Dr. Flavio Lehner is an Assistant Professor of Earth and Atmosphere Science at Cornell University. His research investigates the influence of internal and externally-forced variability on our ability to understand and project climate change on global to regional scales. It aims to improve our understanding of the dynamics that govern this variability and hence the uncertainties involved in climate projections.
He is interested in questions such as: Why are climate projections uncertain? Can we reduce this uncertainty by improving models through dissection and better understanding of the physical processes involved? What are the dynamic and thermodynamic contributions to regional changes in temperature and precipitation and its associated impacts such as heatwaves, droughts and compounded extreme events? How do ongoing and projected changes impact society, ecosystems and natural resources that humans depend on?
His toolbox includes analysis of coupled climate, atmosphere-only, and hydrologic model simulations, climate reconstructions, and observations. His motivation to solve not only disciplinary but also interdisciplinary problems has led to a broad set of applications from paleoclimate reconstructions to hydroclimate impact studies, allowing him to build an extensive network of collaborators at the intersection of fundamental science and applications.
What is the role of the scientist in society and why (in general and in the personal sense)? How can the scientist fulfill that role best?
I think the role of a scientist in society is to be an agent for truth, to provide the best-informed and most neutral answer possible to a particular question. This part is straightforward in my view. The challenge lies in situations where the answer to a scientific question has direct relevance to society.
I’m a climate scientist, so I’ve been aware of this challenge for a while. A thought experiment: in 2012 the Higgs bosom was detected for the first time, relying on a 5-sigma signal in the data of a big measurement campaign. In other words, the probability that the scientists were wrong and were not actually looking at the Higgs bosom was 1 in ~3.5 million. Small enough to declare discovery. Celebrations were in order. No public outcry, no distrust in science, just awe at this result, which – no offense to the scientists – has little consequence for the average human.
The detection signal for human-caused climate change passed the 5-sigma level in about 2005. Much like with the Higgs bosom, this result was predicted decades before, showcasing one of the fundamental achievements of humans – the ability to predict the future based on our understanding of how the world works.
However, the public and private commentators continued to debate whether climate change is even real, let alone human-caused. Only in recent years has society moved beyond the “Is it happening? Is it us?” to the “How do we deal with it?” question. My guess is this is because climate change and efforts to combat it do have consequences for society.
The role of a scientist in this overlap of science and societal interests is bit more difficult to articulate. I believe we have a duty to speak out against people misrepresenting our scientific results, we cannot just deliver the answer and not care how it is used. However, one has to clearly distinguish between talking about the interpretation of scientific results and the political and societal actions that should or should not follow from it.
The former is a question of science, the latter of values. For example, society can acknowledge the scientific result that humans are changing the climate with largely negative consequences for future societies. But it can decide to not value future societies and hence ignore the issue.
A scientist should speak to the first part as a scientist and to the second part as a citizen (through voting, etc). The landscape has shifted a bit in recent years with the Paris Agreement on climate mitigation targets. As governments have signed up to certain emissions reductions, scientists now can speak to what needs to be done, but again not from a value perspective, but from a scientific perspective of how to reach the agreed-upon target.
I am fortunate to profit from excellent role models like Ben Santer, Katharine Hayhoe, or Reto Knutti, and also my PhD advisor Thomas Stocker, who have navigated this space on the climate science side for decades.