For the last fifty years, the globe has been warming up. It is true that the average temperaturer 1is only about two degrees, but that has beene 2to start the glaciers 3(recede)in many parts of the world. A rise of one degree per generation is a largein 4. Nature seldom moves as swiftly as this. We may have been helping her. To a very large 5, the temperature of the Earth is determined 6the amount of solar heat which the atmosphere can keep. The air above us sets like the glass in a greenhouse, trapping many of the heat waves which wouldother 7bounce back into space. Carbon dioxide in the air is mostly responsible 8the "greenhouse effect" : it is a gas produced by all our countless fires, furnaces(熔炉)and internal combustion engines(内燃机). The end of the age of fossil fuels is already in sight: soon in one or two centuries at the roost we will have wasted all the world'sre 9of oil and coal. This no longer means disaster, for 10(atom)energy has arrived in time to save our civilization from dying through lack of power.