The Nobel Prize in Physics has been given to three scientists for their work in understanding complex systems, such as the Earth’s climate, in 2021.

At a ceremony in Stockholm, the winners were revealed as Syukuro Manabe, Klaus Hasselmann, and Giorgio Parisi.

Manabe and Hasselmann’s research resulted in climate computer models that can anticipate the effects of global warming.

The 10 million krona (£842,611) prize pool will be split among the winners.

Predicting the long-term behavior of complex physical systems like the climate is extremely difficult. Understanding global warming as a planetary issue has thus necessitated the development of computer models that predict how it will respond to growing greenhouse gas emissions.

Indeed, the prize comes as world leaders prepare for COP26, the United Nations’ climate summit, which will take place in Glasgow in November. “We have to move immediately in a very quick and not with a major delay,” Prof Parisi remarked when asked about the timeframe.

Climate models based on the winners’ research are an important element of the evidence used by leaders at COP26 to make decisions.

Japan-born Senior meteorologist Syukuro Manabe, 90, of Princeton University in New Jersey, illustrated how rising amounts of carbon dioxide in the atmosphere may lead to higher temperatures at the Earth’s surface. He was a pioneer in developing physical climate models in the 1960s.

Klaus Hasselmann, 89, of Hamburg, Germany’s Max Planck Institute for Meteorology, developed a computer model that connected weather and climate almost a decade later. His research clarified why climate models can be trusted despite the unpredictable and chaotic nature of the weather.

On the surface, Prof Parisi’s original research, which he is presently doing at Rome’s Sapienza University, appears to have little to do with climate change.

It was about a metal alloy known as spin glass, in which iron atoms were mixed at random in a grid of copper atoms. Despite the fact that there are just a few iron atoms in the material, they have a profound and perplexing effect on its magnetic characteristics.

The Nobel Committee, on the other hand, viewed spin glass as a microcosm of the Earth’s complicated climatic behavior. On atomic and planetary sizes, complex systems may share characteristics like chaos and disorder, as well as behavior that appears to be driven by chance.

Parisi, who is 73 years old, discovered that underlying laws affect the seemingly random behavior of solid materials, and devised a mathematical model to represent them.

“What emerged from the committee’s work was the duality between the study of Earth’s climate – which is complicated on scales ranging from centimetres to the size of the globe,” said Prof John Wettlaufer, a physicist at Yale University in New Haven, US.

Prof Wettlaufer explained that the Italian physicist was “building from the chaos and volatility of complex systems at [the level of] their tiny elements.” Syukuro Manabe’s study, on the other hand, “is knitting together the components of different processes to anticipate the behavior of a complex physical system.”

Prof. Hasselmann’s research included both the microscopic and macroscopic realms, according to the Yale physicist.

“Even if the reward is split between the climate and disorder halves, they are inextricably linked,” he stated.

Dr. Martin Juckes, deputy head of the UK’s Centre for Environmental Data Analysis (CEDA) and head of atmospheric science and research, said: “It’s incredible to see climate scientists’ work honored with the Nobel Prize in Physics today. Climate scientists are still being challenged by the complexity of global systems, which is heightened by the possibility of a climate crisis.”

The Royal Swedish Academy of Sciences held a press conference to reveal this year’s physics laureates. Manabe and Hasselmann will receive half of the ten million krona, while Parisi will receive the other half.

Alfred Nobel, a Swedish entrepreneur, established the awards in his will, which was written a year before his death in 1896.

Since its inception in 1901, the physics prize has been presented to a total of 218 people.

There have only been four female Nobel Laureates. John Bardeen, a scientist, received the prize twice, in 1956 and 1972.