Climate changepoint (homogenization) methods abound today, with a myriad of techniques existing in both the climate and statistics literature. Unfortunately, the appropriate changepoint technique to use remains unclear to many. Further complicating issues, changepoint conclusions are not robust to small perturbations in assumptions; for example, allowing for a trend or correlation in the series can drastically change conclusions. This paper is a review of the changepoint topic, with an emphasis on illuminating the models and techniques that allow the scientist to make reliable conclusions. Pitfalls to avoid are demonstrated via actual applications. The discourse begins by narrating the salient statistical features of most climate time series. Thereafter, single and multiple changepoint problems are considered. Several pitfalls are discussed en route and good practices are recommended. While the majority of our applications involve temperature series, other settings are mentioned.
翻译:气候变化点(同化)方法在今天繁多,气候文献和统计文献中都有各种各样的技术。 不幸的是,对许多人来说,使用的适当变化点技术仍然不清楚。更复杂的问题是,改变点结论对假设中的小扰动并不有力;例如,允许系列中的趋势或相关性可以极大地改变结论。本文件审查变化点专题,强调启发科学家能够作出可靠结论的模式和技术。通过实际应用可以证明需要避免的空洞。讨论始于说明大多数气候时间序列的突出统计特征。此后,审议了单一和多个变化点问题。在途中讨论了一些陷阱,建议了一些良好做法。我们的大部分应用都涉及温度序列,但提到了其他环境。