Structural Analysis of Tropical Cyclones by the APAR Observing Simulator: A Comparison Study

As the Earth’s climate continues to warm, recent studies suggest that hurricanes will become increasingly more powerful. Scientists are challenged to understand intensifying complex storms to mitigate impending disasters. Remote sensing instruments have been developed to aid in deciphering storm microphysics and kinematics, yet, many limitations have hindered the comprehensive analyses of tropical cyclones. The Airborne Phased Array Radar (APAR) represents a groundbreaking advancement in hurricane research and forecasting. This next-generation airborne radar will provide agile scanning capabilities allowing a deeper understanding of the intricacies of atmospheric phenomena. The development of modern technology enables dual Doppler and dual polarimetric capabilities, ideal for analyzing convective systems. To support APAR’s development, the APAR Observing Simulator (AOS) was created to generate radar moments in realistic weather simulations of high-impact weather events. This tool replicates the expected APAR capabilities by utilizing the proposed, advanced scanning techniques. As such, by leveraging the advantages of APAR, the structure of tropical cyclones can be further examined. This project investigates and compares the structure of tropical cyclones as sampled by APAR to the Tropical Rainfall Measurement Mission Precipitation Radar as documented in the literature, and observations made by the NOAA Tail Doppler Radar. The comparison of these other platforms to APAR is through radar reflectivity, but APAR’s advanced capabilities allow for further investigation with the use of the dual-polarization variables. One such application is through the use of Particle Identification tools that allow for the classification of hydrometeor types, which in this work are constructed by simulating C-130 flights through an idealized hurricane simulation. The structure of hydrometeor classifications is displayed as Cumulative Frequency by Altitude Diagrams. The enhanced information about the tropical cyclone structure with simulated APAR data reveals significantly greater detail compared to earlier observations and provides a more informed structural analysis. This includes refined reflectivity values and distinct features unique to various segments of tropical cyclone structure. In this study, APAR’s potential to significantly improve the understanding of tropical cyclone structure is highlighted and points to the potential for providing better observations to help improve the accuracy of future hurricane forecasts.