The impact of natural aerosols on Atlantic tropical cyclone (TC) development is an important subject for better understanding and forecasting TC intensification, structure, and precipitation. This study will execute a comprehensive and systematic investigation of the role of natural aerosols on the Atlantic TC development, which includes marine aerosols and dust aerosols. The aerosol activation as cloud condensation (CCN) and ice nuclei (IN) and the interactions of these processes with TC dynamics and structure will be examined. The research aims to address the following science questions: 1). How do cloud nucleation processes as modulated by natural aerosols influence the intensity and structure of a TC by modifying the latent heat distribution and vorticity budget? 2). How sensitive is the TC intensity and structure to variations in the aerosol properties such as spatial distribution, concentration, size distribution, and chemical composition? 3). What is the relative importance of aerosols compared to other large-scale ambient thermodynamic and dynamic conditions in the TC evolution?
Numerical simulations using the Weather Research and Forecasting model 3.2 coupled with an atmospheric chemistry module (WRF-Chem) will be conducted. The WRF-Chem includes aerosol emission schemes, a radiative transfer scheme accounting for aerosol optical properties, and a dual moment microphysics scheme that will be modified to include several state-of-the-art CCN and IN activation schemes accounting for characteristics of dust and marine aerosols. Three real tropical cyclone cases will be chosen to examine the impact of marine and dust aerosols on storm development. Reanalysis products, satellite data sets, and in situ measurements will be used for model initialization, boundary forcing, and comparison with the simulations. Sensitivity tests will be performed to evaluate the model fidelity, elucidate the individual contribution from relevant physical processes, examine the sensitivity of these processes to aerosol properties, and compare the relative importance of aerosols to other large-scale environmental conditions.
Intellectual merit: The research will comprehensively address the impact of marine and dust aerosols on Atlantic TC evolution under representative environmental conditions through integrating observational data analyses and numerical simulations. This research will provide critical insights into the role of aerosol characteristics on the TC intensity and structure evolution and examine its importance relative to other physical processes.
Broader impacts: The study will contribute to the development of improved quantitative forecasts of TC intensity, structure, and rainfall. This research also supports the professional development of a female scientist who has recently completed her Ph.D. and also the education and training of a graduate student in remote sensing and numerical simulation of TC.
