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.
