Collaborative Research: P2C2 -- Statistical estimation of past ice sheet volumes from paleo-sea level records

ppi建议开发一个统计模型，用于根据当地海平面变化的地质指标推断过去的全球平均海平面（GSL）和冰盖体积。该模型将采用贝叶斯统计框架，将地质观测及其不确定性与与不同融水来源相关的时空海平面格局的地球物理模型结合起来。本研究的重点是三个方面的具体应用：(1)评估13万~ 11.5万年前末次间冰期不同冰盖对高GSL的贡献；(2)评估末次盛冰期至今的冰原历史，特别是估算这段时间内的净冰量变化，并评估约1.43万年前劳伦泰德和南极冰原对融水脉冲1a的相对贡献；(3)在第四纪和上新世的更大范围内，研究南北半球冰量与古气候代用物之间的关系。过去冰盖对气候变化响应的地质记录可以作为检验不同气候情景下冰盖动力学正演物理模型的关键数据源。本项目开发的模式将努力综合这样一个数据集，评估其相关的不确定性，并利用它来加强对关键气候参数（如极地和极地周围温度）与冰盖稳定性之间关系的理解。

The PIs propose to develop a statistical model for inferring past mean global sea level (GSL) and ice sheet volumes from geological indicators of changes in local sea levels. This model will employ a Bayesian statistical framework to combine geological observations and their uncertainties with a geophysical model of the spatial and temporal sea level patterns associated with different meltwater sources. The proposed work focuses on three specific applications: (1) evaluating the contribution of different ice sheets to high GSL during the Last Interglacial stage, ~130-115 thousand years ago; (2) assessing ice sheet history from the Last Glacial Maximum (LGM) to the present, in particular estimating the net ice volume change across this time interval and assessing the relative contributions of the Laurentide and Antarctic ice sheets to meltwater pulse 1a at ~14.3 thousand years ago; and (3) over a broader sweep of the Quaternary and Pliocene, investigating the relationship between Northern and Southern hemisphere ice volumes and paleoclimate proxies.The geological record of past ice sheet responses to climate change can serve as a key data source for testing forward physical models of ice sheet dynamics under different climate scenarios. The model developed in this project will be an effort to synthesize such a data set, evaluate its associated uncertainties, and employ it to strengthen understanding of the relationship between key climate parameters (such as polar and circum-polar temperatures) and ice sheet stability.