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Global Climate Change, a change which is attributed directly or indirectly to human activities that alter the global atmospheric composition, added to natural climate variability observed in comparable periods of time (ERA, 1997).
The IPCC (International Panel on Climate Change), 2500 a panel of top scientists, agreed that "a discernible human influence on global climate and can be detected among the many variables of the natural environment." According to the panel, the temperature of the earth's surface has risen approximately 0.6 ° C over the last century. Emissions of carbon dioxide by burning fuel, have risen to 6.25 billion tons in 1996, a new record. Moreover, 1996 was one of the five hottest years on record there (since 1866). Furthermore it is estimated that the damage related to climate disasters reached 60 billion U.S. $ in 1996, another new record (GCCIP). |
According to the International Panel on Climate Change, a doubling of greenhouse gases increase the temperature between 1 and 3.5 ° C. While not seem much, it is equivalent to return to the last glaciation, but in the reverse direction. On the other hand, the temperature rise would be the fastest in the last 100,000 years, making it very difficult for the world's ecosystems to adapt.
The principal change to date has been in the air, We have changed and continue changing the balance of gases that make up the atmosphere. This is particularly evident in key greenhouse gases such as CO2, methane (CH4) and nitrous oxide (N2O). These natural gases are less than one tenth of 1% of atmospheric gases, but are vital acting as a "blanket" around Earth. Without this layer the global temperature would be 30 ° C lower.
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