Wang Ziwei 2020

Edit | Li Hongbing

Source | Yabuli Internal Reference

The consequences of climate change are endless all over the world. Extreme snowstorms hit the United States, Arctic sea ice melted, Indonesian capital Jakarta sank to the bottom of the sea, Australian mountain fires burned for months ... The impact of climate change on China is also very obvious.

What will happen in the future? Cai, director of The Lancet Countdown Asia Center and associate professor of the Department of Earth System Science in Tsinghua University, said that by 2060, there will be more and more climate crises in China.

Can emission reduction eliminate the climate crisis? Cai's answer is that China's carbon dioxide emission peak and carbon neutral action are very timely and important. They are to avoid long-term huge and unacceptable climate risks, but the climate system has inertia and the trend of climate change in the near and medium term is almost inevitable. In other words, before 2060, no matter how much China and other countries in the world reduce their emissions, whether they are carbon neutral or not, the probability of climate change will continue to intensify, and the trend of more extreme weather and rising temperatures will be hard to change.

Cai believes that in addition to promoting carbon neutrality at this stage, China must invest more energy in climate adaptation. If climate adaptation is not done well, the process of carbon neutrality will also be affected. In terms of climate adaptation, not only the government but also enterprises have great room for action, such as exploring the profit model of climate insurance in China.

Cities are concentrated areas of population and economy, and the importance of preventing climate crisis can be imagined. Then, how is the city's climate adaptation done, and can it resist the frequent and severe impact of the climate crisis?

According to Cai's research, the public and governments at all levels have not paid enough attention to climate adaptation. Many cities don't understand climate change, and they don't take the impact of climate change into account when making urban planning. Due to the lack of systematic assessment, it is difficult to make clear the vulnerability of cities in the face of climate crisis. "It's like you're going to war, but you have no idea what the enemy looks like. You're in the dark."

The following is Cai's conversation at Yabuli Forum:

Yabuli Forum: You mentioned in the 20021China The Lancet countdown report conference that China should take enough actions as soon as possible to avoid cascading health crises in the future. What is a chain health crisis? What was it like when it appeared?

Cai: First, climate change is not a traditional crisis, but a propeller and catalyst for many common crises. In the context of climate change, we will see more and stronger crises, such as high temperature and heat wave, extreme cold, rainstorm, flood, drought, typhoon, climate-sensitive infectious diseases (such as dengue fever and malaria) and so on. In the future, we may not face a single crisis, but a superposition of multiple crises in time and space, such as high temperature+dengue fever, high temperature+drought, rainstorm, flood and infectious diseases, resulting in1+1> The consequences of 2.

The second is a chain reaction. Natural crisis and social crisis are interrelated, and one crisis may trigger another, just like snowballing. Extreme rainfall such as "July 20" in Zhengzhou, in addition to the direct impact of casualties and property losses, may also have secondary effects such as traffic disruption, hospital power failure, and the decline of the whole society's ability to cope with the crisis and implement rescue, thus causing greater casualties and economic losses. Pay special attention to the chain reaction, which is also a challenge to the ability of urban governance.

Yabuli Forum: Do you mean that there will be more and more climate crises like the "July 20" torrential rain in Zhengzhou, and many climate crises may coexist at the same time and space, which will easily trigger a snowball-like chain reaction and impact the stable operation of the economy?

Cai: We must deeply understand what the average temperature rise of 1, 2,3 means. In the last 200 years since industrialization (1850), the global average temperature has increased by 1. 1. Unfortunately, the temperature in China is slightly higher than the global average.

If the temperature continues to rise, many people and industries will be hit hard. For example, during the period of 1986-2005, the number of heat wave days in Guangdong was 6 days, and in 2020, this number has risen to 25 days. If the temperature rises to 2, according to the prediction of domestic scholars, this value will become 120 days or so. This means that there is a heat wave every three days on average throughout the year, otherwise it is hard to imagine who can stand it. Agriculture, tourism and service industries will be hit hard, and hospital emergency will be overwhelmed.

Yabuli Forum: Are these climate predictions accurate?

Cai: People don't pay much attention to the results of climate prediction, but it is not terrible and deceptive. The current climate model can well reproduce the history of climate change, such as simulating the rising trend of temperature in recent years. Therefore, the future climate prediction results given by these climate models are also highly reliable, and we need to attach great importance to them.

Yabuli Forum: China is vigorously promoting emission reduction. If carbon neutrality is achieved at the peak of carbon dioxide emissions in 2030 and 2060 as scheduled, will the crisis caused by climate change be significantly improved?

Cai: There won't be much change before 2060. At present, almost all models in the world believe that the trend of climate change (at least temperature rise) will not change much before 2060, regardless of the emission reduction efforts of China and other countries in the world and whether they are carbon neutral. In other words, climate change will continue to intensify in the near and medium term, and the trend of increasing extreme weather and rising temperature may be difficult to change.

Only after 2060, according to the intensity of emission reduction in recent years, the global climate change trend will be significantly different. In recent years, emissions have been reduced more, and the range of climate change will be smaller after 2060. On the contrary, climate change will be more serious.

Yabuli Forum: Why will climate change become more and more serious and climate disasters increase before 2060, even if emissions are substantially reduced?

Cai: First of all, the climate system has inertia. At present, the general trend of climate warming will not be reversed in the short term because of emission reduction in recent years. It will take 30 to 40 years from emission reduction to real climate impact. In other words, our current actions will not have a significant impact on the climate until 2050 or even 2060. Second, climate change is a global problem, which is much more difficult to control than local problems. If other countries do not cooperate, it is not enough for China to do well.

But it doesn't mean that it is meaningless to reduce emissions now. On the contrary, if we want to avoid long-term huge, unacceptable and irreversible climate risks, we must act in advance. Therefore, China's carbon dioxide emission peak and carbon neutral action are very timely and important. On the other hand, because the trend of climate change in the near and medium term is almost inevitable, we must not ignore the adaptation of climate change at this stage, and we should invest more energy in adaptation.

Yabuli Forum: How is the climate adaptation in China now? Can you prevent the future climate crisis?

Cai: At present, the public and governments at all levels have not paid enough attention to climate adaptation. Many people and managers don't know what kind of climate change will happen in the next 30 to 40 years, what challenges it will bring to everyone's health and the smooth operation of social economy, and how to carry out adaptation actions. If we just passively wait for the occurrence of climate disasters and then go to disaster relief, we will inevitably bear many avoidable losses.

Yabuli Forum: The "July 20" rainstorm in Zhengzhou is a manifestation of climate change. What are the shortcomings of climate adaptation exposed by it? What can other cities in China reflect on?

Cai: Do you know that the drainage system in most cities in China is based on the rainfall standard of once every few years? This is an annual rainstorm. Not to mention 50 years, 100 years, the drainage system of Liancheng city has not been designed according to the return period of a rainstorm in three to five years. I don't know where the next rainstorm will fall, but if the urban infrastructure and drainage capacity are roughly the same, how much better will waterlogging be than Zhengzhou?

Many cities don't understand climate change, and they don't take the impact of climate change into account when making urban planning. But the new normal we are facing is that by 2060, climate change will become more and more serious, and there will be more and more climate disasters.

This long-term trend will pose new challenges to important infrastructure such as roads, bridges, subways and hospitals. Local governments must measure whether the existing infrastructure and resource allocation can cope with the risk of once in a hundred years or even once in a thousand years, and whether they can early warn, monitor and prevent major disasters.

Yabuli Forum: In 20 17, China started the construction of a climate-adapted city with 28 pilot projects. However, some experts believe that there are few targeted climate adaptation measures in pilot cities, or all the routine tasks they have to do are included, and finally those tasks can be set anywhere. In other words, the real climate adaptation in some pilot cities is far from ideal.

Cai: I really heard that. This just shows that people generally lack understanding of climate adaptation and don't know what to do.

Yabuli Forum: What do you think cities should do now to prevent future climate crisis?

Cai: The most crucial step is to understand the impact of climate change on your city and analyze the vulnerability when the climate crisis occurs. In this regard, every city still has a lot of room for improvement. If you don't even know your "family background", how can you adapt to the climate and plan ahead?

Yabuli Forum: What is the "family background" of China city and what are its vulnerabilities in the face of climate crisis?

Cai: It's hard to say now because we lack evaluation. For example, climate change and health can only be studied quantitatively according to the impact of past events on health. But what will happen in the future, how the incidence of various diseases will change, and how medical resources need to be allocated in advance, many problems are unclear. It is equivalent to fighting a war, but you have no idea what the enemy looks like and you are in the dark.

The upcoming National Climate Change Adaptation Strategy 2035, I think its ideal state is to put forward clear work goals and quantitative indicators for the future, but if the current foundation is not clear, it is difficult to put forward goals and indicators.

Yabuli Forum: Indeed, without systematic arrangements, it is impossible to know where there are loopholes and risks, and naturally it is impossible to know what will happen in the future. It can only be estimated based on past experience.

Cai: Right. At present, many scholars have been studying the future climate risk, but their work is scattered and lacks systematic design and arrangement to some extent. For example, some people only study high-temperature heat waves, while others only study floods. These two waves not only used different climate scenarios and research methods, but also used different scenarios to estimate the total number and distribution of vulnerable groups. Most of the existing studies are difficult to answer "What kind of climate risk threats will China face in the future?" "Where are our shortcomings?" Wait for questions.

Therefore, risk assessment needs attention at the national level, and some developed countries make a comprehensive assessment every five years.

Yabuli Forum: How do developed countries adapt to the climate?

Cai: Britain is typical. Almost 20 years ago, Britain began to systematically assess the impact of climate change, analyze its vulnerability, formulate a climate adaptation action plan, and then regularly track and monitor the implementation effect of the action plan, and then start a new round of assessment, re-examine and fill the gaps, which is cyclical.

Generally speaking, developed countries are less affected by climate change than developing China countries, but developed countries attach great importance to climate adaptation and invest a lot of money for it, which is equivalent to forming a protective cover for their own countries. However, many developing countries are not fully aware of the problem of climate adaptation, and they are not fully prepared for disaster response mechanisms and inter-departmental coordination.

Moreover, emission reduction has certain externalities in economics, because its beneficiaries are not specific, but if we do more climate adaptation, our country and region will benefit more, which is equivalent to buying insurance for ourselves.

Yabuli Forum: Now, the eyes and resources of the whole society have been mobilized by carbon neutrality. In contrast, what value can climate adaptation create for society? What can enterprises do for climate adaptation?

Cai: The core of climate adaptation is to reduce the loss and impact of climate change. Therefore, where there are losses and impacts, there is a need to adapt to the climate, and there are opportunities and benefits to avoid losses. Therefore, enterprises have a lot of room for action.

First of all, the profit model level. We need to find an economic means to stimulate people to make long-term decisions, from passive disaster relief to active disaster prevention and mitigation. Climate insurance can be a fulcrum to incite change. Why do local governments lack the motivation to deploy disaster prevention and mitigation in advance? There must be many reasons, one of which may be that although every major disaster has caused huge economic and people's lives and property losses, it can always get a lot of money and material assistance from the central government. For an extreme example, suppose that in the future, local governments will have to bear all the disaster losses themselves, and at the same time, they will have to go to insurance companies for insurance, and the effect may be completely different.

There is a "principle of promoting loss prevention" in the calculation of insurance rates. The better the disaster prevention work, the lower the rate and the less the premium paid. Conversely, the higher the premium. In this mode, local governments are more motivated to put the concept of disaster prevention into the whole urban planning, such as improving the defense standards of sewers and strengthening dams.

Climate insurance in China is still in its infancy. In the face of more and more serious and frequent climate disasters, it is very urgent to give full play to the role of the insurance industry in dispersing climate risks and explore the profit model of China's climate insurance, which can not only alleviate the pressure of the central and local governments to provide disaster relief funds afterwards, but also effectively improve the disaster prevention and mitigation capabilities of various regions.

Second, the service level. Industries and regions that are greatly affected by climate change will generate new demands, such as fresh ocean transportation, which requires very high time and temperature. It is necessary to accurately predict the meteorological conditions on the way, avoid the storm at sea, and choose the fastest route to save fuel. Providing these customized meteorological services is also a very new form. In addition, each city and community has different basic conditions and different climate impacts, which requires various tailor-made climate adaptation programs.

Third, the technical level. Agricultural water-saving irrigation, drought-resistant and insect-resistant seed breeding, urban drainage pipe network transformation, marine river and lake dam upgrading, green roof construction, early warning and monitoring equipment installation, etc. Are technical means to adapt to climate change.

Yabuli Forum: You just mentioned that doing a good job of climate adaptation will help to achieve carbon neutrality. How to understand the relationship between the two? Now, all eyes are focused on carbon neutrality. In this context, how to understand the urgency and necessity of climate adaptation?

Cai: Whether climate adaptation and carbon neutrality can be better coordinated needs to be explored. After all, the carbon-neutral strategy has not been announced for a long time. Moreover, both of them need capital investment, and in the case of limited funds, they may squeeze each other and compete for resources. But in the long run, climate adaptation and carbon neutrality must find a good way of cooperation, otherwise it may not be done well.

Yabuli Forum: Why?

Cai: First of all, if the city can't adapt to and cope with frequent climate disasters, it will lead to the repeated construction of infrastructure such as bridges, roads and houses, which will inevitably increase carbon emissions. Secondly, it is difficult to achieve carbon neutrality only by existing technologies, and subversive emission reduction technologies must be developed. Enterprises need a relatively stable environment to develop such technologies, and climate disasters will just destroy the stable operation of social economy, making it difficult for enterprises to make long-term layout. Therefore, if climate adaptation is not done well, the process of carbon neutrality will also be affected.

Editor Zhang Weisheng.

Typesetting Wang Ziwei