听力题 W: Everyone seems to be talking about climate change these days! M: I''m not surprised. It''s all these greenhouse gases—that''s what''s causing the problem! W: What are the greenhouse gases? M: You know, carbon dioxide, which comes mainly from the burning of fossil fuels, such as oil, gas and coal. W: I''ve never understood why that''s a problem. M: Evidently these gases build up in the earth''s atmosphere, and trap the heat from the sun. W: And so this heat is warming the planet? M: Exactly! W: Well, isn''t that good news? I hate these cold winters we get! M: Yes. But what''s good for you here may not be so good for people elsewhere in the world. For the average world temperatures could rise. That can have a huge effect on local climates and ecosystems around the world. W: So you really think that these floods we''ve seen in the news could be caused by global warming? M: Sure! And also the droughts and the storms. W: So what can we do about it? M: It''s not realistic to stop using fossil fuels today. But we can start trying to reduce carbon dioxide emissions. W: And look for alternative sources of energy too, of course!