Science around: Tipping point

　　China Xiaokang Network Exclusive Article

　　Wen | Yin Chuanhong

　　In nature's complex systems, tipping points abound, because the dynamic process of its development is extremely unstable and often has a potential critical state. Even, it is possible that when a certain critical value is reached, it is not enough time for people to judge risks, and it is not possible to issue a timely and valuable warning, which triggers a sudden and dramatic change.

　　Not long ago, more than 14,000 scientists, who signed an initiative to declare a global climate emergency, renewed their call for immediate action to address the climate emergency, warning that the climate has embarked on "alarming and unexpected operating patterns" and that multiple climate tipping points are looming.

　　All economic activities and all living things depend on the Earth's ecosystem – different species coexist and influence each other and each other and their habitats.

　　The situation is indeed grim. Since 2019, global climate-related disasters have "increased as never before", as we often see in news reports: ferocious and abnormal floods, record-breaking heat waves, earth-shattering hurricanes, wildfires raging everywhere, and even unprecedented "desert rainstorms", where "water depth" but "hot" "drama" is pouring in.

　　More heart-wrenching data shows that Greenland and Antarctica have recently seen their lowest ice levels, with glaciers melting 31 percent faster than they did 15 years ago. Forest degradation caused by fires, droughts and logging has caused parts of Brazil's Amazon rainforest to emit more carbon dioxide than absorbed. Tim Renton, director of the Institute for Global Systems Studies at the University of Exeter in the UK, said: "The evidence that humanity is approaching a climatic tipping point is already there and we have to respond to it. ”

　　For many environmentalists and ecologists, these tipping points are worrying. Projections show that if emissions are not controlled in the coming decades, we will cross the irreversible tipping point of permafrost melting and losing the Greenland ice sheet and other factors. It also underscores a growing consensus that man-made global climate change is the most serious environmental problem of our time. This has never been an isolated scientific study, it is about the common interests of mankind, and no country can really stay out of it.

　　I remember that at the beginning of the new century, there was a debate in the academic circles: Is the environment an integral part of the economy, or is the economy a component of the environment? Economists see the environment as a subsystem of the economy, while ecologists, in contrast, see the economy as a subsystem of the environment. From the perspective of an ecologist, the conflict between the economy and the earth's natural systems has always existed. If the operation of the subsystem economy is not coordinated with the large system, the earth's ecosystem, it is bound to lose both sides.

　　It is clear that all economic activity and all living things depend on the Earth's ecosystem – different species coexist and influence each other and their habitats. Millions of species live in complex equilibrium, intertwined through food chains, nutrient cycles, hydrological cycles, and climate systems. An economy that sustains the environment, the ecological economy, requires that the formation and operation of economic policies be based on the framework established by ecological principles.

　　It is true that the services provided by ecosystems to humans and their value may seem difficult to assess, but the fact that such a fact is clear to us: there is a natural equilibrium. Natural ecosystems regulate many of the gases in the atmosphere, which in turn alter temperatures, wind patterns, and precipitation. As the famous American biologist and naturalist Edward Wilson pointed out, the rainforests of the vast Amazon River Basin "produce" half of this rainwater. When forests are largely cut down, the water supply is reduced accordingly. The mathematical model of precipitation and evaporation cycles already shows that green cover has a critical critical area below which forests are bound to be insecure.

　　In fact, in the various complex systems of nature, such tipping points abound, because the dynamic process of its development is extremely unstable and often has a potential critical state. Even, it is possible that when a certain critical value is reached, it is not enough time for people to judge risks, and it is not possible to issue a timely and valuable warning, which triggers a sudden and dramatic change. Isn't the critical state "at risk", the margin of safety, or even the brink of collapse?

　　The global challenges facing humanity today are perhaps more serious than at any other time in history. The choices we make will determine our ultimate destiny.

　　("Xiaokang", China Xiaokang Network Exclusive Special Article)

　　This article was published in the early September 2021 issue of Xiaokang