DIRECTIONS for Questions: Four alternative summaries are given below each text. Choose the option that best captures the essence of the text.
Although almost all climate scientists agree that the Earth is gradually warming, they have long been of two minds about the process of rapid climate shifts within larger periods of change. Some have speculated that the process works like a giant oven or freezer, warming or cooling the whole planet at the same time. Others think that shifts occur on opposing schedules in the Northern and Southern Hemispheres, like exaggerated seasons. Recent research in Germany examining climate patterns in the Southern Hemisphere at the end of the last Ice Age strengthens the idea that warming and cooling occurs at alternate times in the two Hemispheres. A more definitive answer to this debate will allow scientists to better predict when and how quickly the next climate shiftwill happen.