Transport Dynamics of the Northeast Pacific In a Changing Climate

气候变化下东北太平洋的运输动态

• 批准号: 1948627
• 负责人: Emanuele Di Lorenzo
• 金额: $ 48.88万
• 依托单位: Georgia Tech Research Corporation
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-03-15 至 2023-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1948627&HistoricalAwards=false
• 关键词: Transport; Dynamics; Northeast; Pacific; Changing

Over the last decades, the Northeast Pacific (NEP), has experienced dramatic changes in its climate with the occurrence of a sequence of record-breaking temperature extremes between 2013-2019, such as the multi-year 2013-15 Northeast Pacific marine heatwave, the strong 2015-16 El Niño, and more recently the ongoing 2019 Alaskan heatwave. The resulting changes in temperature and eddy-scale ocean transport dynamics (e.g. cross-shore, alongshore, upwelling) in the Gulf of Alaska (GOA) and California Current System (CCS) led to dramatic ecosystem impacts that include harmful algal blooms along the coasts, low primary productivity, massive die offs of mammals and birds. Despite advances in our understanding of the large-scale Pacific changes, it remains unclear how regional transport dynamics of the GOA and CCS are responding to the observed climate extremes and trends in decadal climate variability in the NEP, and what changes in transport statistics are expected under anthropogenic climate forcing. Key Questions: (Q1) How did the amplification of the regional climate variance in the Northeast Pacific over the last decades impact eddy-scale transport dynamics (e.g. alongshore, cross-shore, upwelling) in the California and Gulf of Alaska circulation systems? (Q2) What are the Pacific largescale drivers that control the regional ocean transport statistics during the recent temperature extremes (2013-2019), and are the changes in transport significant (e.g. an extreme) in the context of historical long-term variability (1950-2000)? (Q3) How are ecologically-relevant transport statistics in the Northeast Pacific expected to change under anthropogenic forcing (2050-2100), and are these changes consistent with what occurred during the recent extremes (2013-2019)? The goal of this research is to identify and estimate the response of ecologically-relevant eddyscale transport dynamics in the Northeast Pacific to (GOAL1) recent amplifications of large-scale climate forcing (e.g. extremes, trends, decadal variability), and (GOAL2) projected changes in anthropogenic climate change as inferred from large-ensemble of individual Earth System Models (ESMs) that allow to separate the internal vs forced variability. Two female Ph.D. students will be trained and mentored. The PI will share this research in his ongoing interdisciplinary research/leadership activities in the California-LTER, PICES, and US CLIVAR. The high-resolution regional climate ensemble archive generated in this study will be a unique asset to the marine research community in the Northeast Pacific. The PI will work with the CCE-LTER team to make the model output available for interdisciplinary studies and to develop a set of Linear Inverse Model tutorials to help marine ecosystem scientists apply this methodology to explore ecological dynamics.The approaches & TASKs of the investigation will include (T1) a 10-member ensemble of high-resolution regional coupled ocean-atmosphere model historical simulations of the Northeast Pacific (1950-2019) with a passive tracers transport module to downscale the impact of large-scale Pacific climate forcing on regional transport dynamics in the GOA and CCS, (T2) a set of Linear Inverse Models (LIMs) to identify and quantify the effects of large-scale drivers on ecologically-relevant regional transport statistics inferred from the passive tracers, (T3) the use of large ensemble simulations of individual ESMs (e.g. CESM, GFDL ESM2M) under the SSP5-8.5 or equivalent scenario as input to the LIM to investigate how anthropogenic forcing is projected to impact the targeted transport statistics in the context of internal climate variability. The recent increase in climate variance and ecosystem synchrony in the Northeast Pacific, together with the ecological and societal impacts of the temperatures extremes of the 2013-15 Northeast Pacific marine heatwave, the strong 2015-16 El Niño, 2019 Alaskan heatwave, raise concern and questions of the role of natural and anthropogenic forcing in the regional oceanography of the Northeast Pacific. Eddy-scale transport dynamics (e.g. alongshore, cross-shore, upwelling) have long been recognized as a key driver of marine ecosystem change, yet the response of these dynamics to a changing climate remains unclear. This work will provide understanding on how the recent trends in the climate variance of ecological drivers relates to long-term historical variability and to anthropogenic forcing.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.

在过去的几十年里，东北太平洋（NEP）的气候经历了巨大的变化，2013年至2019年期间出现了一系列破纪录的极端气温，例如2013-15年的多年东北太平洋海洋热浪， 2015-16 年强烈的厄尔尼诺现象，以及最近持续的 2019 年阿拉斯加热浪，导致了温度和涡流规模海洋运输动力学的变化（例如跨岸、阿拉斯加湾 (GOA) 和加利福尼亚洋流系统 (CCS) 的沿海上升流导致了巨大的生态系统影响，包括沿海藻类大量繁殖、初级生产力低下、哺乳动物和鸟类大量死亡，尽管我们的认识有所进步。关于太平洋大规模变化，目前尚不清楚GOA和CCS的区域运输动态如何响应观测到的极端气候和NEP中十年间气候变化的趋势，以及在人为气候强迫下预计运输统计数据会发生什么变化。钥匙问题：（问题 1）过去几十年东北太平洋区域气候变化的扩大如何影响加利福尼亚和阿拉斯加湾环流系统的涡流输送动态（例如沿岸、跨岸、上升流）（问题 2）？ ）在最近的极端温度（2013-2019）期间控制区域海洋运输统计的太平洋大规模驱动因素是什么，以及在历史背景下运输的显着变化（例如极端）长期变化（1950-2000 年）？（Q3）在人为强迫作用下（2050-2100 年），东北太平洋与生态相关的运输统计数据预计会发生怎样的变化，这些变化与近期极端事件（2013 年）期间发生的情况是否一致？ ) -2019)? 这项研究的目标是确定和估计东北太平洋生态相关的涡鳞输送动力学对 (GOAL1) 最近放大的响应大规模气候强迫（例如极端、趋势、年代际变率）的影响，以及（目标2）根据单个地球系统模型（ESM）的大型集合推断出的人为气候变化的预测变化，这些模型可以区分内部变率和强迫变率。两名女博士生将接受培训和指导，他将在加州 LTER、PICES 和 US CLIVAR 正在进行的跨学科研究/领导活动中分享这项研究。本研究生成的高分辨率区域气候集合档案将成为东北太平洋海洋研究界的独特资产，PI 将与 CCE-LTER 团队合作，使模型输出可用于跨学科研究并开发一套模型。线性逆模型教程，帮助海洋生态系统科学家应用这种方法来探索生态动态。调查的方法和任务将包括 (T1) 东北地区高分辨率区域耦合海洋-大气模型历史模拟的 10 名成员集合太平洋（1950-2019），采用被动示踪剂输运模块，以缩小大规模太平洋气候强迫对 GOA 和 CCS 区域输运动态的影响，(T2) 一组线性逆模型 (LIM)，用于识别和量化大规模驱动因素对从被动示踪剂推断的生态相关区域运输统计数据的影响，（T3）使用单个 ESM 的大型集合模拟（例如 CESM， GFDL ESM2M）在 SSP5-8.5 或同等情景下作为 LIM 的输入，以研究在内部气候变化的背景下，人为强迫如何影响目标运输统计数据。加上2013-15年东北太平洋海洋热浪极端气温的生态和社会影响、2015-16年强烈的厄尔尼诺现象、2019年阿拉斯加热浪引起人们的关注自然和人为强迫在东北太平洋区域海洋学中的作用问题长期以来一直被认为是海洋生态系统变化的关键驱动因素。这些动态对气候变化的影响仍不清楚。这项工作将有助于了解生态驱动因素的气候变化如何反映最近的趋势，与长期历史变化和人为强迫有关。该奖项是 NSF 的法定使命，并被认为是值得的。通过评估提供支持基金会的智力价值和更广泛的影响审查标准。

项目成果

The Continuum of Northeast Pacific Marine Heatwaves and Their Relationship to the Tropical Pacific

东北太平洋海洋热浪的连续体及其与热带太平洋的关系

• DOI: 10.1029/2020gl090661
• 发表时间: 2021
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Xu, Tongtong;Newman, Matthew;Capotondi, Antonietta;Di Lorenzo, Emanuele
• 通讯作者: Di Lorenzo, Emanuele