美國研究人員發現，人類活動正在改變大氣含水量，研究人員說：「這是驗證人類活動（fingerprint）影響大氣中水蒸氣含量的第一個研究」。
該研究由加州「勞倫斯利佛摩爾氣候模式推演與交互比較國家實驗計畫（Lawrence Livermore National Laboratory's Program for Climate Modeling and Intercomparison）」進行，並刊登在9月17日美國國家科學院學報（Proceedings of the National Academy of Sciences）電子版上。
研究團隊成員之一的聖特（Benjamin Santer）指出：「當你加熱這個星球，你會增加大氣蘊含水氣的能力。而我們大氣層的水蒸氣含量從1988年開始每10年約增加每立方公尺0.41公斤的水氣，這種水氣變化是自然變化所無法解釋的，而由人為產生溫室氣體所造成的是最可能的解釋」。
聖特解釋，當自己本身就是溫室氣體的水蒸氣增加時，它會以正向回饋（positive feedback）循環的方式，擴大新增的大氣二氧化碳含量的增溫效應。
當大氣溫度因為人為增加二氧化碳、甲烷、一氧化氮、氯氟碳化合物而增加時，水蒸氣也隨之增加，並在大氣中留住更多熱氣，不斷循環的結果，導致水蒸氣的持續增加。
"This is the first identification of a human fingerprint on the amount of water vapor in the atmosphere," says Benjamin Santer, describing the findings of his study on the effect that humans are having on the atmosphere's total moisture content.
The study appears in the September 17 online edition of the "Proceedings of the National Academy of Sciences."
"When you heat the planet, you increase the ability of the atmosphere to hold moisture," said Santer, from Lawrence Livermore National Laboratory's Program for Climate Modeling and Intercomparison.
"The atmosphere's water vapor content has increased by about 0.41 kilograms per cubic meter per decade since 1988, and natural variability in climate just can't explain this moisture change," he said
"The most plausible explanation is that it's due to the human-caused increase in greenhouse gases."
More water vapor - which is itself a greenhouse gas - amplifies the warming effect of increased atmospheric levels of carbon dioxide in a cycle of positive feedback, Santer explained.
As the atmosphere warms due to human-caused increases in carbon dioxide, methane, nitrous oxide, and chlorofluorocarbons, water vapor increases, trapping more heat in the atmosphere, which in turn causes a further increase in water vapor.
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In my healing journey and learning to attain the breath awareness, I become aware of the reality that all the creatures of the world are breathing the same breath. Take action, here and now. From my physical being to the every corner of this out of balance's planet.
