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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 Conducts Phoenix Study to Unlock Secrets of Monsoon Storms

30 July 2026

A field campaign hosted by Arizona State University will explore how extreme heat, urban growth, and dust influence storm intensity.

Longtime ARM Director Winds Down Impactful Career

20 July 2026

Jim Mather, who is retiring this summer after three decades with ARM, reflects on his life and career.

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.

This cropped MWRRET quicklook image provides information from the Bankhead National Forest supplemental site at Double Springs in northwestern Alabama on July 18, 2025. The image shows retrieved precipitable water vapor from the physical method (blue) and statistical method (green) with sonde launch times noted (purple); and retrieved liquid water path from the physical method (blue) and statistical method (green). The full image is in the data announcement.

Data Announcements

New Microwave Radiometer Retrieval Data Released

3 August 2026

The Microwave Radiometer Retrievals (MWRRET) value-added product is available for the first time for several ARM sites. In addition, the MWRRET data set for ARM’s North Slope of Alaska atmospheric observatory has been extended.

New EPCAPE VARANAL Forcing Data Released to Evaluation

30 July 2026

A new version of continuous large-scale forcing data for the 2023–2024 Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE) is now available from ARM.

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.

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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