He was awarded the Nobel Prize at the age of 90 for his research more than 50 years ago, and his achievements affect everyone

Text | "China Science News" reporter Han raised eyebrows

"In recent years, such hot searches have appeared frequently: the temperature has reached a record high for several months; This year is the hottest; In 2024, there will be the hottest dog days in 63 years...... Is it the 'hottest' every year? ”

"There's a good chance you'll hear something like that every year in the future – 'this year is the hottest year.'"

In the face of reporters' questions, Wei Ke, a researcher at the Institute of Atmospheric Physics of the Chinese Academy of Sciences, answered humorously and seriously.

Today, most of the public knows that greenhouse gases are the main culprits behind global warming, and they also feel that the weather is getting hotter every year. But thirty or forty years ago, predictions of higher temperatures due to increased carbon dioxide concentrations were not accepted by most scientists. The Japanese-American scientist Shuro Manabe, who came to the conclusion more than 50 years ago that "carbon dioxide doubles and the climate rises by 2.4°C", was not awarded the Nobel Prize in Physics until 2021, when he was 90 years old.

Why is our planet warming, why is the increase in carbon dioxide concentration the main cause of global climate change, and how does Shuro Manabe quantify the predictions? Recently, the book "Climate Warming and the Future of Mankind" was introduced and published in China, which was derived from the transcript of a lecture given by Shuro Manabe when he taught a graduate course at Princeton University in United States, in which he elaborated on the issue of climate warming.

Scientists who rely on talent and efficiency

Shuro Manabe, who won the Nobel Prize at the age of 90, is not a late-blooming scientist, in fact, he made quantitative predictions of climate change when he was in his 30s. "He's a very sharp scientist, and he's very efficient." In the preface to "Climate Warming and the Future of Mankind", Wu Guoxiong, an academician of the Chinese Academy of Sciences, commented on Manabe Shulang.

Wu Guoxiong believes that there are two types of scientists: one is a very diligent scientist who works more than ten hours a day; One is a scientist who relies on talent and mental acuity. Manabe Shuro falls into the latter category. From 1989 to 1991, Wu Guoxiong was a visiting professor at Princeton University in United States as a senior visiting professor, and Manabe was the advisor in charge of liaison and cooperation at that time. The two often eat together, and after eating, they will walk from the campus to the cafeteria. Wu Guoxiong said that Manabe Shuro swims and runs almost every afternoon, and his life is very regular, and he spends a lot of time on sports and life.

At Princeton University, there is an academic presentation almost every week, and Shuro Manabe attends. Every time Manabe Shuro sat in the first row, leaning back in his chair, sometimes with his eyes closed, looking like he was sleeping but in fact it wasn't, because the timing of his opening eyes and asking questions was very precise. "This is often the climax and essence of academic discussions at Princeton University." Wu Guoxiong said.

"The real man in life is more like the 'old naughty boy' in martial arts novels, humorous and innocent and cheerful, which brings a lot of happiness to everyone." Wei Ke, one of the translators of the book, said, "There is an anecdote about him circulating in his circle of friends, and it is said that after retirement, he did not like to be disturbed by other people's letters, so he made a stamp with the inscription 'Deceased' ('Deceased' and returned the letter with a seal." One can imagine how the person who received the return letter was crying and laughing. ”

Simplified models enable the "most complex" predictions

Shuro Manabe won the Nobel Prize in Physics for "physically modeling the Earth's climate, quantifying its variability and reliably predicting global warming." In the 60s of the last century, how did Manabe Shuro do it? He dealt with the extremely complex process of global climate change in a simple way, reducing the entire Earth's atmosphere to an 18-layer "single-column model" with limited calculations.

Wei Ke explained that there is only one point on the ground, extending upwards to the upper stratosphere, vertically divided into 18 layers, and only the vertical transport processes of solar radiation, longwave radiation, upward heat flux, and convection are considered. This extreme simplification captures the main process of the earth's energy balance, that is, the short-wave radiation obtained from the sun, and then through the long-wave radiation and various heat delivery processes, the energy is transmitted to the whole world, and finally the energy balance state of the earth-atmosphere system is reached.

The process of carbon dioxide inducing air temperature rise is to absorb the long-wave radiation emitted from the ground and cover the ground like a quilt, so that the earth cannot release long-wave radiation energy, resulting in the warming of the underlying atmosphere.

Manabe used three sets of simulation experiments to verify that the surface temperature is 15°C at a standard carbon dioxide concentration of 300 ppmV, which is similar to the global average surface temperature observation. As atmospheric carbon dioxide concentrations doubled to 600 ppmv, not only did the surface temperature increase by 2.4°C, but the entire troposphere warmed. Conversely, when the CO2 concentration was halved from 300 ppmv to 150 ppmv, the surface temperature decreased by 2.3°C. This is the first time in the world that the contribution of carbon dioxide to global warming has been quantitatively assessed.

Wu pointed out that the current climate model is basically based on the theory first proposed by Shuro Manabe. "It's just that the current model is not only single-column, but also affected by the advection process, and although there are differences, the overall result is very close to the early single-column model of Manabe Shuro."

Interestingly, around the time when Manabe established the 18-layer "single-column model", there was a debate among meteorologists around the world - from the measurements at the time, from the 50s to the 70s of the last century, carbon dioxide was steadily increasing, but the temperature was falling, which could not explain the "carbon dioxide caused the greenhouse effect", and some people even said that the earth was about to enter an "ice age".

However, this claim was quickly dismantled. Global industrialization is advancing by leaps and bounds, and the amount of greenhouse gases such as carbon dioxide and methane emitted into the atmosphere by human activities is large and fast, and assessment reports and studies on climate change have quickly made people realize that the climate is warming. Wei Ke said. Now, more than half a century later, the facts of global warming have proved Manabe's theory.

Action is more important

Rather than an exhaustive review of the literature on climate dynamics and climate change, Manabe's book focuses on the research he participated in and influenced the formation of his thoughts, giving readers an insight into the scientific journey behind understanding climate change.

Guo Chenyun, one of the book's translators and a researcher at the Institute of Atmospheric Physics of the Chinese Academy of Sciences, said: "If there is no significant change in energy production activities, the global average temperature is expected to rise by another 2 to 3 degrees Celsius in the 21st century." This will lead to more extreme weather and disasters, arid regions will be drier, and watery areas will see more river flows and flooding more frequent. ”

The world is full of uncertainty, but scientists predict a potentially definite fact. As a "hunter" to capture the "real culprit" of climate warming, at the Nobel Prize press conference held in Princeton in 2021, Manabe Shuro said meaningfully: "Formulating climate policies is often 1,000 times more difficult than making climate predictions." ”

In Weike's view, global warming has become an indisputable fact. "There is not much time left for humanity to 'waste'. Hopefully, Manabe's book will inspire those who are curious about how, why, and how the climate will change in the future. ”

"Climate Warming and the Future of Mankind", [American] Shuro Manabe, Anthony · Written by J. Brokoli, translated by Wei Ke, Guo Chenyu et al., published by Zhejiang Education Publishing House in August 2024, price: 109.9 yuan