COURAGE

Coast-Urban-Rural Atmospheric Gradient Experiment

1 December 2024 - 30 November 2025

Lead Scientist: Kenneth Davis

Observatory: AMF

Understanding the mechanisms governing the urban atmospheric environment is critical for informing urban populations regarding the impacts of climate change and associated mitigation and adaptation measures. Earth system (climate and weather) models have not yet been adapted to provide accurate predictions of climate and weather variability within cities, nor do they provide well-tested representations of the impacts of urban systems on the atmospheric environment. These limitations are largely due to limited field data available for testing and development of these models.

We will deploy an ARM mobile facility to the Mid-Atlantic region surrounding the city of Baltimore for the Coast-Urban-Rural Atmospheric Gradient Experiment (CoURAGE). This deployment will create a four-node regional atmospheric observatory network including Baltimore and its three primary surrounding environments – rural, urban, and bay.

CoURAGE investigators will study the interactions among the Earth’s surface, atmospheric boundary layer, aerosols and atmospheric composition, clouds, radiation, and precipitation at each site, and examine how the spatial gradients across the region interact to create the climate conditions in Baltimore.

This study will determine the degree to which Baltimore’s atmospheric environment depends on interactive feedbacks in the atmospheric system and conditions in Baltimore depend on the surrounding environment. Topics of interest include how urban land management exacerbates heat waves, the impact of winds from the surrounding environments, including a nocturnal low-level jet and bay breezes, on urban air pollution, and the impact of the urban heat island and aerosol production on heavy precipitation events. Understanding this integrated coast-urban-rural system quantitatively and with good accuracy and precision is critical to informing climate adaptation and mitigation efforts in the city of Baltimore. The understanding gained should be applicable to many similar coastal, midlatitude urban centers.

Another important objective of CoURAGE is to improve the representation of the climate of coastal cities in Earth systems models (ESMs). CoURAGE investigators will use the observations to test current ESMs, identify weaknesses, and work towards improved simulations of this complex environment.

The ARM mobile facility will be deployed in the city of Baltimore, complementing the Baltimore Social-Environmental Collaborative (BSEC), a U.S. Department of Energy urban integrated field laboratory (IFL). Ancillary sites will be deployed to rural Maryland northwest of the city, and to an island in Chesapeake Bay. The fourth node will be a long-term atmospheric observatory operated in Beltsville, Maryland by Howard University and the Maryland Department of the Environment. Measurements will be conducted for one year, with four intensive operational periods, one in each season, when the ancillary sites will be enhanced with additional balloon launches, tethered balloon system operation, and added atmospheric composition measurements.