When the atmospheric concertrations of these gases increase, however, more heat is trapped and the Earth's emperature rises. Over the last 100 years, the global average temperature has increased by 1°F and many experts insist that this global warming is mostly due to human activities. As a result of increased industry, agriculture, transportation, deforestation and the burning of fuels, nearly 6 tonnes of carbon dioxide is released into the atmosphere annually or every one of the Earth's 6 billion people today. The atmospheric concentration of carbon dioxide has risen by more than 30% in the last 250 years with half of this increase occurring since 1960. Given this date,it seems that the link between human activities nad rising global temperatures cannot be denied. A temperature increase of 1°F sounds insignificant, but if we continue toproduce greenhouse gases in such huge quantities, we should expect severe consepuences. Recent repots from the Intergovernmental Panel on Climate Change(IPCC) warned that golbal warming will cause dramatic climate changes including more frequent floods, heat waves,and droughts.
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