"Nobody really knows" was Donald Trump’s assessment of man-made global warming, in an interview on December 11th. 【F1】 As far as

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问题     "Nobody really knows" was Donald Trump’s assessment of man-made global warming, in an interview on December 11th. 【F1】 As far as the atmosphere is concerned, that puts him at odds with most scientists who have studied the matter. They do know that the atmosphere is warming, and they also know by how much. But turn to the sea and Mr. Trump has a point. Though the oceans are warming too, climatologists readily admit that they have only a rough idea how much heat is going into them, and how much is already there.
    Many suspect that the heat capacity of seawater explains the climate pause of recent years, in which the rate of atmospheric warning has slowed. 【F2】 But without decent data, it is hard to be sure to what extent the oceans are acting as a heat sink that damps the temperature rise humanity is visiting upon the planet—and, equally important, how long they can keep that up.
    This state of affairs will change, though, if a project described by Robert Tyler and Terence Sabaka to a meeting of the American Geophysical Union, held in San Francisco this week, is successful. Dr Tyler and Dr Sabaka, who work at the Goddard Space Flight Centre, observe that satellites can detect small changes in Earth’s magnetic field induced by the movement of water. They also observe that the magnitude of such changes depends on the water’s temperature all the way down to the ocean floor. That, they think, opens a window into the oceans which has, until now, been lacking. To measure things in the deep sea almost always requires placing instruments there. 【F3】 The supply of oceanographic research vessels, though, is limited, and even the addition in recent years of several thousand "Argo" probes (floating robots that roam the oceans and are capable of diving to a depth of 2,000 metres) still leaves ocean temperatures severely under-sampled.
    Satellites, however, can look at the whole ocean—and, if they are properly equipped, can plot ways in which Earth’s magnetic field is deflected by seawater. This deflection happens because seawater is both electrically conductive and always on the move. Crucially, saltwater’s conductivity increases with its temperature. This means the deflection increases, too. 【F4】 And since the magnetic field originates from within Earth, it penetrates the whole ocean, from bottom to top. So any heat contributes to the deflection.
    【F5】 All this means that, if you know where and how ocean water is displaced, the changes in the magnetic field, as seen from a satellite, will tell you the heat content of that water. Dr Tyler and Dr Sabaka therefore built a computer model which tried this approach on one reasonably well-understood form of oceanic displacement, the twice-daily tidal movement caused by the gravitational attraction of the moon.
【F3】

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答案但是,能为海洋学研究提供的舰船总是有限的。即使最近几年,科学家拥有了几千只“Argo"探测器(可漂浮在海洋表面并能深潜2 000米的机器人),海洋温度研究的样本信息仍然严重不足。

解析 该句为and引导的并列句。第一个并列句的主语为The supply of oceanographic research vessels,is为系动词,表语为limited;第二个并列句的主语为the addition of several thousand“Argo”probes,谓语为leaves,宾语为ocean temperatures,宾语补足语为under-sampled。其中括号内容为同位语,对“Argo”probes作补充说明。同位语是解释说明名词或代词的,在句中起修饰、限定或说明的作用,可以去掉,但是句子意思上会有语义的残缺。但是插入语就不同,去掉之后完全不影响句子的意思,没有任何影响。
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