Tisch
Global climate change response
[Abstract] The limited results of Doha Conference show that the global efforts to deal with climate change are facing great difficulties and have fallen into the lowest point since 1988, when the international community started the negotiations and response procedures related to climate change. The reason for this phenomenon is that all countries regard cost-benefit balance as an important decision-making basis for participating in the international climate change response framework and mechanism. Specifically reflected in the participation degree of carbon emission coverage, carbon emission coverage has become a key factor affecting the response to global climate change. By constructing a theoretical model of cost-benefit balance, this paper demonstrates the double equilibrium equation of global climate change response framework and mechanism development, and points out that the current international efforts to deal with climate change are still in a relatively stable low-income level equilibrium state. Obviously, in the global response to climate change, there must be a high-level equilibrium point that can bring high income and high welfare. The difficulty facing the international community now is how to find and determine the critical point from the low-level equilibrium point to the high-level equilibrium point and achieve a breakthrough, so as to promote the participation of all countries and push the international efforts to deal with climate change to the high-level equilibrium point.
[Keywords:] cost-benefit analysis of the equilibrium point of the international framework on climate change
【 China Library Classification. ]P476
[Document ID ]A
[ArticleNo.]1006-1568-201304-0042-15
From 1988, the first semi-official climate conference held by the international community in Toronto, Canada, to 20 18/cmp8, the Doha meeting of the United Nations Framework on Climate Change, international negotiations on climate change have gone through 25 years. The Toronto meeting put forward the carbon emission reduction target to deal with climate change, that is, based on the emission level of 1988, the global emission reduction will be 20% by 2005, which is historically called the "Toronto target" to deal with climate change. Now it seems that this goal is obviously too idealistic. Because the final resolution adopted at the 20 12 Doha Conference does not have a clear global carbon emission reduction target, more words are "hope", "rationality" and "voluntary". This means that after 25 years of efforts, although the global carbon emission level has been much higher than that of that year, the willingness and progress of the international community to deal with climate change and carbon emission reduction can be described as not advancing but retreating. Therefore, it is necessary to summarize and review the existing specific coping strategies, especially the theories that guide the international community to cope with climate change.
To answer this question, we must first understand the decision-making basis for countries to participate in the global climate change response framework and mechanism. It is generally believed that the effectiveness of the climate change response framework fundamentally depends on the participation of all countries. It is precisely because the resolution must reflect the participation of all countries to the greatest extent that the international community can finally reach one resolution or another. Therefore, as an important milestone of global climate change, the original Kyoto Protocol (hereinafter referred to as the Protocol) set its entry into force condition as 55% of the emission ratio, that is, at least enough countries and regions on the list of Annex I countries joined the Protocol before its terms could really take effect.
It should be pointed out that all countries are determined to participate in the cost-benefit calculation of participating in global climate change governance; In other words, cost-benefit calculation is the decision-making basis of climate change diplomacy in various countries. For example, when discussing the voting protocol, the US Senate said that "any international agreement on climate change will inevitably have a series of financial and economic impacts on the domestic economy". Specifically, the so-called "economic and financial impact" actually refers to costs and benefits, that is, what benefits will be brought to the United States by joining international agreements related to climate change and what costs will be increased at the same time. In other words, the United States can only make a judgment and decision on whether to join the Protocol after making clear such a cost-benefit relationship. In this regard, at a hearing on climate change in the US Congress, the participating senators explained why the United States has not yet joined the international climate change agreement, "because the United States has not yet figured out the various impacts of international climate change agreements on the domestic economy."
Based on the above logic, this paper will take the cost-benefit analysis as the starting point to analyze why the current global climate change governance mechanism is stagnant, and think that this situation is precisely the low-level equilibrium of countries' participation in global climate change for cost-benefit considerations. Based on the optimistic judgment that there is a higher level of balance, this paper holds that the international community needs to further promote the participation of all countries to make the international efforts to deal with climate change move towards a higher level of balance.
First, the cost-benefit calculation of the global climate change response framework.
The cost-benefit analysis of the global climate change response framework in international academic circles is mainly calculated by establishing various economic models, among which the more representative method is the general equilibrium economic analysis method. The economic growth, energy utilization, carbon emissions, climate change patterns, climate change impacts and various carbon emission reduction and climate change adaptation policies in a certain period, such as 2055 or 2 100, are brought into the model as variables, and each variable is demonstrated in various ways, so as to calculate the carbon emission price under different emission and emission reduction scenarios, and the resulting costs and benefits.
Taking the research of DICE (Dynamic Comprehensive Climate Economy Model) as an example, this paper analyzes the cost-benefit of Copenhagen Accord (1) reached by the international community in February 2009. In this model, there are three bases for calculating costs and benefits:
First of all, under the path of climate change response agreed in Copenhagen, the global and national direct net losses caused by climate change actually include both costs and benefits.
Second, under the Copenhagen Accord, the cost of emission reduction expenditure brought by the emission reduction paths and policies set by the world and countries is closely related to the provisions of the Agreement, including technological change, economic growth and social welfare.
Thirdly, under the Copenhagen Accord, according to the carbon emission price simulated by the author through the same model, including the transaction of carbon tax and carbon emission rights, and the extra carbon emissions that countries need to buy in order to reach their respective carbon emission quotas, finally, the cost of paying extra carbon emission quotas for the whole world and countries is calculated. It should be pointed out that due to the uneven distribution of carbon emission reduction quotas among countries under the Copenhagen Accord, there will be two situations: "surplus" and "shortage" considering the differences in emission reduction capabilities among countries, so this cost is positive for some countries and negative for others. Of course, globally, the total amount is zero.
According to this calculation framework, William William D. Nordhaus. Nordhaus concluded that by 2055, the total direct expenditure on global climate change under the Copenhagen Accord will be $65,438 billion+647 billion euros. Is this expenditure level high or low? In the early stage of the same series of studies, nordhaus used the same model to calculate the expenditure cost under various climate change response scenarios. He divided the total expenditure into two parts according to its nature. The first part is the loss of climate impact and the cost of emission reduction. The comparison results are as follows: from the low cost in the optimal response scenario to the high cost in the scenario of taking no measures and setting too high emission reduction or temperature control targets; The second part of the expenditure comes from the purchase of carbon emission quotas, in which the carbon emission price determines the final purchase expenditure, and different climate change response scenarios mean different carbon emission prices. The author ranks them, and the results show that the more radical the strategy to deal with climate change, the higher the price of carbon emissions that the international community can bear in the future, which means that different countries must pay higher costs for purchasing additional carbon emission quotas in order to achieve emission reduction targets.
It is worth noting that, due to the great uncertainty of scientific research and socio-economic development, economists such as nordhaus and climate change research groups such as IPCC and stern review may not be completely accurate when calculating the costs and benefits of global climate change response. However, judging from the sequence of different scenarios, their conclusions are logically valid, that is, the international community will bear different costs and benefits in response to different climate change response and development scenarios. So from the perspective of cost-benefit, how can we further understand the main differences between different climate change response and development scenarios? What are the key factors that affect the cost and benefits of the global climate change response framework? Understanding these problems will help to establish a cost-benefit model of international climate change response in the economic sense.
Second, carbon price, participation and cost-benefit analysis
According to nordhaus and Richard Tolle's analysis of the economic impact of climate change, the net cost impact of climate change mainly comes from three sources, namely, the direct impact of climate change, the impact of carbon emission reduction procedures and the impact of carbon emission prices. For the whole world, the impact of the first two sources is generally reflected in the positive net cost, while the impact of carbon emission prices on the net cost is nominally zero after mutual cancellation between countries. But in fact, there are two sources of global carbon emission price: carbon tax and carbon trading. If all carbon prices are reflected in the form of carbon tax, then the carbon emission price in an equilibrium state should be equal to the marginal cost of carbon emission reduction, that is, a country pays the cost for carbon emissions exceeding the quota. If the global loss caused by climate change is further included in the calculation range of carbon emission price, that is, the external impact of climate change is completely and fully internalized into the carbon price, then the carbon emission price can become an indicator to measure the cost-benefit of the global climate change response framework. In this regard, under different global climate change response frameworks, various carbon prices will be generated, reflecting the net cost level paid by the world for these different climate change response frameworks.
If the carbon price is given a new meaning, that is, the impact of climate change and carbon emission reduction expenditure are converted into carbon emission price, and then the carbon emission price is used as a symbolic indicator to measure the cost-benefit of the global climate change response framework, then the cost-benefit comparison results obtained on the basis of general equilibrium can be recombined and rearranged. Taking nordhaus's 15 climate change response scenario as an example, in a given period, other conditions unchanged, 15 scenario can be rearranged into a map 1. This new arrangement shows that no matter what emission reduction strategy and path the international community adopts, it will gradually rise from the initial lowest point only in time series. However, if cross-sectional comparison is adopted, the differences between different scenarios will be clear at a glance. According to the previous analysis, the difference of carbon emission price actually represents the difference of costs and benefits of various climate change coping mechanisms.
From figure 1, we can draw a basic conclusion that the higher the price of carbon emissions caused by climate change coping mechanism, the higher its cost. For example, compared with the agreed coping mechanism, the coping mechanism that can control the global temperature rise in the range of 2 ~ C is obviously more expensive; At the same time, an agreement that can cover US carbon emissions is more expensive than an agreement that does not include US carbon emissions.
If we further compare various coping scenarios that lead to the price of carbon emissions, we can find that the biggest difference of various coping scenarios lies in the different participation of countries, or the different coverage of global carbon emissions. Therefore, it can be considered that participation is an important factor in determining the price of carbon emissions and the cost-benefit level of coping mechanisms.
Whether it is the response mechanism of the protocol or setting a temperature rise limit of 2℃, its essence is the coverage of global carbon emissions. In absolute sense, the greater the coverage of the coping mechanism, the higher the price of carbon emissions, although the response results will be more effective. But the problem is that in the international community, the coverage of the response mechanism does not depend on the price of carbon emissions or the effectiveness of the response, but on the degree of recognition of the mechanism by countries, which is reflected in the degree of participation. Officially, participation can be divided into three categories: participation, non-participation and conditional participation. Take the attitude of countries towards the Protocol as an example. The United States has the conditions to participate, the European Union will participate, and developing countries such as China and India will not participate. Take the Copenhagen Accord as an example, both China and India have joined the camp of conditional participation. It should be pointed out that it is relatively more complicated to measure the participation from an unofficial perspective, because the participation of a market, a department or a region may be inconsistent with the official statement, resulting in changes in the actual participation, and the carbon emission price finally formed by the market reflects the actual participation. In this way, the vertical axis in figure 1 can be changed to "participation", and then the differences between different coping mechanisms and scenarios of 15 can be observed in different ways. From the lowest participation to the highest participation, the coping mechanisms and scenarios with different characteristics are determined.
Applying the above-mentioned relationship between participation and coping mechanism to the practice of global climate change coping mechanism, and selecting several important nodes from the negotiation of international climate change coping mechanism in 1988 to the end of Doha Climate Conference in 20 12, we can find that the differences and changes of countries' actual participation in climate change based on carbon emission coverage determine the fluctuation of coping mechanism and objectives.
In Figure 2, although the response scenario of controlling the temperature rise of 2℃ requires a high degree of participation close to 100%, this is confirmed by the Copenhagen Accord. However, this goal has not been specifically implemented. In the Copenhagen Accord, the coverage of global participation in carbon emissions did not increase, but decreased due to the mechanism of resource emission reduction. So from 1988 to now, the participation of global climate change response mechanism has been decreasing. In the same period, the carbon price in the international market also continued to decline, further indicating that the overall will of the international community to deal with climate change and carbon emission reduction is weakening, which confirms the evolution of the assessment of the net cost level by the climate change response mechanism based on the cost-benefit measurement method at different stages.
Thirdly, the cost-benefit model of global climate change framework.
This section will study the cost-benefit model to deal with climate change. In the following functions, cost refers to total cost, benefit refers to total income, Y refers to total output or welfare level, mitment refers to countries' participation or carbon emission reduction commitment level in different periods, and ert refers to the discount degree in different periods.
A cost function: Cost =∑fmitmentiert；;
In view of technological progress, climate change trends, economic development and other factors, the present value of the cost of climate change cooperation in the international community depends on the participation or commitment of all countries. The existing research shows that with the increase of national participation, the international community will pay more incremental costs in the initial stage of participation in the case of low participation, while the increase of costs will slow down in the later stage in the case of high participation. In other words, the curve of the cost function will be increasing and convex, that is, first fast and then slow, that is, the cost curve in Figure 3. In the end, if all countries in the world participate in the cooperation framework, the cost will be fixed at a certain peak and will not increase indefinitely. This is because once an effective global cooperation mechanism is established to control carbon emissions and the global temperature change is controlled within a tolerable range, the price of carbon emissions will not continue to increase, as shown in Figure 3, and the cost of coping will tend to stagnate.
2. Income function: benefit = ∑ fmitmentiert;
Similarly, considering other conditions, the benefits of international cooperation to deal with climate change also depend on the participation of all countries. According to relevant research and the above analysis, increased participation will bring more benefits to the world. Of course, the characteristics of the income curve are different from those of the cost curve. First of all, in the early stage of low participation, because of the "leakage" effect, the global income growth rate brought by improving the level of cooperation is slow; Once the cooperation level reaches a certain level, with the "leakage" effect significantly reduced, the effectiveness of global carbon emission-related policies will also be significantly improved, such as carbon tax and carbon trading. At this time, the world will gain greater benefits from cooperation and see rapid growth; This means that the overall yield curve will show an increasing trend from slow to fast, as shown in Figure 3.
The second important feature of the income curve is that in the initial stage, due to the low participation of countries, the income level of the corresponding international framework will be lower than the cost level, and in some extreme cases, the income will even be negative. However, with the deepening of countries' participation, the income curve will climb at a faster speed, and will exceed the cost curve after reaching a certain degree of participation. This level of participation is also a balanced participation.
There is also a third feature of the income function, that is, after the participation is further improved, the growth rate of income is likely to decrease, that is, the growth rate will slow down and gradually approach the income curve in Figure 4, which will change the income curve as shown in Figure 4. This will change the relationship of the cost-benefit curve, and there will be two equilibrium points. The first equilibrium point Q 1 can be called low-level participation equilibrium, and the second equilibrium point Q2 can be called high-level participation equilibrium.
Triple equilibrium condition
First, when the cost curve is higher than the income curve, it is called "insufficient participation". At this time, the world will pay a net cost for it, thus promoting the continuous improvement of participation until the two are equal;
Second, when the cost curve is lower than the income curve, it is called "excessive participation". At this time, the world will gain net benefits from a higher level of coping participation. Despite this, the participation will not continue to increase, but will develop in the opposite direction, that is, it will drop until the net income is zero. This is mainly because, when the participation is too high, on the one hand, the increase of the net income of the climate change response department itself will weaken the enthusiasm of countries to continue to invest and participate in this field, which is highlighted by insufficient investment in other departments and excessive investment in the climate change response department; On the other hand, although the global total income continues to increase, the distribution of income is obviously unbalanced in different regions, so various political and economic obstacles will also be formed and increased to further improve participation and obtain more net income.
Third, the comparison of the two equilibrium levels. According to the above analysis, if the benefit curve of global climate change is simulated, the result will be concave first and then convex. Compared with the fixed cost curve, this leads to two equilibrium levels: one is low and the other is high. When the equilibrium condition is established, both equilibrium levels can help the international community achieve the optimization of "participation". In other words, at these two levels of participation, at least within the climate change response department, it is enough to form a relatively stable state. But obviously, although the balance of low-level participation has achieved departmental stability, its benefits to global total output and total welfare are lower than those of high-level participation.
Four double equilibrium conditions: Y=∑fmitmentiert
Starting from the third point, it is necessary to introduce the fourth condition, that is, to consider the general equilibrium condition of the output of two departments. If countries' participation in climate change response is included in the overall welfare consideration, participation will affect the internal cost-benefit balance of climate change response departments, and then affect the cost-benefit balance of other departments, and ultimately affect the overall welfare level. At the current level of scientific cognition and development stage, participation in climate change response has an increasing impact on the present value of the total welfare of economic growth. However, based on the existing general equilibrium analysis, it is reasonable to think that participation in climate change response does not always increase the total economic welfare, because after participation is above a certain level, no matter how the net welfare within the climate change response department changes, it will have a negative effect on the total economic welfare, thus leading to the reversal of the existing cost-benefit relationship, as shown in Figure 5.
In this way, the two kinds of balanced participation have different welfare effects. Low level of balanced participation leads to lower output level, while high level of balanced participation leads to higher output level. Judging from the output level, the former is a low-income equilibrium, not an ideal result, while the latter can bring better welfare. The development of global climate change response is actually a process of seeking cost-benefit balance and achieving a higher output level. Generally speaking, the current international climate change response framework is closer to the equilibrium state of low income, that is, countries "freely" decide to participate on the basis of their own cost-benefit accounting, which was initially confirmed at the Doha Climate Conference in 20 12, and then summarized in 20 15, forming a new international response framework, further strengthening and fixing the internal balance of the climate change sector.
From a global perspective, this equilibrium is not optimal. As shown in Figure 5, if the participation is increased, the overall output and welfare level will be higher. The problem is that once the balance of low-income participation is rapidly strengthened or even fixed after it is established, it is difficult to break this balance, promote participation and achieve a more optimized output and welfare level. There are two possible situations that will promote this breakthrough.
First, changes in external conditions, such as the intensification of climate change, the increase of international preference for climate change, the improvement of recognition of countries' response to climate change and technological progress, will simultaneously increase the costs or reduce the benefits of different participants in coping with climate change, thus pushing the cost curve up or the benefit curve down, forcing the optimal balanced participation to extend to the right. After this situation changes relative to the external conditions, the valuation level of the climate change response department has improved, thus improving the relative value of various inputs, so that participating in the climate change response process can bring lower opportunity cost and higher total output and welfare.
Secondly, there is the possibility of endogenous mechanism to promote the increase of participation, and the most important thing is the demonstration effect brought by participating countries/regions/departments. In the real world, the participation of countries/regions/departments in climate change response is extremely uneven, some are spontaneous, and some are just following. In this way, the participation itself may change slightly: mainly due to various endogenous reasons and incentives, the participation will continue to increase, which will bring benefits and costs. Once participants get net benefits from it, they may form a demonstration effect on other non-participants, thus attracting more participants. Of course, as mentioned above, considering the equilibrium conditions, the additional net income generated by the higher participation caused by the demonstration effect may not necessarily promote the continuous increase of participation in the initial stage, but may reduce the participation to the equilibrium level. However, there is a tipping point, that is, after some key countries/regions/departments join the climate change response procedures or implement some landmark emission reduction policies, the increase in participation will be difficult to reverse, thus accelerating the convergence to the next equilibrium point, that is, the high-income equilibrium level, and gradually stabilizing at this equilibrium point.
Based on the law of diminishing marginal output of participation, the output function has an important assumption, that is, 100% participation may not necessarily lead to the maximum output. As pointed out in the IPCC Fourth Assessment Report, the international community is faced with a variety of alternative emission reduction scenarios, ranging from "business as usual" to the most active response scenario, and the ranking is only from the lowest participation >: =0 to the highest participation.
Fourthly, the application of the model
The above theoretical model analysis has two important explanatory significance for the current international practice in dealing with climate change. On the one hand, the development path of the international climate change response framework will be restricted by the following two situations: first, it will move along the net income curve within the department, and with the increase of participation of countries around the world, the net income of the international emission reduction response framework will change accordingly. Fig. 6. Based on the existence of double equilibrium, the curve will be inverted U-shaped, with two intersections with horizontal participation, Q 1, Q2, which means that possible participation will only be maintained. Secondly, in order to achieve equilibrium, Q 1 and Q2 are still the most likely selection results after stabilization. Therefore, the climate change response framework measured by participation level will fluctuate around these two points. At the same time, under the influence of internal and external conditions, the transition can be made between two points. In other words, the choice of final participation will be limited between Q 1 and Q2.
On the other hand, the above constraints are also in line with the current realistic choice of countries to deal with climate change. First, all countries/regions/departments participate in the climate change response framework to varying degrees, which is finally reflected in a moderately balanced level of participation on a global scale. = Q & lt=Q2, which better explains that some carbon emitting countries have actually participated in the global climate change response process through voluntary emission reduction, although they have not formally joined the relevant international climate change response and emission reduction framework. On the one hand, the endogenous emission reduction demand from these countries/regions/departments based on their own costs and benefits, on the other hand, it is also promoted by other countries/regions to deal with climate change and emission reduction to some extent.
Second, the fact that the international community has made slow or even retrogressive progress in dealing with climate change in the past 25 years shows that from the perspective of general equilibrium, although the increase of participation is conducive to the improvement of output, the degree of response depends on the balance of costs and benefits within the department. Before the critical critical point is broken, it is still difficult for the international community to jump out of the level of low-income balanced participation in dealing with climate change. In this way, it is reasonable for countries to show various positive or negative policy fluctuations.
Third, if the international community wants to get out of the current climate change predicament and jump out of the low-level equilibrium, it must explore and study the key things that affect participation and their critical levels. Possible targets of criticism include: more accurate scientific research and understanding of climate change, greater climate disaster, more systematic social mobilization, more effective and feasible policy tools, and so on. Of course, if we want to find this critical substance and critical level, the world needs more trial and error to verify it.
Concluding remarks
If the progress of the global climate change response framework is measured by the participation of all countries, the fact that the results of the Doha meeting are limited shows that the efforts related to climate change response have almost come to a standstill, reaching the lowest point since the international community began to negotiate and design the framework from 65438 to 0988. Nevertheless, the analysis of the cost-benefit relationship in this paper shows that this low point may just reach the equilibrium state under the participation decision. However, this is a low-level equilibrium point, which can only bring low income and low welfare. In the process of global response to climate change, there is bound to be a high-level equilibrium that can bring high income and high welfare, that is, through a higher degree of participation in climate change, carbon emission reduction can be effectively realized, and at the same time, better efficiency, that is, output, can be obtained. Only by finding the corresponding critical point and achieving a breakthrough in the global climate change response framework can we ensure that we can jump out of the low-level equilibrium state and reach the high-level equilibrium state.