文章主题分析：Global Warming
Smoke is clouding our view of global warming, protecting the planet from perhaps three- quarters of the greenhouse(温室)effect．
cloud v.使不清晰, 使多云，使阴暗;
The sky clouded over.天空中云层密布(clear up v. 放晴)
in the clouds 空想的; 想象的；不真实的；不切实际的
被选择项分析：
A Atmospheric Scientists
B The Calculations Made at the Berlin Workshop
C The Previous Calculations of the Effect of Aerosols
D The Scientists’Agreement
E The Authoritative Conclusion
F Greenhouse Gases
分析：B和C中一定会有答案出现。
E．分析：该段结构“这是一个具有很大影响的一个结论，在。。地方达成的，由。。科学家达成”（注意借助各句子主干内容判断句子大意），所以判断E（段落中提到的科学家仅仅是为了给提到的结论增加权威性）是答案。同时可以判断A是干扰项可以被排除掉。
（A Atmospheric Scientists）
B The Calculations Made at the Berlin Workshop
C The Previous Calculations of the Effect of Aerosols
D The Scientists’Agreement
F Greenhouse Gases
24 Paragraph 3
3 IPCC scientists have suspected for a decade that aerosols(浮质)of smoke and other particles from burning rainforest，crop waste and fossil fuels are blocking sunlight and counteracting the warming effect of carbon dioxide(二氧化物)emissions．Until now，they reckoned that aerosols reduced greenhouse warming by perhaps a quarter, cutting increases by 0．2。C．So the 0．6。C of warming over the past century would have been 0．8。C without aerosols．
C：分析：根据段落中出现的核心词aerosols首先判断C很可能是答案，而且段落倒数第2句的大意“Until now，they reckoned that…/在此以前，他们一直估计…”，该结构含义与C呼应。
（A Atmospheric Scientists）
B The Calculations Made at the Berlin Workshop
D The Scientists’Agreement
F Greenhouse Gases
25 Paragraph 4
4 But the Berlin workshop concluded that the real figure is even higher--aerosols may have reduced global warming by as much as three—quarters，cutting increases by 1．8。C．If so，the good news is that aerosols have prevented the world getting almost two degrees warmer than it is now．But the bad news is that the climate system is much more sensitive to greenhouse gases than previously guessed．
B．分析：段首句中出现了Berlin workshop，比较剩下的被选项（对应被选项中的核心词：D: agreement; F: greenhouse gases）判断B最合适。
