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The time series of free surface elevation measured in and outside the shadow zone were compared and analyzed in the time-frequency domain by employing the continuous wavelet transform. Regardless of the conditions of the ERF wave in the shadow zone, an increase in magnitude of energy is noticeable not only in the peak frequency within a range of approximately 0.8 to 1 Hz but also in the low-frequency range of around 0.1 Hz corresponding to second up to third crest of the leading wave. To determine the effective frequency of ERF waves and evaluate their runup characteristics, we applied a new method of describing the ERF wave, which consists of linear superposition of two solitary waves. As a result, the ERF waves show the same trend in runup characteristics as for solitary waves. 

On September 1 2019, Hurricane Dorian made landfall in Elbow Cay in the Bahamas with sustained winds of 295 km/h and a central pressure of 910 mb, with subsequent landfalls in Marsh Harbour and Grand Bahama Island, where it stalled for two days. This paper presents field observations of Dorian’s coastal hazards and impacts on the built environment in these locales, collected by the Structural Extreme Events Reconnaissance (StEER) Network. Data were collected using a mixed methodological approach: (1) surveying high-water marks and inundation extent, including an approximately 8 m high water mark in Marsh Harbour, (2) conducting surface-level forensic assessments of damage to 358 structures, and (3) rapidly imaging 475 km of routes using street-level panoramas. Field observations are complemented by a debris field analysis using high-resolution satellite imagery. Observed performance reiterates the potential for well-confined, elevated construction to perform well under major hurricanes, but with the need to codify such practices through the addition of storm surge design provisions and an increase in the design wind speeds in the Bahamas Building Code. This study further demonstrates the value of robust reconnaissance infrastructure for capturing perishable data following hurricanes and making such data rapidly available using publicly accessible platforms.