科學家怎麼知道氣候變暖沒有錯呢？

[馬丁]

Good article on Fox news site includes:

引用：

… since nothing in science can ever be proven with 100 percent certainty, how is it that scientists can be so sure that we are the cause of global warming? For years, there has been clear scientific consensus that Earth’s climate is heating up and that humans are the culprits behind the trend, says Naomi Oreskes, a historian of science at the University of California, San Diego. A few years ago, she evaluated 928 scientific papers that dealt with global climate change and found that none disagreed about human-generated global warming. The results of her analysis were published in a 2004 essay in the journal Science. And the Intergovernmental Panel on Climate Change (IPCC), the National Academy of Sciences and numerous other noted scientific organizations have issued statements that unequivocally endorse the idea of global warming and attribute it to human activities. …

The effects of putting massive amounts of carbon dioxide in the air were first predicted in 1896 by Swedish chemist Svante Arrhenius. Noted oceanographer Roger Revelle’s 1957 predictions that carbon dioxide would build up in the atmosphere and cause noticeable changes by the year 2000 have been borne out by numerous studies, as has Princeton climatologist Suki Manabe’s 1980 prediction that the Earth’s poles would be first to see the effects of global warming. In 1988, NASA climatologist James Hansen outlined three scenarios of how the global average temperature might rise over the next 30 years. Nearly 20 years later, the observed rise has followed his medium-range scenario with high accuracy. Hansen’s model predictions are "a shining example of a successful prediction in climate science," said climatologist Michael Mann of Pennsylvania State University.

… Schmidt says that predictions by those who doubted global warming have failed to come true. "Why don’t you trust a psychic? Because their predictions are wrong," he told LiveScience. "The credibility goes to the side that gets these predictions right." Mounting evidence Besides their successful predictions, climate scientists have been assembling a "body of evidence that has been growing significantly with each year," Mann said. Data from tree rings, ice cores and coral reefs taken with instrumental observations of air and ocean temperatures, sea ice melt and greenhouse gas concentrations have all emerged in support of climate change theory. "There are 20 different lines of evidence that the planet is warming," and the same goes for evidence that greenhouse gases are increasing in the atmosphere, Schmidt said. "All of these things are very incontrovertible." …

One argument commonly used to cast doubt on the idea of global warming is the supposed predictions of an impending ice age by scientists in the 1970s. One might say: First the Earth was supposed to be getting colder; now scientists say it’s getting hotter — how can we trust scientists if they’re predictions are so wishy-washy? Because the first prediction was never actually made. Rather, it’s something of an urban climate myth. …

Global Warming: How Do Scientists Know They’re Not Wrong?

[作者]

文章