The Air Resources Laboratory’s (ARL) mission is to improve the ability of the Nation to protect human and ecosystem health and to support a vibrant economy through advanced atmospheric sciences and technologies. ARL’s research focus is on the surface of the Earth from a few feet below the soil up to 2-3 miles in the atmosphere, known as the boundary layer, which has a direct impact on people’s health and safety, business, and the environment. ARL studies the physical and chemical processes that occur in the boundary layer, on time scales spanning a few hours to several years.

ARL studies the mixing, exchange, and transformation of energy, moisture, trace gases and particles and contributes inputs to meteorological models and forecast operations that are vital in improving weather, climate and air quality forecasts. Primary applications include emergency response, homeland security, air quality, weather forecasts, climate outlooks, commerce and transportation. ARL’s vision is to effectively protect people, the environment, and commercial activities from atmospheric risks using the best available scientific understanding of boundary layer processes.

Primary Research Areas

Surface Atmosphere Exchange

  • Research processes and variables controlling heat and water vapor exchanges between land and atmosphere

Atmospheric Transport and Dispersion

  • Research main processes that drive transport and dispersion in the atmosphere
  • Improve the quality of and assess uncertainties/applicability of modeling tools

Boundary Layer Characterization

  • Improve accuracy of atmospheric models and other forecast and prediction tools to better understand the atmospheric boundary layer 
Image of the top half of the cover of Boundary Matters

July 24, 2025

ARL released the 2025 issue of Boundary Matters, our annual newsletter. Check features including:

  • HYSPLIT uses for emergency management preparations

  • 2025 meet the interns feature

  • A sneak peak into rapid-deploy towers designed and built at ARL

Young boy swimming underwater in a pool

July 21, 2025

Concerns over a chemical leak and a potentially explosive reaction led to the Weather Forecasting Office in State College, PA running the HYSPLIT model for the Columbia County Emergency Management Agency.

Smoke from the Dragon Bravo fire at Grand Canyon's North Rim area. Credit: M. Quinn (National Park Service)

July 15, 2025

The Weather Forecast Office in Flagstaff created HYSPLIT runs of chlorine gas released from a burning wastewater treatment plant at the Grand Canyon’s North Rim.