科研人员发现，在1998年到2008年期间，大气二氧化碳浓度稳步增加，同时地球温度下降，这符合自然和人类因素造成的气候变化。Robert Kaufman及其同事使用模型模拟从而确定可能引发了长达10年的变冷事件的因素，如果没有这些因素，这将是变暖的10年，论文作者说，研究的时间段是一个正常的太阳能量输出衰减的11年周期的一部分。这10年也包括了从厄尔尼诺到拉尼娜（常常导致变冷的一种海洋-大气现象）气候模式的周期变化。论文作者进一步指出，中国在2003到2007年间的煤消耗量加倍，导致了硫排放剧增，这可能对地球具有致冷作用。科研人员提出，这种致冷效应可能抵消了由于二氧化碳浓度增加而导致的正在进行的变暖，让自然界的力量支配着地球的温度。这组作者说，他们提出的这种解释可能预示着未来一个迅速的全球变暖的时期，这是由于太阳输入增加，而且由于中国为烧煤的锅炉安装了消除气溶胶的装置。
全球变暖的调节开关得到解释
生物探索推荐英文摘要
Dimmer switch on global warming explained
The atmospheric concentration of carbon dioxide increased steadily between 1998 and 2008 even as the Earth's temperature declined, consistent with climate change resulting from both natural and human causes, researchers find. Robert Kaufman and colleagues used model simulations to pinpoint factors that may have triggered a decade-long cooling event during what was otherwise a period of warming. The study period was part of a normal 11-year cycle of declining solar energy input, according to the authors. The decade also included a cyclical shift from an El Niño pattern to a La Niña climate pattern-an ocean-atmosphere phenomenon that frequently causes cooling. The authors further noted that China doubled its coal consumption from the years 2003 to 2007, leading to a huge increase in sulfur emissions that may have had a cooling effect on the planet. The researchers suggest that this cooling effect may have counteracted ongoing warming due to increased carbon dioxide concentrations, permitting natural forces to predominate the planet's temperature. The proposed explanation may portend a future period of rapid global warming as solar input rises and as China installs scrubbers that remove aerosols from coal-fired boilers, according to the authors.
