Insights into climate change and reliability of GloSAT from integrating climate proxy, model and instrumental sources

气候代用指标不仅用于延长仪器观测期之前的记录，而且在评估仪器观测记录本身方面也有价值（例如，全球趋势：安德森等人，2013;印度洋SST：Pfeiffer等人，2017）。这个博士将应用这种比较的时期和地区，从代理的洞察力将是最有价值的。一个重点将是欧洲在早期仪器期间（前1900年，特别是GloSAT的新扩展1850年之前），不同的温度计曝光有助于夏季温度偏差，有丰富的夏季敏感的复制良好的树木年轮数据补充文件证据。另一个重点将是热带温度趋势与珊瑚记录的信息进行比较（PAGES 2k Consortium 2017）。新的方法将加强该项目，包括利用来自上一个千年再分析（Tardif等人，2018）的信息，并将改进的方法应用于树轮分析（无信号区域曲线标准化），以产生更可靠的百年趋势。毫无疑问，基于代理的多世纪趋势存在重大的不确定性，博士项目将探索这一趋势。即使这些都太大，限制GloSAT仪器的不确定性，说，1800年至今，代理也将提供独立的信息十年-多十年的温度变化和博士项目将利用这一点来评估仪器的变化在可比的时间跨度。比如说，在不同的数据集之间，1800-1850年和1850-1900年的温度变化存在差异，气候代理可能有助于解决这些问题。总体结果将是对案例研究区域的GloSAT温度和优化气候变化信息进行独立评估。参考文献Anderson et al.（2013）全球变暖在过去130年的独立记录。地球物理学家。保留信函：40，189-193，doi：10.1029/2012GL054271.PAGES2k Consortium（2017）A global multiproxy database for the temperature reconstructions of the Common Era. Sci. Data，4，170088，doi：10.1038/sdata.2017.88 Pfeiffer et al.（2017）Indian Ocean corals reveal critical role of World War II bias for twenty世世纪warming estimates. Scientific Reports 7，14434，https://doi.org/10.1038/s41598-017-14352-6Tardif et al.（2018）Last Millennium Reanalysis with an expanded proxy database and seasonal proxy modeling，Clim.过去的讨论，https://doi.org/10.5194/cp-2018-120

Climate proxies are not just for extending the record before the instrumental period but also have value in assessing the instrumental record itself (e.g. global trends: Anderson et al. 2013; Indian Ocean SST: Pfeiffer et al. 2017). This PhD will apply such comparisons to periods and regions where the insight from proxies will be most valuable. One focus will be Europe in the early instrumental period (pre-1900 and especially GloSAT's new extension before 1850) where different thermometer exposures contribute to summer temperature biases and there is a wealth of summer-sensitive well-replicated tree-ring data supplemented by documentary evidence. Another focus will be tropical temperature trends in comparison with information from coral records (PAGES 2k Consortium 2017). Novel approaches will strengthen the project, including utilising information from the Last Millennium Reanalysis (Tardif et al. 2018) and applying improved approaches to tree-ring analysis (signal-free Regional Curve Standardisation) to yield more reliable multi-centennial trends. There are undoubtedly significant uncertainties is the proxy-based multi-centennial trends which the PhD project will explore. Even where these are too large to constrain the GloSAT instrumental uncertainties from, say, 1800-present, the proxies will also provide independent information on decadal-multidecadal temperature variability and the PhD project will utilise this to evaluate the instrumental variations over comparable time-spans. For example, there are differences in temperature changes over 1800-1850 and 1850-1900 between different datasets and the climate proxies might contribute to resolving these issues.The overall outcome will be an independent evaluation of GloSAT temperature and optimised climate change information in the case study regions.ReferencesAnderson et al. (2013) Global warming in an independent record of the past 130 years. Geophys. Res. Lett., 40, 189-193, doi: 10.1029/2012GL054271.PAGES2k Consortium (2017) A global multiproxy database for temperature reconstructions of the Common Era. Sci. Data, 4,170088, doi: 10.1038/sdata.2017.88Pfeiffer et al. (2017) Indian Ocean corals reveal crucial role of World War II bias for twentieth century warming estimates. Scientific Reports 7, 14434, https://doi.org/10.1038/s41598-017-14352-6Tardif et al. (2018) Last Millennium Reanalysis with an expanded proxy database and seasonal proxy modeling, Clim. Past Discuss., https://doi.org/10.5194/cp-2018-120