The award Nobel Prize in Physics 2021 It has been awarded “for pioneering contributions to our understanding of complex systems” by three researchers. Half of the award is shared jointly Syukuro manabe and Klaus Hasselmann “for the physical modeling of the Earth’s climate, the quantification of the variability and the reliable prediction of global warming”, analyzing the human influence in this process.
The other half is awarded to Giorgio Parisi “for the discovery of the interaction of disorder and fluctuations in physical systems from the atomic to the planetary scale.” His groundbreaking contributions to the theory of disordered materials and random processes are honored.
The Japanese Syukuro Manabe and the German Klaus Hasselmann have laid the foundations for our knowledge of the Earth’s climate and how humanity influences it.
The complex systems they are characterized by that randomness and disorder, reason why they are difficult to understand. This year’s award recognizes new methods for describing and predicting their long-term behavior.
A complex system of vital importance to humanity is the Earth’s climate. Syukuro manabe (Shingu-Japan, 1931) showed how increasing levels of carbon dioxide (CO2) in the atmosphere causes an increase in 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 to explore the interplay 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 Klaus Hasselmann (Hamburg-Germany, 1931) created a model that relates 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, fingerprints, that both natural phenomena and human activities imprint on the climate. His methods have served to demonstrate that the increase in the temperature of the atmosphere is due to human emissions of CO2.
Italian Giorgio Parisi discovered hidden patterns in messy complex materials
For its part, Giorgio Parisi (Rome-Italy, 1948) discovered around 1980 hidden patterns in messy complex materials. His discoveries are one of the most important contributions to the theory of complex systems.
These make it possible to understand and describe many different and seemingly totally random materials and phenomena, not only in physics but also in other very different fields, such as mathematics, biology, neuroscience and machine learning.
Regarding the current climate crisis, Parisi has declared after learning that he is one of the winners: “It is clear that for the future generation, we have to act now very quickly.”
The chairman of the Nobel Committee for Physics, Thors Hans Hansson, stressed: “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. All laureates of this year have contributed to a better understanding of the properties and evolution of complex physical systems. ”