A Lagrangian investigation of stable water vapor isotopes in deep convective systems

稳定水同位素已被证明是研究气候系统的有用工具，并在从古气候到地下水水文学的许多学科中提供了重要的见解。此外，稳定水同位素有可能进一步加深我们对对流动力学的理解，尽管这是一条相对较少探索的研究道路。在解释同位素数据时经常出现的问题之一是，关于大气过程如何影响降雨和水蒸气的同位素组成，人们仍然知之甚少。这项研究的主要目的是更深入地了解不同的对流过程如何影响水汽的同位素组成。这将通过同位素云解析模型和拉格朗日粒子扩散模型的组合来实现。这些模式将被用来模拟辐射-对流平衡的深对流系统。新的拉格朗日诊断将被用来专门关注对流系统的上升气流、下降气流和冷池，并研究这些动力学特征如何影响大气水汽同位素。这项研究的结果有望有助于解释过去和现在用于研究地球气候的同位素观测。更广泛的影响包括培训一名研究生，为两名本科生提供研究机会，以及与OʻAhu岛上的当地社区开展一些外展活动。该项目由美国国家科学基金会物理和动态气象学项目和既定的激励竞争研究计划共同资助。该奖项反映了美国国家科学基金会的法定使命，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。

Stable water isotopes have proved to be useful tools in the study of the climate system and have provided important insights in many disciplines, from paleoclimate to groundwater hydrology. In addition, stable water isotopes have the potential to further our understanding of convective dynamics, although this has been a relatively less explored research path. One of the problems that often arise in the interpretation of isotope data is that much is still unknown about how atmospheric processes affect the isotopic composition of rainfall and water vapor. The main goal of this research is to provide a deeper understanding of how different convective processes influence the isotopic composition of water vapor. This will be achieved through a combination of an isotope-enabled cloud resolving model and a Lagrangian particle dispersion model. The models will be used to simulate deep convective systems in radiative-convective equilibrium. Novel Lagrangian diagnostics will be employed to focus specifically on the updrafts, downdrafts, and cold pools of convective systems, and investigate how these dynamical features affect atmospheric water vapor isotopes.The results of this research are expected to help in the interpretation of isotope observations used to study the Earth’s climate both in past and present conditions. Broader impacts include training of a graduate student, research exposure for two undergraduate students, and a number of outreach activities with local communities across the island of Oʻahu.This project is jointly funded by NSF Physical and Dynamic Meteorology Program and the Established Program to Stimulate Competitive Research (EPSCoR).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.