led to national blackouts.

With Ecuador on her mind, Ms Faieta pointed to the key role for diversification of energy sources. Another nation, Uruguay, which has transitioned to 98% renewable energy, has diversified energy sources evenly between hydro, solar, and wind with resilience to climate change at the forefront of decision-making. This was largely achievable through partnerships with the United Nations Environment Program, underscoring the potential for multilateral agencies to accelerate adaptation.

Positive examples such as these could pave the way for other nations to follow suit and allow the kinds of continuous learning which Ms Faieta emphasized as crucial when moving forward.

Who could take the lead in the future?

Paul Edwin Curtis is a 5^th year Ph.D. candidate in climate dynamics and a NASA Future Investigators fellow in the Department of Earth and Planetary Sciences at Yale, and is the inaugural World Climate Research Program My Climate Risk student fellow at Yale’s Jackson School of Global Affairs.

Jessica Seddon is a senior lecturer in the Jackson School of Global Affairs, Director of the Deitz Family Initiative on Environment and Global Affairs, and convenor of the Yale My Climate Risk Hub.

This article first appeared in the Environment@Jackson Substack