P2C2: Synthesis of Holocene Proxy Climate Records from Western North America

该项目的总体目标是开发一种新的主要代用气候记录综合方法，包括来自北美西部和邻近太平洋的各种代用气候记录类型，以建立一个统一的数据库，以记录全新世气候变化在百年至千年时间尺度上的时空格局。重建过去气候依赖于来自大量站点的各种证据来捕捉气候变化的多样性特征和空间异质性。为了系统地研究过去气候变化的时空格局，并定量表征可能揭示的突出格局，需要一个空间分布的相关古气候时间序列网络。该项目将连接极地和非极地地区，并开发古气候数据集，通过组装一个从北极到热带的现有古气候记录的主要新数据库来测试模型结果。该区域的尺度足以研究北太平洋东缘海气环流的主要特征，也足以研究全新世最强的气候强迫——轨道变化对气候的纬向响应。代理数据，包括数据库和对其他现有证据的系统审查，将与通过综合气候系统瞬态演化（TraCE）项目进行的模拟实验的现有输出进行比较。以前的代用记录的合成研究了特定时间片的大尺度模式，主要依赖于陆地记录的花粉，或者强调大陆边缘的海面温度。根据来自更广泛的代理类型的证据，包括来自海洋和陆地档案的物理、化学和生物证据，确定在多大程度上可以辨别出更细尺度的格局，需要作出重大努力，最大限度地利用以前的研究。很大一部分相关的已发表数据尚未收集，需要与个别科学家合作，以产生一个全面的、专家知情的产品。一旦适当地组装和质量控制，一个机器可读的代理气候时间序列数据库就可以很容易地进行分析，以量化最突出的模式。该项目有可能为更广泛的社区提供一套大型古气候信息数据集，用于识别气候模式和解决知识空白。该项目还将支持两名早期职业科学家。

This project generally aims to develop a major new synthesis of proxy climate records that includes a full range of proxy types from western North America and the adjacent Pacific Ocean to build a unified database, with the goal of documenting spatial-temporal patterns of Holocene climate change on multi-centennial to millennial time scales.Reconstructing past climate relies on a variety of evidence from a large number of sites to capture the diverse features and spatial heterogeneity of climate change. To systematically investigate the spatial-temporal pattern of past climate changes and to quantitatively characterize the prominent patterns that might be revealed requires a spatially distributed network of relevant paleoclimate time series. This project will link polar and non-polar regions and to develop paleoclimate data sets for testing model outcomes by assembling a major new database of existing paleoclimate records spanning from the Arctic to the tropics. The scale of the region is sufficient to investigate the primary features of ocean-atmospheric circulation along the eastern margin of the North Pacific and to study the latitudinal response of climate to orbital changes, the strongest climate forcing of the Holocene. The proxy data, including the database and a systematic review of other available evidence, will be compared with the available output from modeling experiments through the Synthesizing the Transient Evolution of the Climate System (TraCE) project.Previous syntheses of proxy records have examined broad-scale patterns at specific time slices and have primarily relied on pollen from terrestrial records or have emphasized sea-surface temperatures from continental margins. Determining the extent to which finer-scale patterns might be discerned based on evidence from a wider variety of proxy types, including physical, chemical and biological evidence from both marine and terrestrial archives, requires a major effort to maximize the utility of previous studies. A large portion of relevant published data has not yet been assembled and requires collaboration with individual scientists to generate a comprehensive, expert-informed product. Once properly assembled and quality controlled, a machine-readable database of proxy climate time series can be readily analyzed to quantify the most prominent patterns.The project offers the potential for providing a large data set of paleoclimate information available to the wider community for use in recognizing patterns of climate and addressing gaps in knowledge. The project would also support two early career scientists.