Nobel Prize in Physics for the science of complex systems that help forecast the climate

Nobel Prize in Physics for the science of complex systems that help forecast the climate

The Nobel Prize in Physics today recognized three researchers for their “pioneering” contributions to understanding so-called complex physical systems, one of which is the Earth’s climate, which allows reliable prediction of global warming.

The award is divided this year into two halves, one for the Japanese-American Syukuro Manabe and the German Klaus Hasselmann and the other for the Italian Giorgio Parisi.

Manabe and Hasselmann laid the foundation for knowledge of Earth’s climate and how Humanity has influenced it. The Nobel recognizes them for their “physical modeling of the Earth’s climate, the quantification of the variability and the reliable prediction of global warming“.

Parisi, for his part, revolutionized the theory of disordered materials and random processes from the atomic to the planetary scale, said the Royal Swedish Academy of Sciences, the institution that grants the award.

The winners’ findings demonstrate that climate knowledge rests on “a solid scientific foundation, based on a rigorous analysis of observations“, Highlighted in a press conference the president of the Nobel Committee for Physics, Thors Hans Hansson.

Part of the knowledge awarded this year has a close relationship with climate change and Parisi was asked about it, who spoke by phone at the press conference in which the award was announced.

The Italian physicist then sent a message to the leaders who will participate in the next United Nations Conference on Climate Change (COP26) in the United Kingdom to whom urged to make strong decisions to curb climate change.

In its explanation of the award, the Academy of Sciences highlighted that complex systems have been studied for centuries and that the Frenchman Joseph Fourier was already busy in the 19th century to investigate the energy balance between the solar radiation to the ground and radiation from the ground.

At the end of the 19th century, the Swedish Svante Arrhenius, awarded the 1903 Nobel Prize in Chemistry, revealed the physics behind this effect, providing an important piece to understand the impact of carbon dioxide (CO2).

Current climate models

In the 1950s, Syukuro Manabe, who emigrated to the United States after World War II, began to study how higher levels of CO2 can cause an increase in temperatures, but instead of focusing on the balance of radiation it did so in the transport of air masses and the latent heat of water vapor.

Thus, he discovered that when the level of CO2 was doubled, global temperature rose more than 2 degrees, and his work laid the foundations for the development of current climate models.

A decade later than his colleague, the German Klaus Hasselmann created a model that links time and climate, thereby answering the question of why climate models can be reliable even though the weather is changeable and chaotic.

Hasselmann further discovered that changes in solar radiation or greenhouse gas levels leave unique signals (footprints) that can be separated, a method that can be applied to the human effect on the climate system.

Manabe, Hasselmann and Parisi succeed the British Roger Penrose, the German Reinhard Genzel and the American Andrea Ghez, distinguished in 2020 for their discoveries related to black holes.

Parisi will receive half of the 10 million Swedish crowns (980,000 euros, $ 1.1 million) with which the Nobel is endowed, while his colleagues will divide the other.

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