New research suggests average global temperatures were higher in the past decade than over most of the previous 11,300 years, a finding that offers a long-term context for assessing modern-day climate change.

　　最新的研究显示，过去10年全球平均气温要高于此前11,300年的大部分时间，该结果为评估当今的气候变化提供了一个长期的参照。

　　The study, published Thursday in the journal Science, aims to give a global overview of Earth's temperatures over the past 11,300 years─a relatively balmy period known as the Holocene that began after the last major ice age ended and encompasses all of recorded human civilization.

　　周四发表在《科学》(Science)杂志上的这份研究报告旨在对过去11,300年的地球温度进行评估。过去的11,3000年是一段气候相对温暖的时期，被称为“全新世”。“全新世”从上个主要的冰河时期结束之后开始，所有有记录的人类文明都发生在这个阶段。

　　The research shows that a one-degree temperature variation that took 11 millennia to occur since the end of the last major ice age has been replicated in the 150 years since the early days of the Industrial Revolution.

　　研究显示，上一次主要的冰河时期结束之后，地球的平均气温在11,000年的时间里仅发生了一度的变化，但在工业革命初期之后，同样的变化仅用了150年。

　　Within that framework, the decade 2000-2009 was one of the warmest since modern record-keeping began, but global mean temperatures didn't breach the levels of the early Holocene. Now they are on track to do so, according to the Science paper. If the scientists' forecasts are correct, the planet will be warmer in 2100 than it has been for 11,300 years.

　　在这一框架下，2000年到2009年的10年是现代记录开始之后地球温度最高的十年之一，不过全球平均气温没有突破全新世初期的水平。但是根据《科学》上的这篇文章，如今，全新世早期的气温水平即将被打破。如果科学家的预测是正确的，2100年以后，地球将会比11,300年来的任何时期都更加温暖。

　　The study, conducted by researchers from Oregon State University and Harvard University and funded by the U.S. National Science Foundation, also looks to shed light on a crucial question: Is the spike in global temperature recorded in the past 150 years unusual─the result of greenhouse-gas emissions from human activity─or can it be explained as part of natural, long-term variations in temperature?

　　上述研究由俄勒冈州立大学(Oregon State University)和哈佛大学(Harvard University)的研究人员进行，由美国国家科学基金会(National Science Foundation)出资完成。该研究还试图解释一个关键的问题：过去150年发生的全球变暖，是人类活动产生的温室气体排放引发的非正常变化，还是地球温度长期自然变化的一部分？

　　The study points to human activity as the cause, because the suddenness of the shift in temperature appears to be out of whack with long-term trends.

　　研究指出，是人类活动造成的，因为气温的突然变化并不符合长期的趋势。

　　'What's different is the rate of change,' said Shaun Marcott, a paleoclimatologist at Oregon State and lead author of the paper. 'What we've seen over the past 150 years is much greater than anything we saw in the past 11,000 years.'

　　俄勒冈州立大学的古气候学家马科特(Shaun Marcott)说，关键在于变化的幅度。过去150年的变化比过去11,000年的任何变化都更加剧烈。

　　The task of estimating Earth's ancient climate, a discipline known as paleoclimatology, is a challenging one. It relies on proxy measurements taken from things such as marine fossils or ice cores that offer a physical record of past temperature. For example, as part of the process, scientists grow the marine organisms under varying temperatures, and link changes in their shells' chemical signature to different water temperatures. That data can then be used to study marine fossils. To confirm a finding, researchers typically check to see whether temperature records derived from one source match those derived from other, unrelated sources, such as ice cores.

　　古气候学是研究地球远古时代气候的学科，其难度很大。古气候学的研究依赖对海洋化石和冰芯等标本的模型测量。这些标本提供了远古气温的物理记录。例如，测量过程中，科学家们会在不同的温度下培养海洋有机生物，并找到它们贝壳的化学特征变化与水温的联系。这些数据接着将被用于海洋化石的研究。为了证实一项发现，研究人员一般需要检验通过一种标本得出的气温结果与另一种不相关标本（比如冰芯）得出的温度是否匹配。

　　The new data may become another flash point in the debate over the cause of rising temperatures. Many scientists blame increased emissions of greenhouse gases such as carbon dioxide, or CO2. Others disagree, contending that natural factors, such as an increase in cloud cover, are at play.

　　这一新的研究成果可能再次引发关于气候变暖原因的讨论。许多科学家认为，二氧化碳等温室气体排放增多是罪魁祸首。另外一些人则认为，是云量的增加等自然因素在作怪。