Global warming is the most serious problem humanity has ever faced, There’s more hype (宣传) on this (26) than any other. In the late 1970s computer models predicted that because of the heat-trapping buildup of carbon dioxide in the (27) , the earth would warm up by several degrees over the next century. A lot of bad weather gets linked to global warming: in the media, which regularly predict that more and (28) hurricanes, longer (29) and more (30) rainstorms will result. What has actually been going on One computer model says the earth’s temperature should have already increased by an easily (31) 0.3 to 0.4 degrees Celsius since 1979. Some (32) , however, show that the earth’s temperature has actually cooled slightly over the last 18 years. And despite (33) , the frequency of intense Atlantic hurricanes and their (34) have not increased over the past half-century. If climate models turn out to be correct, it may be prudent to limit carbon-dioxide (35) in the future. But many experts feel there is no need to rush into extreme action.