But the strength of the greenhouse effect depends on the chemical composition of the atmosphere, because the phenomenon is due to the absorption of infra-red radiation by various gases in the air.

ECONOMIST: Climate change: Getting real | The

Weather is caused by disturbances within the atmosphere, but climate is controlled by external influences, such as the distribution of oceans and continents, the extent of ice and snow-cover, variations in the amount of energy from the sun, and changes in the chemical composition of the atmosphere.

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