Air, earth, and water—contributions of JC Doran to boundary layer meteorology

Chris Doran's career in atmospheric sciences spanned three decades, during which he made strong contributions to boundary layer meteorology, particularly in complex terrain environments. His earliest work was in atmospheric dispersion, where he took advantage of observations using the diffusion grid on the Hanford Site in southeastern Washington to advance understanding of atmospheric dispersion. Efforts to understand effects of turbulence on dispersion in the moderately complex terrain of the Hanford Site led him to tackle the particularly challenging problem of nocturnal turbulent flows on slopes, and nocturnal turbulence was a topic to which he returned several times during his career. In the 1980s the U.S. Department of Energy instituted the Atmospheric Studies in Complex Terrain (ASCOT) program, through which he emerged as a national leader in the conceptual design and deployment of field measurement programs to study boundary layers in areas of complex terrain. In the 1990s, with DOE's emerging interest in climate change research, he turned his experience in complex-terrain boundary layers to the study of the response of the atmospheric boundary layer to inhomogeneous surfaces. Through DOE's Atmospheric Science Program (ASP) and Atmospheric Radiation Measurement (ARM) Program, he led multi-agency field campaigns to study effects of sharp local variations in vegetation and soil moisture on boundary layer structure (e.g., the Boardman Regional Flux Experiment) and the vertical mixing process itself in complex environments (e.g., the Vertical Transport and Mixing Experiment, or VTMX, in Salt Lake City). Results of the latter study, which was carried out jointly with the independently sponsored Urban 2000 campaign led by Jerry Allwine, made substantial contributions both to understanding both the diurnal cycle of vertical mixing in complex flow environments and mixing processes in urban canyons. VTMX was a pioneering study in that it is now widely acknowledged that understanding vertical mixing is necessary to accurately describe the life cycle atmospheric aerosols and their role in climate feedbacks. In the 2000s, Doran continued his leadership of boundary layer studies in work that ranged from boundary layer effects on aerosols in the vicinity of Mexico City to the impact of surface variability on arctic boundary layer clouds. This presentation will review his work, its influence, and the impact of his leadership over the course of his notable career.