Atmospheric, Climate,
and Earth Sciences Division
Atmospheric, Climate,
and Earth Sciences Division
Land-Atmosphere Interactions
The atmosphere and land surface of the Earth are deeply connected. The two systems constantly exchange energy and matter. These interactions occur on a wide range of scales in both space and time, which makes them challenging to study and model.
Topography, land cover, and land use significantly affect atmospheric phenomena. For example, agricultural activities can churn up soil particles that affect cloud behavior. The type of land cover determines how much energy the Earth absorbs and reflects, changing how the lower atmosphere heats. This further affects atmospheric turbulence, clouds, and precipitation processes.
The soil acts as a major repository of carbon and water. However, they do not permanently stay in the soil. The atmosphere and soil constantly exchange water, greenhouse gases, and aerosols, which has implications for atmospheric greenhouse gas levels, atmospheric humidity, and precipitation. As water evaporates from the soil or is emitted by plants, with their roots extended far into the soil, it enters the atmosphere and increases local humidity. The amount water vapor in the atmosphere significantly influences the weather and climate within a given region.
Modeling land-atmosphere interactions is a key element of rigorously modeling the Earth system. Because land surface processes evolve more slowly than atmospheric processes, accurately representing land-atmosphere interactions in regional and global models may improve weather and climate predictions.
The wide range of interactions between the land surface and atmosphere makes the field highly interdisciplinary. It crosses a diverse range of specialties, often requiring collaboration between soil, plant, and atmospheric scientists. PNNL’s cross-disciplinary approach, modeling expertise, and participation in field campaigns enable important contributions to understanding land-atmosphere interactions.