Evaluating the Vertical Structure of Near-Coastal Meteorological Phenomena Around Urban Regions Using Uncrewed Aircraft Systems

The Earth's coastal environments are dynamic and intricate zones that play a pivotal role in global climate systems, biodiversity, economies, and human settlements. Approximately 40% of the global population lives within 100 km of a coastline. In the context of expanding urbanization and population growth in coastal areas, there are challenges related to air quality, heat island effects, pollution, and extreme weather events. Monitoring the atmospheric composition over these regions is vital for assessing air quality standards, devising pollution mitigation strategies, and enhancing public health outcomes. Beyond the direct impacts on urban areas, observing the atmosphere over these regions is a critical endeavor with implications for understanding climate change, predicting extreme weather events, safeguarding ecosystems, and supporting sustainable coastal development. Socioeconomic activities in coastal areas, such as tourism, fishing, shipping, and agriculture, depend heavily on weather and climate conditions. Accurate atmospheric observations are critical for both developing fundamental understanding on the physics and chemistry of coastal atmospheric phenomena, and for supporting improved prediction of weather in the coastal zone.

The interface between land, water, and manmade infrastructure leads to distinctive temperature gradients, wind patterns, moisture exchange, and pollution transport. In combination, these factors result in diverse weather patterns and localized climatic phenomena. Accurate observation and analysis of these atmospheric dynamics are essential for improving weather forecasts, enhancing climate models, and managing natural resources. Importantly, these phenomena can be highly localized and varying in space and time. Historically, observing networks in the coastal zone are limited, particularly over the water portion of the interface. These observing networks often consist of surface-based meteorological and air quality instrumentation, resulting in a lack of information on the vertical structure of key phenomena. In the current presentation, we will share insights into coastal processes gained through observational data collected by uncrewed aircraft systems (UAS). The University of Colorado Boulder UAS team partnered with collaborators from multiple institutions to collect detailed observations of the lower atmosphere in the coastal environment, including measurements of turbulence and mixing, aerosol size distributions, temperature, moisture, wind, and the evolution of cloud cover. These parameters are evaluated in the context of coastal phenomena including lake- and sea-breezes, an urban heat island, and local sources of pollution and aerosols. UAS observations were collected during the TRacking Aerosol Convection interactions ExpeRiment (TRACER) campaign conducted in the greater Houston environment in the summer of 2022, and the Wisconsin’s Dynamic Influence of Shoreline Circulations on Ozone (Wisco-DISCO) project, conducted in spring 2021 along the Lake Michigan shoreline. We will share insights gained from these campaigns and put the UAS observations into broader context, leveraging information from other sensing systems deployed as part of these projects, and as part of the nation’s coastal observing system.