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During the past 1,000 years, the climates of the British Isles and continental Europe have undergone various episodes of change. It has long been believed that the demographic and economic expansion of Europe between the tenth and thirteenth centuries coincided with, and was perhaps encouraged by, a period of relative warmth, favorable to the expansion of cereal cultivation and the colonization of previously inhospitable environments. This benign phase, although variously dated, was seen to lie between a period of less favorable conditions in the late and post-Roman centuries and the so-called Little Ice Age of the early modem period, which was characterized by an overall cooling of the climate and, in particular by an increased severity of winters. Climatic deterioration was seen to have begun by circa 1300, presaged by an increase in stormy conditions in Europe, and associated with runs of wet and cool summers and the widespread harvest failures and livestock mortality of the years 1315-1322.
The integrity of the so-called medieval warm period, once considered a global phenomenon, has, however, been called into question by recent paleoenvironmental research. The picture that now emerges is of a less coherent and perhaps more geographically restricted phase—variously dated —of relative warmth, when temperatures in northwest Europe and the North Atlantic area were on average higher than in the post-Roman and early modern periods, although probably not warmer than in the late twentieth century. Some types of evidence, including the records of the advance and retreat of Alpine glaciers, suggest that the later fourteenth and early fififteenth centuries may have seen a notable climatic downturn, followed by a temporary amelioration around1500, before renewed cooling into the Late Maunder Minimum period of 1675-1715. The relationship between glacial advance or retreat and temperature is, however, complex. A study of winter severity in central Europe during the fourteenth century found no clear trend, rather the alternation of runs of cold and mild winters.with the most sustained period of severe winters falling in the period 301-1328. English documentary sources have been used to suggest a cooling trend from circa 1240-1340, with a subsequent amelioration followed by renewed cooling from circa 1510, but the sporadic nature of this data series necessitates caution. A long-term cooling trend in the northern hemisphere between the twelfth/thirteenth and the seventeenth centuries does, however emerge from a plethora of sources, including tree-ring data, the study of lake and ocean sediments, and analysis of Greenland ice cores.
[阅读&逻辑 ]冲分救命题 -9340
The highlighted sentence serves primarily to
[阅读&逻辑 ]冲分救命题 -9339
The author would most likely agree with which of the following assertions about the environmental impact of hydroelectric power plants?
[阅读&逻辑 ]冲分救命题 -9338
The passage suggests that which of the following contributed to the erosion after the First World War of the progress previously realized by the labor movement in the United States?
[阅读&逻辑 ]冲分救命题 -9337
According to the passage, which of the following statements about the National War Labor Board is true?
[阅读&逻辑 ]冲分救命题 -9336
It can be inferred from the passage that which of the following was one of Local 36’s grievances against the Little Rock laundry owners?
[阅读&逻辑 ]冲分救命题 -9335
The passage is primarily concerned with discussing
[阅读&逻辑 ]冲分救命题 -9334
According to the passage, Appalachian square dancing differs from English country dancing in that Appalachian square dancing
[阅读&逻辑 ]冲分救命题 -9333
The passage suggests that which of the following was true of
[阅读&逻辑 ]冲分救命题 -9332
The statements given are structured to lead to which of the following conclusions?
[阅读&逻辑 ]冲分救命题 -9331
Consider each of the choices separately and select all that apply. It can be inferred that historical demographers generally believe which of the following about communities of fewer than 10,000 people in early-modern Germany?
[阅读&逻辑 ]冲分救命题 -9330
The author suggests that according to historical demographers, the birth rate in early-modem German cities
[阅读&逻辑 ]冲分救命题 -9329
Which of the following most logically completes the argument?
[阅读&逻辑 ]冲分救命题 -9328
The highlighted portion of the passage serves primarily to
[阅读&逻辑 ]冲分救命题 -9327
According to the passage, certain African literatures have
[阅读&逻辑 ]冲分救命题 -9326
It can be inferred from the passage that the Tea Cess Committee reorganized as the Indian Tea Market Expansion Board in order to
[阅读&逻辑 ]冲分救命题 -9325
The passage suggests that "small packets of leaf fragments" were
[阅读&逻辑 ]冲分救命题 -9324
In the argument in the editorial, the part that is highlighted plays which of the following roles?
[阅读&逻辑 ]冲分救命题 -9323
Consider each of the choices separately and select all that apply.Which of the following can be inferred from the passage about the"period of relative warmth"
[阅读&逻辑 ]冲分救命题 -9322
Which of the following best describes the organization of the passage?
[阅读&逻辑 ]冲分救命题 -9321
It can be inferred that the author would agree with which of the following statements about glaciers?