摘要
An irreducibly simple climate-sensitivity model is designed to empower even non-specialists to research the question how much global warming we may cause. In 1990, the First Assessment Report of the Inter- governmental Panel on Climate Change （IPCC） expressed ＂substantial confidence＂ that near-term global warming would occur twice as fast as subsequent observation. Given rising CO2 concentration, few models predicted no wann- ing since 2001. Between the pre-final and published drafts of the Fifth Assessment Report, IPCC cut its near-term warming projection substantially, substituting ＂expert assessment＂ for models＇ near-term predictions. Yet its long-range predictions remain unaltered. The model indi- cates that IPCC＇s reduction of the feedback sum from 1.9 to 1.5 W m^-2 K^-1 mandates a reduction from 3.2 to 2.2 K in its central climate-sensitivity estimate; that, since feed- backs are likely to be net-negative, a better estimate is 1.0 K; that there is no unrealized global warming in the pipeline; that global warming this century will be 〈1 K;and that combustion of all recoverable fossil fuels will cause 〈2.2 K global warming to equilibrium. Resolving the discrepancies between the methodology adopted by IPCC in its Fourth and Fifth Assessment Reports that are highlighted in the present paper is vital. Once those dis- crepancies are taken into account, the impact of anthro- pogenic global warming over the next century, and even as far as equilibrium many millennia hence, may be no more than one-third to one-half of IPCC＇s current projections.
一个 irreducibly 简单的气候敏感模型被设计授权甚至非专家研究多少的问题全球温暖我们可以引起。在 1990，气候变化(IPCC ) 上的 Intergovernmental 面板的第一份评价报告表示了近期的全球温暖将象随后的观察一样快发生两次的实质的信心。给定的升起的公司 < 潜水艇 class= “ a-plus-plus ” > 2 </sub> 集中，很少模型没预言自从 2001，温暖。在期末考试前和第五份评价报告的出版草稿之间， IPCC 实质地切了它的近期的温暖设计，用专家评价代替模型近期的预言。然而，它的远程的预言仍然保持未改变。模型从 1.9 ～ 1.5 显示反馈和的那 IPCC 减小 ? W ? m < 啜 class= “ a-plus-plus ” > 2 </sup>?K<sup class= “ a-plus-plus ” > 1 </sup> 从 3.2 ～ 2.2 要求减小 ? 在它的中央气候敏感估计的 K；自从反馈是可能的网否定，更好的估计是 1.0 ? K；在管道有不没有实现的全球温暖；那全球温暖这个世纪将是 < 1 ? K；并且所有可重获的石块的那燃烧造成愿望原因 < 2.2 ? K 全球温暖到平衡。解决在 IPCC 在它的第四和第五个评价采用的方法论之间的差异报导那在现在的论文被加亮是重要的。一旦那些差异被考虑，在下一个世纪的人为的全球温暖的影响，并且因此远及平衡弄平许多几千年，可以是仅仅三分之一个到 IPCC 当前的设计的一个一半。
