CM – Climate modelers and theorists of complex systems share Nobel physics


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Nobel laureates in physics 2021, Klaus Hasselmann, Giorgio Parisi and Syukuro Manabe. Photo credit: J. J. Guillen / EPA / Shutterstock; Tania / Contrasto / Eyevine; Markus Marcetic, Royal Swedish Academy of Sciences

Three researchers won the Nobel Prize in Physics in 2021 for their work describing complex physical systems – including basic research that created a groundbreaking mathematical model of the Earth’s climate and predicted that carbon dioxide levels would rise would increase the global temperature in the earth’s atmosphere.

Syukuro Manabe and Klaus Hasselmann share half of the 10 million Swedish crowns (1.15 million US dollars) prize for this model. Theoretical physicist Giorgio Parisi of the Sapienza University in Rome shares the other half of the award for his contributions to the theory of complex systems. His work has influenced many areas from neuroscience to the packaging of granular materials, the Nobel Committee said in its October 5th announcement.

« These are two different awards, but there is one common theme that goes with this order has to do with these fluctuations together, which can lead to something we can understand and predict, ”said Thors Hans Hansson, chairman of the Nobel Committee in Physics. « We can predict what will happen to the climate in the future if we know how to code the chaotic weather. »

Manabe, now at Princeton University in New Jersey, showed how an elevated one in the 1960s Carbon dioxide levels in the earth’s atmosphere lead to increased surface temperatures, and developed early mathematical models of the planet’s climate. About a decade later, Hasselmann from the Max Planck Institute for Meteorology in Hamburg built on this work to create a model that links weather and climate.

“Manabe showed us how and why an increase in CO2 leads to global warming. Hasselmann has shown that it happens, ”says climate scientist Bjorn Stevens, also at the Max Planck Institute for Meteorology. He adds that the institute is “thrilled” that the two have received the “first Nobel Prize for the science that underpins our understanding of climate change”.

Jürgen Kurths from the Potsdam Institute for Climate Impact Research says that a “ ingenious contribution ”by Hasselman in the 1970s was the introduction of the first“ conceptual model ”for the earth’s climate – a simple system of equations that captures global phenomena with just a few variables. This approach has provided complementary insights to those from global circulation models, which are geographically detailed brute force calculations. « You usually need a computer to simulate [conceptual models], but it’s a lot faster and easier, » says Kurths.

Despite his advanced age of 89, Hasselman continues to actively pursue the field and encourages researchers to try non-traditional approaches, adds Kurths.

Gabriele Hegerl, a climate modeler at the University of Edinburgh, UK, who is a postdoctoral fellow worked with Hasselman says he was a « fantastic » mentor and coach who was « full of ideas and enthusiasm ».

« I am very happy that Suki and Klaus were selected together as they have both made tremendous contributions in different ways and are two giants of climate science, » she adds. “I still use Suki’s old numbers from early work on absorption and the physics of the atmosphere in my classes, and his work is fundamental to understanding climate and therefore climate change.”

Manabe was “surprised” when he heard he won the award, said John Wettlaufer, an earth and planetary scientist at Yale University in New Haven, Connecticut who was a member of the Nobel Committee on Physics. « He said, ‘But I’m only a climatologist.' »

Parisi started his career in particle physics, but his research has since touched many other branches. In the late 1970s he turned to the theory of complex systems, where he discovered a hidden and counterintuitive kind of order in the interactions of many objects. In simpler systems – such as magnetic materials – atoms tend to orient themselves parallel to their neighbors, but complex systems are less predictable. Nevertheless, Parisi has found that they satisfy a symmetry that only becomes noticeable when comparing the arrangement of the individual atoms on different scales, says the physicist Federico Ricci-Tersenghi from Sapienza.

« It has opened a way to complex phenomena to see and interpret that had been missing up until then, ”says Ricci-Tersenghi, a former student of Parisi and a long-time employee. The theory has even worked for systems that at first glance seem completely random, such as the structure of glass, he adds.

Parisi’s research examines the underlying disturbance and fluctuations and predicts emerging behavior, said Runners. The link between his, Manabe’s, and Hasselmann’s work is that variability is the key to predictability, he said. « We understand that emerging phenomena sometimes require you to look at all of the intricate physical mechanisms and put them together to make a prediction. » Kurths says he was pleased to see Parisi – and with Ricci-Tersenghi says that his research group has also maintained a “happy environment”, and that his mentees are always encouraged to share their curiosity and their intellectuals Interests to follow.

In response to news of his Nobel Prize, Parisi told reporters during the announcement, « I was very happy and didn’t really expect it. » I put the phone near me. ”

The award comes ahead of a crucial climate conference – the 26th United Nations Climate Change Conference, to be held in Glasgow, UK in November n, should take place. « It is very urgent that we make a very strong decision and proceed at a very fast pace, » said Parisi of the climate negotiations. « For future generations, we must act very quickly now. » When asked if the Nobel Committee was sending a message to world leaders with the award, said Göran Hansson, Secretary General of the award-winning Royal Swedish Academy Sciences: Theory and Solid State Physics. ”He added,“ Global warming is based on solid science. That is the message. ”


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Physics,Nobel Prize in Physics,Syukuro Manabe,Klaus Hasselmann,Giorgio Parisi,Climate change,Royal Swedish Academy of Sciences,Physics, Nobel Prize in Physics, Syukuro Manabe, Klaus Hasselmann, Giorgio Parisi, Climate change, Royal Swedish Academy of Sciences,,Nobel prizes,Nobel prize in literature,Awards and prizes,Books,Culture,Physics,Science,,,,

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