温室效应
参考答案：
存在于大气中的某些痕量物质和存在于对流层中的臭氧具有吸收太阳能在近地表面的长波辐射从而使大气增温的作用。
The cost of living in Glasgow is among the lowest in Britain,________ the quality of life is probably one of the highest. [ ]
A. since
B. when
C. as
D. while
光轴
