The 2021 Nobel Prize in Physics has been awarded to two climate change experts in addition to an Italian scientist, it was announced Tuesday.
The Japanese-American Syukuro Manabe and the German Klaus Hasselmann have been recognized for their physical modelling of climate change.
Half the prize will go to Manabe, 90, and Hasselmann, 89, for physically modelling the Earth's climate and for having reliably quantified and predicted climate change variability, the jury said.
The jury’s announcement came on Tuesday, a month before the COP26 climate summit in Glasgow, where global warming will top the agenda.
The other half went to Italian theorist Giorgio Parisi, 73, for discovering the interplay of disorder and fluctuations in physical systems, from the atomic to the planetary scale.
The jury thus highlights the new methods to describe complex systems and to predict behaviour in the long term. One of them, of vital importance to humanity, is the Earth's climate. In its argument, the Royal Swedish Academy of Sciences points out that complex systems are characterized by randomness and disorder and are difficult to understand.
The discoveries recognized this year demonstrate that our knowledge of climate is supported by a solid scientific basis, based on a rigorous analysis of observations, said Thors Hans Hansson, chairman of the Nobel Committee. All of this year's winners have contributed - he added - to better understanding the properties and evolution of complex physical systems.
Manabe demonstrated how increased levels of carbon dioxide in the atmosphere lead to increased temperatures on the Earth's surface.
In the 1960s he led the development of physical models of the Earth's climate and was the first person to explore the interaction between radiation balance and vertical transport of air masses. His work laid the foundation for the development of current climate models. About ten years later, Hasselmann created a model which links weather and climate, thus answering the question of why climate models can be reliable despite changing and chaotic weather.
He also developed methods to identify specific signals, such as fingerprints, that both natural phenomena and human activities imprint on the weather. His methods have been used to show that the increase in temperature in the atmosphere is due to human emissions of carbon dioxide.
Around 1980, Parisi discovered hidden patterns in messy complex materials. His findings are among the most important contributions to the theory of complex systems. They make it possible to understand and describe many materials and phenomena that appear to be random, not only in physics but also in other very different areas, such as mathematics, biology, neuroscience, and machine learning.
Manabe is affiliated with Princeton University in the US, while Hasselmann is a professor at the Max Planck Institute for Meteorology in Hamburg. Parisi is a professor at the Sapienza University of Rome.
The announcement of the Physics award follows that of Medicine, which went to molecular biologists David Julius and Ardem Patapoutian for their discoveries about temperature and touch receptors.
Still to be announced this week are the winners in Chemistry, Literature, Peace and Economy. The Nobel Foundation has already announced that the glittering prize ceremony and banquet normally held in Stockholm in December for the science and literature laureates will not happen this year due to the coronavirus pandemic. Like last year, laureates will receive their awards in their home countries.
A decision is yet to be made about the lavish Peace Prize ceremony held in Oslo on the same day.