Collaborative Research: P2C2--Insights into Tropical Pacific Climate from Paleoproxy Data Assimilation into an Intermediate Complexity Dynamical Model

该项目大体上寻求重建和解释过去一千年来热带太平洋应对辐射强迫的状况。这将通过将来自珊瑚和树木的高分辨率古替代物同化到动态厄尔尼诺南方涛动(ENSO)模式中来实现。动力信息古重构将被研究以解决以下科学问题：(I)热带太平洋如何响应外部辐射强迫(ERF)；(Ii)ENSO是否表现出类似于制度的行为，以及ENSO的不规律性主要是由于混沌或噪声驱动的动力学；(Iii)ENSO在过去是如何变化的；以及(Iv)动力学ENSO模式能否改善热带太平洋的古替代物重构。这些问题与可预测性和年代际变化有关，并与理解ENSO及其过去、现在和未来的影响有关。利用记录在案的预测技术，将信息加入到ENSO动力模式的古气候重建中，是一种新的方法，可能会增强对热带太平洋代理记录的解释。潜在的更广泛的影响包括随着时间的推移对ENSO行为的更好理解，在研究项目中对本科生的支持，以及通过哥伦比亚大学和马里兰大学成熟的外展努力向公众宣传。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

This project broadly seeks to reconstruct and interpret the state of the tropical Pacific over the last millennium in response to radiative forcing. This will be accomplished by assimilating high-resolution paleo-proxies from corals and trees into a dynamical El Nino Southern Oscillation (ENSO) model.Dynamically informed paleo-reconstructions will be studied to address the following science questions: (i) how does the tropical Pacific respond to external radiative forcing (ERF); (ii) does ENSO exhibit regime-like behavior and is ENSO irregularity primarily due to chaotic or to noise-driven dynamics; (iii) how has ENSO varied in the past; and (iv) can a dynamical ENSO model improve paleo-proxy reconstructions of the tropical Pacific. These questions have implications for predictability and decadal variability and are relevant to understanding ENSO and its impacts, past, present and future. Adding information into paleoclimate reconstructions from a dynamical model of ENSO with documented predictive skill is a novel approach and may enhance interpretation of Tropical Pacific proxy records. The potential Broader Impacts include improved understanding of ENSO behavior over time, support of undergraduate students in the research project, and outreach to the public through well-established outreach efforts at Columbia University and the University of Maryland.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.