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  The dangers of a population explosion have been all over the newspapers lately and indeed the world population could reach seven billion in just two years and eight billion perhaps in the next two decades. But that’s not the only story. Dramatic declines in fertility rates in some countries and high rates in others pose a critical challenge. One must be reminded that the growth of world population—which now stands at an estimated 6. 8 billion human inhabitants—has greatly impacted all life forms and the overall natural environment of the planet.
    Although the population of the world continues to grow substantially—79 million per year—the rate of growth has declined by nearly half over the last 40 years—from 2 percent to 1.2 percent a year. The cause for the slowdown is declining fertility rates. However, while the average global fertility has dropped from about 5 to 2.6 births per woman during the past 50 years, considerable uncertainty exists about the future. Insofar as fertility is the engine driving the future size of world population, this uncertainty about the path of fertility, in the coming years is one of the central and challenging questions of this century.
 

【参考答案】

最近，人口激增问题频频出现在报纸上。事实上，世界人口可能会在接下来两年里达到七十亿并且可能在接下来二十年内突破八十亿。但......

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We, the Finance Ministers and Central Bank Governors of the G-20, have a common goal of promoting employment, welfare and development in our countries. We are convinced that strong and sustained economic growth is necessary both at national and global level to achieve this end. We have therefore discussed the requirements for long-growth on the basis of our own experience and believe that domestic policy needs to address three tasks: establishing and maintaining monetary and financial stability; enhancing domestic and international competition; and empowering people to participate. Transparency and accountability within an internationally agreed framework of codes and standards remain key to ensuring sustained economic growth and stability at the global level. We agreed on the following key elements that will guide our domestic economic policies in the future. In implementing these elements, microeconomic aspects must be given due consideration. As these principles are interlinked, they must be implemented consistently, with due regard to possible trade-offs and complementarities, because many single elements have the potential of blocking the positive effects of others. While appropriate and credible policies are the basis for economic growth, they need to be backed by high-quality institutions, including ethical standards in corporate governance. Policymakers should build institutions in parallel with engaging in reforms and also ensure that institutions stay consistent with the requirements of a changing environment. However, given the diversity of institutional settings and the success of different economic strategies among G-20 countries, there is no single template for strong long-term growth. Policies need to be shaped to the special circumstances in individual countries. ……
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It is said that the Inuit have many words for snow, but when it comes to the Northwest Passage only one type of frozen water matters: multiyear ice. It can slice through the hull of a ship like a knife through butter and it persists in the passage’s waters despite unprecedented warming in the Arctic Ocean, thwarting shippers in search of a shortcut between Europe and Asia. The fabled Northwest Passage has made headlines ever since it thawed last year for the first time. For three centuries the quest for an expedited route between the Atlantic and Pacific oceans rivaled today’s space race, with European superpowers vying for the prize. Hundreds of sailors and countless expeditions ventured into Canada’s Arctic waters, including such naval luminaries as Sir Francis Drake, Captain James Cook and the ill-fated Henry Hudson, who left his name—and lost his life—on the Canadian bay that marks its entrance. Now, with the Arctic’s sea ice shrinking at a rate of 10 percent per decade, this coveted shipping lane has opened for business—but shippers are not rushing to use it. The reason: as fate would have it, global warming appears to also be increasing the amount of potentially deadly multiyear ice chunks lurking in the newly opened pathway. The thing is, the Canadian Arctic has a totally different ice regime than the Arctic Ocean, says Stephen Howell, a climatologist at the Interdisciplinary Center on Climate Change at the University of Waterloo in Ontario. In fact, the Canadian Arctic Archipelago acts as a drain trap for ship-wrecking multiyear ice, Howell says. This year, for example, when the first-year ice in the passage had melted, it opened the way for multiyear ice (MYI) from the Queen Elizabeth Islands to flow into and clog the Northwest Passage. We call it a ’MYI invasion’ and that’s going to be the threat as we transition to an ice-free summertime Arctic, he says. The first-year ice, that’s sort of like Swiss cheese and you can just plow through it, Howell says. This ice freezes over a winter and is seldom thicker than three feet (one meter). Often, first-year ice melts the summer after it’s frozen, but if it doesn’t, it becomes thicker the following winter and becomes multiyear ice. The multiyear ice isn’t like Swiss cheese; it’s solid and trouble for ships that collide with it, he says.
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