[填空题]

All big ideas start life on the fringes of debate. Very often it takes a shocking event to move them into the mainstream. Unti1 last year climate change was mainly the interest of scientists and green lobbyists. But since Hurricane Katrina, something seems to have changed, particularly in America. Nobody knows whether the hurricane really had anything to do with the earth warming. But for the first time less green voters and big business had a clearer idea about the "extreme weather events" whose increasing frequency scientists had been talking about.
There are plenty of anecdotal signs of change: Britain’s pro-business Conservatives have turned green; A1 Gore is back in fashion in America; hybrid cars no longer get stared at. (41)______.
So far the political rows about global warming have centred on two polluters, smoggy factories and dirty cars. (42)______.
In some ways, the airlines are an odd target for greens. They produce only around