Collaborative Research: Determining the Role of Ocean Dynamics in Atlantic Sea Surface Temperature Variations Using a Hierarchy of Coupled Models

合作研究：使用耦合模型层次结构确定海洋动力学在大西洋表面温度变化中的作用

• 批准号: 2219707
• 负责人: Martha Buckley
• 金额: $ 31.96万
• 依托单位: George Mason University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2219707&HistoricalAwards=false
• 关键词: Collaborative; Research; Determining; Role; Ocean

Observations and models indicate that Atlantic sea surface temperatures (SSTs) exhibit significant low- frequency (interannual to decadal) variability, and a significant portion of these variations is related to internal variations of the climate system. However, the origin of these internal Atlantic SST variations is yet to be fully understood. This project will develop a hierarchy of coupled models in which various oceanic processes are disabled; comparing model pairs will enable the role of one-dimensional and three-dimensional ocean dynamics to be separated robustly, as well the separate roles of wind and buoyancy forcing in creating dynamical ocean variations. Much of the literature on decadal Atlantic SST variations is focused rather narrowly on the Atlantic Multidecadal Variability (AMV) and the role of the atmosphere and the ocean therein. Instead of focusing on one specific mode (e,g., the AMV), this research will isolate the modes of Atlantic SST variability related to specific oceanic processes, throughout the Atlantic basin on multiple time scales. This variability impacts regional and global climate, including temperatures across North America and Europe, rainfall in the Sahel region, and frequency and intensity of Atlantic hurricanes. Improved knowledge of low-frequency SST variability is essential for efforts aimed at climate predictions on seasonal to decadal time scales. Understanding the respective roles of atmospheric forcing and ocean dynamics in setting SST anomalies has implications for predictability of SSTs, as higher predictability is expected if ocean dynamics play a dominant role, and practical questions regarding the importance of monitoring ocean currents as part of a decadal prediction system. This project will also advance statistical methods for analysis of climate data by providing codes for covariance discriminant analysis to the broader community. This proposal will support a graduate student at WHOI and a postdoctoral researcher at NC State for a year each. The proposal will also support 2 female early career PIs. Lead PI Buckley is a Co-Leader of a mentoring group for Mentoring Physical Oceanography Women to Increase Retention (MPOWIR). The PIs will also engage in K-12 Science-Technology- Engineering-Math (STEM) education by serving as mentors and judges for the local public school annual science fairs.The goal of this project is to disentangle the roles of atmospheric forcing and various ocean dynamical processes in Atlantic SST variability and predictability on interannual-to-decadal time scales. In order to achieve this goal, a hierarchy of coupled models will be developed using the Community Earth System Model version 2 (CESM2). The model hierarchy will include ocean model components of varying complexity and comparing model pairs will enable the team to quantitatively determine the roles of specific aspects of ocean dynamics, including one-dimensional processes (vertical mixing, interannual mixed layer depth variations, entrainment) and three-dimensional ocean dynamics (including wind and buoyancy-driven processes), on driving SST variability. A rigorous statistical technique, called covariance discriminant analysis, will be applied to diagnose the leading differences in Atlantic SST variance between model pairs, thus elucidating the impact of specific ocean processes on Atlantic SST variability. Additionally, a comparison of the predictability of Atlantic SST between models in the hierarchy, will help elucidate the role of oceanic processes in predictability.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.

观察结果和模型表明，大西洋海面温度（SST）表现出明显的低频（年间到衰老）的可变性，并且这些变化的很大一部分与气候系统的内部变化有关。但是，这些内部大西洋SST变化的起源尚未完全理解。该项目将开发一个耦合模型的层次结构，其中各种海洋过程被禁用；比较模型对将使一维和三维海洋动力学的作用可靠地分离，以及风和浮力强迫在创造动态海洋变化中的独立作用。关于十年大西洋SST变化的许多文献都集中在大西洋多年代变异性（AMV）以及大气和海洋中的作用上。这项研究不是专注于一种特定模式（e，g。，the AMV），而是将与特定海洋过程相关的大西洋SST变异模式隔离到整个大西洋盆地，以多个时间尺度隔离。这种可变性会影响区域和全球气候，包括北美和欧洲的温度，萨赫勒地区的降雨以及大西洋飓风的频率和强度。对低频SST可变性的提高知识对于针对季节性至际时间尺度的气候预测的努力至关重要。了解大气强迫和海洋动力学在设定SST异常中的各自作用对SST的可预测性有影响，因为如果海洋动力学起主要的作用，则预期可预期的可预测性以及有关监测洋流作为衰减预测系统一部分的重要性的实用问题。该项目还将通过为更广泛的社区提供协方差分析的代码来推进统计方法，以分析气候数据。该建议将为WHOI的一名研究生和NC State的博士后研究员提供支持一年。该提案还将支持2个女性职业生涯。 Pi Buckley Lead Pi Buckley是指导组织的指导小组的共同领导者，以增加保留率（Mpowir）。 PIS还将通过担任当地公立学校年度科学博览会的导师和法官来从事K-12科学技术 - 工程学教育。该项目的目的是消除大气强迫的作用，并在Atlantic SST的各种海洋动力学过程中的角色，以及对年间到十大时间量表的大西洋SST变异性和可预测性。为了实现这一目标，将使用社区地球系统模型2（CESM2）开发耦合模型的层次结构。模型层次结构将包括各种复杂性的海洋模型组成部分，比较模型对将使团队能够定量确定海洋动态特定方面的作用，包括一维过程（垂直混合，年间混合层凹陷变化，夹带）和三维的海洋动力学（包括风力和浮标的过程），包括风力和浮动过程），即驱动式驱动式驱动器。一种严格的统计技术，称为协方差判别分析，将应用于诊断模型对之间大西洋SST方差的主要差异，从而阐明了特定的海洋过程对大西洋SST差异的影响。此外，比较了层次结构模型之间大西洋SST的可预测性，将有助于阐明海洋过程在可预测性中的作用。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响标准通过评估来进行评估的支持。