Physics Nobel rewards trio for contributions to climate models

Secretary General of the Royal Swedish Academy of Sciences Göran Hansson (center) announces the winners of the 2021 Nobel Prize in Physics at the Royal Swedish Academy of Sciences in Stockholm, Sweden,

October 5, 2021

Three scientists won the Nobel Prize for physics on Tuesday for work that found order in seeming disorder, helping to explain and predict complex forces of nature, including expanding our understanding of climate change.

Syukuro Manabe, originally from Japan, and Klaus Hasselmann of Germany were cited for their work in “the physical modeling of Earth’s climate, quantifying variability and reliably predicting global warming. The second half of the prize was awarded to Giorgio Parisi of Italy for “the discovery of the interplay of disorder and fluctuations in physical systems from atomic to planetary scales.”

In the face of the challenges of climate change, Mr. Hasselmann told The Associated Press he “would rather have no global warming and no Nobel prize.’’

Across the Atlantic at the same time, Mr. Manabe noted in an interview that figuring out the physics behind climate change was easier than getting the world to do something about it.

All three scientists work on what are known as “complex systems,” of which climate is just one example. But the prize goes to two distinct fields of study that are opposite in many ways but share the goal of making sense of what seems random and chaotic in such a way that it can be predicted.

Mr. Parisi’s work centers around subatomic particles and is somewhat esoteric and academic, while the work by Mr. Manabe and Mr. Hasselmann is about large-scale global forces that shape our daily lives.

The judges said Mr. Manabe, 90, and Mr. Hasselmann, 89, “laid the foundation of our knowledge of the Earth’s climate and how human actions influence it.”

Starting in the 1960s, Mr. Manabe, now based at Princeton University in New Jersey, created the first climate models that forecast what would happen to the globe as carbon dioxide built up in the atmosphere. Scientists for decades had shown that carbon dioxide traps heat, but Mr. Manabe’s work put specifics and prediction into that general knowledge. It allowed scientists to eventually show how climate change will worsen and how fast depending on how much carbon pollution is spewed.

About a decade later, Mr. Hasselmann, of the Max Planck Institute for Meteorology in Hamburg, Germany, helped explain why climate models can be reliable despite the seemingly chaotic nature of the weather. He also developed ways to look for specific signs of human influence on the climate.

Mr. Hasselmann said the problem with climate change is that it exists on such a large time scale that people have difficulty comprehending it.

“People tend to deny the problem until it’s too late,” Mr. Hasselman said.

Meanwhile, Mr. Parisi of Sapienza University of Rome, “built a deep physical and mathematical model” that made it possible to understand complex systems in fields as different as mathematics, biology, neuroscience, and machine learning.

His work originally focused on so-called spin glass, a type of metal alloy in which the atoms are arranged in a way that changes the material’s magnetic properties in apparently random ways that baffled scientists. Mr. Parisi, 73, was able to discover hidden patterns that explained this behavior, theories that could be applied to other fields of research, too.