Professor Bornstein’s research focuses on the observation and numerical simulation of polluted urban and coastal planetary boundary layers, with particular emphasis on urban heat islands, building–atmosphere interactions, and the influence of metropolitan areas on precipitation and convective storms. Drawing on extensive analysis of the landmark New York City observational dataset, he has developed a comprehensive physical understanding of urban mesometeorology, encompassing temperature and humidity structure, wind fields, sea-breeze modification, and pollutant dispersion. He has contributed substantially to the development and evaluation of integrated WRF/Urban modelling systems, while his leadership of the SURF project has further advanced understanding of urban convection and haze. With an h-index of 28 and more than 4,200 citations, his influence has been reinforced by extensive editorial service, including more than three decades as Executive Editor or Editor Emeritus of Atmospheric Environment. His representative publications, spanning foundational observations of the New York City urban heat island, the URBMET model, urban influences on convective thunderstorms, integrated WRF/urban modelling, and the SURF synthesis of urban convection and haze, reflect a career that helped establish urban meteorology as a quantitative and predictive science with enduring relevance to air-quality management, urban planning, and climate resilience.