The Climate Memory of Tropical Cyclones: Dimensions, Magnitude, Mechanisms for Generation and Removal, and Implications

该项目将在时间和空间上全面定义热带气旋（TC）的气候足迹（“记忆”），解释足迹的许多有趣和重要方面。具体而言，研究人员将(i)定义碳足迹结构的时空范围及其可变性；（ii）定义碳足迹产生和消除的机制以及这些机制在地理和时间上的可变性；（iii）通过碳足迹隐含的总能量度量量化碳足迹在气候中的作用；（iv）将碳足迹的总能量度量与其他气候运输机制进行比较。例如平均经向环流和斜压活动。研究人员将利用不同的再分析数据集和新的气候预报系统再分析和再预测（CFSRR）耦合再分析来量化足迹大小和驱动物理机制的不确定性，承认这些数据集的固有局限性。这项工作将弥合我们对“天气”（在这里是tc）和气候的理解之间的主要差距，而在自然界中并不存在这种差距。历史上的假设是，全球环流模式（GCMs）可以（充其量）广泛地参数化tc的大尺度影响，并且大尺度气候模拟不会受到实质性的影响。这项研究将详细地限定和量化这种影响以及这种假设的有效性。碳排放化合物在整个气候中的总体作用将被量化。该项目的更广泛影响包括提高了对TC在气候中的作用的理解。预测洪水、干旱和厄尔尼诺-南方涛动（ENSO）事件的能力取决于对上层海洋和大气边界条件的精确模拟，以及由此产生的大气遥相关模式。该项目将揭示由碳排放足迹引起的气候可预测性的总体潜在限制。它将培训研究生，并确保在会议、讲习班、研讨会、出版物和网站上广泛传播结果和发现。

This project will comprehensively define the climate footprint ("memory") of a tropical cyclone (TC) in time and space, explaining many fascinating and important aspects of the footprint. Specifically, the investigators will (i) define the temporal and spatial extent of the structure of the TC footprint and its variability, (ii) define the mechanisms for TC footprint generation and removal and the variability of those mechanisms geographically and temporally, (iii) quantify the role of TCs in climate through aggregate energy measures implied by the aggregate footprint, and (iv) compare the TC aggregate energy measures to other climate transport mechanisms, such as the mean meridional circulation and baroclinic activity. The investigators will utilize the varying reanalysis datasets and the new Climate Forecast System Reanalysis and Reforecast (CFSRR) coupled reanalysis to quantify the uncertainty in the footprint magnitude and the driving physical mechanisms, acknowledging the inherent limitations of such datasets.This work will bridge a major gap that exists between our understanding of "weather" (in this case TCs) and climate, when no such gap exists in nature. The assumption has been historically that the large-scale impacts of TCs can be (at best) broadly parameterized in Global Circulation Models (GCMs), and that the large scale climate simulation will not suffer substantially. The research will in detail qualify and quantify this impact and that assumption's validity. The aggregate role of TCs in climate as a whole will be quantified.The broader impacts of this project include an improved understanding of the TC role in climate. The ability to forecast floods, droughts, and El Nino-Southern Oscillation (ENSO) events is dependent upon the accurate simulation of the upper ocean and atmospheric boundary conditions, and the atmospheric teleconnection patterns that result. The project will shine a light on the overall potential limits of climate predictability as induced by the TC footprint. It will train graduate students and ensure wide dissemination of results and findings in conferences, workshops, seminars, publications, and websites.