问题 选择题

 由于大气的散射作用,人们把黄昏的余晖与黎明的曙光相接的现象叫“白夜”,白夜线是指白夜现象发生的最低纬度。图5中弧线BAC为晨昏线。当北半球发生白夜现象范围最大时,读图回答下题。

小题1:图示时刻,下列各地理现象最有可能发生的是(    )

A.在法国南部的海滩“沐浴”午后阳光

B.在几内亚湾上的游轮欣赏落日余晖

C.在西湖感受“二月春风似剪刀”

D.在鄱阳湖观“落霞与孤鹜齐飞”小题2:图示时刻,下列有关图中各地点的叙述正确的是(    )

A.此时太阳位于A点正南方位

B.漠河还没开始出现白夜现象

C.D点比漠河先迎接日出

D.阿勒泰地区太阳高度角接近一天中最大值小题3:若黄赤交角变大到25°,白夜线最低纬度将(    )

A.南移

B.北移

C.不变

D.都有可能

答案

小题1:B

小题2:C

小题3:A

小题1:当北半球发生白夜现象范围最大时,北极圈及其以北地区出现极昼现象,为北半球的夏至日,则图中100°E地方时为0:00。法国南部处于夜晚;几内亚湾处于傍晚时分;鄱阳湖为深夜。所以本题选择B选项。

小题2:A点此时地方时为0:00,太阳位于地平线的正北方;漠河处于白夜现象的范围内;D点位于晨线附近,较早日出;阿勒泰位于深夜。所以本题选择C选项。

小题3:若黄赤交角变大到25°,则极昼的范围扩大到65°N,白夜的范围将扩大,则白夜线最低纬度将向南移动。所以本题选择A选项。

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Feb.20, 2011
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