23 de novembro de 2009

E continua ...

 

As figuras acima foram retiradas do artigo de James Hansen, referenciado por último (muito bom - pelo menos esse deviam ler).
  • Tipping Points: Melting Ice, Rising Oceans | SolveClimate.com: "Global warming is a time bomb. There may still be time to defuse it, but that requires policy-makers to take the actions that are needed, not the ineffectual actions they are discussing. Despite the publicity that global warming has received, there is a large gap between what is understood by the relevant scientific community, and what is known by the people who need to know, the public and policymakers. Global warming is small compared to day-to-day weather fluctuations, so it is hard for people to recognize that we have a crisis – but we do. The climate system has great inertia, caused, e.g., by the 4-kilometer-deep ocean and the thick ice sheets on Antarctica and Greenland, which have only partly responded to the human-made changes of atmospheric composition. That inertia is not our friend. It is a Trojan horse. By the time the public notices that change is underway the momentum of the climate system may be sufficient to guarantee much larger changes. The climate system can pass tipping points, such that large change continues out of our control. The bad news is that we have already passed into a dangerous range of atmospheric carbon dioxide. The good news is that if we act smart and promptly it is still feasible to achieve a safe level of atmospheric gases, and the actions needed to achieve that would have multiple benefits in addition to climate stability. There are several climate tipping points of special concern.[...]"

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