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The U.S. Department of Energy’s Atmospheric Radiation Measurement (ARM) User Facility provides 30-plus years of atmospheric measurements, including data sets from all seven continents and five oceans, to advance the understanding of the Earth’s atmosphere.

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Read the Latest from ARM

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Features

ARM Names New Director

13 July 2026

Atmospheric scientist Larry Berg will guide ARM into the next era of scientific observations and succeed Jim Mather, who has led ARM since 2007.

Streamlining ARM Data Access With AI-Ready Infrastructure

28 May 2026

New storage, software, and computing frameworks set the stage for next-generation data tools and research support.

Capturing Coastal Cloud Complexity

28 May 2026

More than two years after ending operations in La Jolla, California, the Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE) is producing journal articles and cases for model evaluation. 

A data plot shows two lines, which each illustrate data from a variational analysis domain. One of the domains has a radius of 75 kilometers, and the other has a radius of 150 kilometers.

Data Announcements

New Southern Great Plains Continuous Large-Scale Forcing Data Released

13 July 2026

This constrained variational analysis (VARANAL) value-added product includes both the large-scale forcing terms and the evaluation fields, which can be used for driving a variety of models and validating simulations.

ARM Releases New Cloud Optical Depth Product

8 July 2026

ARM has developed the Three-Channel Sunphotometer Cloud Mode (SPHOTCOD) value-added product to provide information on cloud properties for process studies.

First Characterized and Corrected BNF Radar Data Now Available

6 July 2026

The new data are available from four radars at the Bankhead National Forest (BNF) atmospheric observatory in northern Alabama.

Clouds roll across the sky over the Kennaook/Cape Grim area.

Research Highlights

Turbulence Controls on Marine Shallow Cumulus Cloudiness

18 June 2026

Marine shallow cumulus clouds cool the Earth by reflecting solar radiation back to space and are challenging to accurately represent in earth system models. These clouds are intimately coupled with turbulence in the boundary layer. Here, vertical air motion and its co-variability with cumulus cloudiness are characterized using data from the Atmospheric Radiation Measurement (ARM) Eastern North Atlantic (ENA) observatory.

Generating a Stratocumulus-Like Cloud Top in a Convection-Cloud Chamber

1 June 2026

Stratocumulus clouds cover a large fraction of Earth’s surface and strongly influence regional weather and the global energy balance. Entrainment, the mixing process at the top of the stratocumulus-topped boundary layer, strongly influences cloud lifetime, precipitation, and radiative properties. Despite its importance, entrainment remains poorly understood, largely due to the difficulty in observing fine-scale structures near the cloud top, which can be only meters thick. We therefore propose a laboratory facility with controllable conditions and the use of numerical simulations to demonstrate how cloud-top entrainment can be studied experimentally.

A Concept of a Convection-Cloud Chamber to Study Aerosol-Cloud-Drizzle Interactions

22 May 2026

The Aerosol-Cloud-Drizzle Convection Chamber (ACDC2) collaboration has developed a comprehensive concept and modeling hierarchy for a convection-cloud chamber facility designed to investigate the chain of events from aerosol activation to cloud droplet growth and drizzle formation within turbulent clouds. The proposed 9-meter-tall chamber enables steady-state turbulence and microphysical conditions, facilitating continuous direct observation of cloud and aerosol properties.

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Atmospheric Radiation Measurement (ARM) | Reviewed March 2025