“当今世界通行的规则是，正义的基础是双方实力对等;同时我们也知道，强者可以做他们能够做的一切，而弱者只能忍受他们必须忍受的一切。”修昔底德(Thucydides)所著的《伯罗奔尼撒战争史》(History of the Peloponnesian War)中的这句话，可以说是唐纳德•特朗普(Donald Trump)政府的哲学。因此，他的两名顾问，赫伯特•雷蒙德•麦克马斯特(HR McMaster)和加里•科恩(Gary Cohn)，曾在5月写道：“当今世界不是一个‘全球社会’，而是各个国家、非政府行为体和企业打交道并争夺优势的竞技场。”这个视角把道德抛在一边，具有严重的潜在影响。而在所有领域里，气候领域的全球溢出效应是最显著的，该领域的合作也是最关键的。未能采取行动意味着穷国将深受其害。
This is the conclusion of a chapter on the economic impact of weather shocks, in the International Monetary Fund’s latest World Economic Outlook. The largest negative impacts of the shocks being made more frequent by global warming are on tropical countries. Nearly all low-income countries are tropical. Yet these countries are the least able to protect themselves. Thus they are innocent victims of changes for which they bear no responsibility.
这是国际货币基金组织(IMF)最新发布的《世界经济展望》(World Economic Outlook)中有关天气冲击的经济影响一章的结论。全球变暖引发了更高频度的冲击，受到最大负面影响的是热带国家。几乎所有低收入国家都在热带，这些国家的自我保护能力也是最低的，于是它们成了自身没有任何责任的变化的无辜受害者。
In assessing these risks, one has to start from the proposition that anthropogenic global warming is a reality. The intellectual industry devoted to denying this is well-funded and noisy. But its arguments are highly unconvincing. The underlying physics are undeniable. Furthermore, the empirical connection between rising concentrations of greenhouse gases and temperature is unambiguous. If little or no action is taken, average temperatures could rise by 4°C, or more, above pre-industrial levels by the end of the century. Aware of the lengthy lead times needed if effective action is to be taken, both to mitigate climate change and adapt to it (where inescapable), rational people would act now.
人们在评估这些风险时，必须从这样一个命题出发：人为全球变暖是一个事实。致力于否认这一点的知识产业不但资金充足，且声势浩大。但其论据极其缺乏说服力。人为全球变暖的物理机制是不可否认的。此外，温室气体浓度上升和气温上升之间存在明确的实证联系。若不采取或仅采取少量行动，到本世纪末平均气温可能会比工业化之前水平高出4摄氏度，甚至更多。深知即使采取有效行动后还需要漫长时间——无论是缓解气候变化还是(在气候变化不可避免的情况下)适应它——才能看到效果，理性的人现在就会采取行动。
The main obstacles to such action are three. First, specific economic interests, notably in the fossil fuel industry, are understandably opposed to action and, not infrequently, to the science that suggests it is necessary. Second, free-marketeers, who despise both governments and environmentalists, reject the science, because of its (to them) detestable policy implications. Third, few wish to inconvenience themselves, let alone threaten their standard of living, for the sake of the future, or people in poorer countries.
气候行动主要有三大障碍。首先，可想而知一些特定经济利益——尤其是化石燃料行业——是反对气候行动的，且往往反对提出气候行动有必要的科学。其次，既鄙视政府又鄙视环保人士的自由市场论者不接受科学家的结论，原因是其可憎的政策影响(对他们而言)。第三，没多少人愿意为了未来或贫穷国家的人民而给自己添麻烦，更不用说危及自己的生活水平。
So what is the evidence of the impact on the poorest of failure to act? The IMF authors start from our knowledge that higher temperatures make a range of weather-related disasters more likely because there will be more energy in the weather system. Such effects will include a greater frequency of — and greater damage done by — cyclones, floods, heatwaves and wildfires.
那么有什么证据能表明，不采取气候行动会对贫穷国家造成冲击呢?IMF的作者们从我们已经掌握的知识出发，即气温升高会增加一系列天气灾害的可能性，因为天气系统里将积蓄更多能量。后果将包括更高频度且破坏力更大的飓风、洪水、热浪和野火。
Furthermore, the increased frequency of extreme events will also do relatively more damage to the poorest countries. This is so for two reasons: these countries are located in the regions of the world most likely to be adversely affected; and they are least able to protect themselves against, or manage, the impact. For the median low-income developing country, with an average temperature of 25°C, the effect of a 1°C increase in temperature is to lower that year’s growth by 1.2 percentage points.
此外，极端天气灾害频发对贫穷国家的损害也相对较大。这缘于两个原因：这些国家位于全球最可能受到不利影响的地区;而且它们抵御或应对灾害冲击的能力也是最差的。对于典型的低收入发展中国家，若平均气温为25摄氏度，那么气温每升高1摄氏度就会导致当年经济增长下降1.2个百分点。
Moreover, the impact is long-lasting. These costs come from the adverse effects of heat on productivity, agricultural output, health and even conflict. Extreme heat is costly. Adaptation to extreme weather remains very hard for poor countries. We have witnessed this autumn the far more damaging impact of huge storms on poorer countries, such as those in the Caribbean, than on the much wealthier US.
而且天气灾害的影响是持久的。其代价来自高温对生产率、农业产出、健康甚至冲突的不利影响。极端高温的损害尤其大。贫穷国家仍然很难适应极端天气。今年秋天，我们见证了大风暴对较贫穷的国家——如加勒比地区国家——造成的破坏远远超过对富得多的美国的破坏。
It is possible for well-managed nations to reduce these adverse impacts. Countries with superior infrastructure, better-regulated capital markets, flexible exchange rates and more accountable and democratic institutions recover faster economically from the adverse impact of temperature shocks than others. Hot regions in high-income countries also cope better than those in poorer ones. All this supports the view that the poorest countries are likely to be the most damaged by rising temperatures. The populations of such countries are more vulnerable because they are closer to subsistence.
管理有方的国家是可以减少这些不利影响的。对于那些基础设施优越、资本市场规范、汇率有弹性且机构比较负责和民主的国家，其经济从气温冲击的不利影响中恢复过来的速度要快于其他国家。炎热地区高收入国家的应对能力也比穷国更好。这一切都支持一个观点：最贫穷的国家可能受到气温上升的最严重伤害。这些国家的百姓更脆弱，因为他们更接近贫困线。
With the temperature increases projected by 2100 under unmitigated climate change, annual real incomes per head of a representative low-income country would be 9 per cent lower than they would otherwise be. This would impose large costs on their vulnerable groups. Moreover, such a forecast ignores the risks and uncertainties around any such estimates. A planet 4°C warmer than the pre-industrial average would be so different from the one we are now used to that the implications are in significant part unknowable.
根据未受缓解的气候变化下到2100年的升温预测，典型低收入国家的人均实际收入将比原本应有水平低9%，这将给其弱势群体带来巨大损失。而且，该预测还没有考虑围绕此类估测的风险和不确定性。一个气温比工业化之前平均水平高出4摄氏度的地球，将与我们习以为常的地球如此不同，以至于有很大一部分影响是不可知的。
The IMF’s analysis has a number of serious implications. First and most important, low-income countries need to develop quickly to be better able to cope with weather shocks. Second, their development needs to be consistent with mitigating the rise in global temperatures. Third, we need rapid improvements in the relevant technologies and their swift dissemination. Fourth, we also need to help poor countries adapt to the changes in climate already sure to happen. Fifth, we need to develop insurance against weather-related shocks to poor countries. Finally, a moral case also exists for compensating losers from the costs of the unmitigated climate changes being imposed by richer countries.
IMF的分析有一些重要含意。首先最重要的是，低收入国家需要迅速发展，以更好地应对天气冲击。第二，它们的发展需要与缓解全球气温上升的目标一致。第三，我们需要快速改进相关科技，并加快它们的普及。第四，我们还需要帮助穷国适应已经肯定会发生的气候变化。第五，我们需要开发保险以保护穷国免受天气相关灾害冲击。最后还有一个道德方面的考量，要补偿那些因富国造成的未受缓解的气候变化而付出代价的输家。
We should not let the urgent stop us from thinking about the important. The linked challenges of climate and development will shape humanity’s future.
我们不应该让紧急的事阻止自己去思考重要的事。相互关联的气候与发展挑战将塑造人类的未来。
