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Atmospheric Radiation Measurement (ARM)

The Atmospheric Radiation Measurement (ARM) user facility is a U.S. Department of Energy (DOE) scientific user facility. ARM provides the climate research community with strategically located in situ (i.e. on site) and remote sensing data collected from fixed location, mobile, and aerial observatories. ARM collects, processes, quality-checks, stores, and distributes continuous climate measurements, with many observatories collecting data 24 hours a day.
The ARM user facility is designed to improve the understanding and representation of clouds and aerosols in climate and earth system models, as well as their interactions and coupling with the Earth’s surface. For over 30 years, ARM’s mission has been to advance a robust predictive understanding of Earth’s climate and environmental systems and to inform the development of sustainable solutions to the Nation’s energy and environmental challenges. ARM’s mission is still being executed and continues to strengthen ties between observations and models, including an accelerated application of its data to modeling simulations.

ARM Atmospheric Observatories

Three fixed-location atmospheric observatories represent a broad range of atmospheric conditions. Each observatory is operated by the Atmospheric Radiation Measurement (ARM) user facility and collects large amounts of atmospheric data. Scientists use data collected from these observatories to obtain measurements of radiative fluxes, cloud and aerosol properties, precipitation, and related atmospheric characteristics in diverse climate regimes.

Active Fixed Locations

The Southern Great Plains Observatory

Active Mobile and Aerial Observatories

AMF3 scouting visit in Alabama's Bankhead National Forest. The new deployment will study aerosol, cloud, and land-atmosphere interactions.
ARM Mobile Facilities (AMF)
Three AMF are similar to the fixed-location observatories. However, AMF are deployed for periods of about one year at a time anywhere in the world. The second mobile facility (AMF2) was operated at Gunnison, CO from 1 September 2021 - 15 June 2023 (SAIL) and is transitioning to Tasmania, Australia. The third mobile facility (AMF3) was operated at Oliktok Point, Alaska, from September 2013 to June 2021 and is transitioning to the Southeastern United States.

A Bombardier Challenger 850 regional jet fitted with extensive atmospheric data collection sensors

ARM Aerial Facilities (AAF)
ARM AAF collects airborne measurements during intensive field campaigns or long-term, regularly scheduled flights. AAF collects data with crewed aircraft, uncrewed aerial systems, and tethered balloon systems.

ARM Operations and Infrastructure

The ARM user facility is a multi-laboratory collaboration that is a key contributor to national and international climate research efforts. ARM operates over 450 instruments on aerial platforms and across six ground-based observatories that collects data to improve our understanding of atmospheric processes and advance Earth system models. All data is freely available to the public. ARM Operations and Infrastructure supports the data analysis needs of researchers in DOE’s Atmospheric System Research program and other climate programs. Our activities encourage and facilitate the use of data, estimate uncertainties in climate models, and improve comparison of models with observations.
 ARM’s Data Workbench concept will enable a unified ecosystem for users to access data, computing resources, and software packages to perform complex data analysis using ARM data. (Image credit: Carlos Jones, Oak Ridge National Laboratory)
ARM Data Center
The ARM Data Center provides a robust, integrated data and computing environment to advance understanding of atmospheric radiation. It currently holds more than 3.5 petabytes of data from over 11,000 sources, including data collected from field campaigns, instruments, and shared by principal investigators. The data center offers computing infrastructure to support next-generation atmospheric model simulations, storage for large files, big-data analytics, and machine learning for atmospheric and climate science research.
Diagram for Lawrence Livermore National Laboratory's (LLNL) Atmospheric Radiation Measurement (ARM) Infrastructure Project. (Image credit: Shaocheng Xie of Lawrence Livermore National Laboratory)
ARM Data Products for Modelers
This project supports the data analysis needs of researchers who are creating cloud and climate models in DOE’s Atmospheric System Research program and other climate programs. Our activities encourage and facilitate the use of data, estimate uncertainties in climate models, and improve comparison of models with observations.
ARM instruments deployed with the first ARM Mobile Facility in La Porte, TX as part of the TRACER:  TRacking Aerosol Convection interactions ExpeRiment. (Image credit: Guy Tubbs; courtesy of the Atmospheric Radiation Measurement (ARM) user facility)
ARM Instrument Experts
The Atmospheric Radiation Measurement user facility deploys over 400 instruments across its fixed and mobile facilities. It takes a large (>80) team of instrument experts (what ARM calls Instrument Mentors) across multiple institutions, including national laboratories and universities, to oversee those instruments and ensure that they are producing high-quality data for users of ARM data. Instruments mentors do change from time-to-time so to find the latest information, please visit the ARM mentor list.
A series of containers outfitted with sophisticated ARM sampling equipment will operate from February 2023 to February 2024 in La Jolla, California, as part of the Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE). (Image credit: Karen Steinbock)
ARM Translator Group
The Atmospheric Radiation Measurement user facility is a multi-laboratory collaboration that is a key contributor to national and international climate research efforts. Translators are liaisons between the scientific community and ARM staff. Our work explores radar meteorology, precipitation and cloud radar techniques for estimating rainfall and drop size distributions, and adaptive radar scanning for climate applications.
Tethered balloon system (TBS) flights were launched in September 2021 during ARM’s Surface Atmosphere Integrated Field Laboratory (SAIL) field campaign in Gothic, Colorado. The SAIL campaign, which will run from September 2021 to June 2023, will provide insights into mountainous water-cycle processes. (Image by Brent Peterson, Sandia National Laboratories)
Atmospheric Radiation Measurement (ARM) User Facility
The Atmospheric Radiation Measurement user facility is a multi-laboratory collaboration that is a key contributor to national and international climate research efforts. We operate over 450 instruments across six ground-based observatories that collect data to improve our understanding of atmospheric processes and advance Earth system models. All data is freely available to the public.
Pyranometers (Kipp & Zonen model CM-21 in the foreground and Eppley model PSP) at the Solar Radiation Research Laboratory (SRRL). Golden, Colorado. (Image credit: Thomas Stoffel, NREL)
Broadband and Longwave Radiometer Mentorship for ARM
The Solar Radiation Research Laboratory (SRRL) at the National Renewable Energy Laboratory provides leadership for the ARM Facility’s solar radiation measurements. Using state of the art instrumentation, quality assessments and control methods, the goal is to ensure that the highest-quality solar radiation measurements are continuously available from all ARM deployments.
ARM-Carbon-project
Carbon Research with ARM Data
One of the challenges in carbon cycle research is the vast range of scales, from plant to global atmosphere, which must be bridged by measurements and models. A second major challenge is understanding the strong coupling among the fluxes of carbon, water and energy, and how these link to land use and climate. Spanning the broad range of scales and land uses requires integrating ecosystem processes over heterogeneous surfaces and coupling them with hydrological and meteorological processes. The ARM/LBNL Carbon project aims to study three important aspects of the carbon cycle: fluxes, concentrations (stocks), and processes that control fluxes and stocks.
A rainbow emerged after a summer thunderstorm near the SAIL study area.  The rainbow arcs over to the Taylor Park Reservoir and highlights how a holistic understanding, through atmosphere-through-bedrock studies, of the water that is managed in the Upper Colorado River Basin (UCRB) is directly impacted by how the sunlight and thermal energy warm the surface and created the thunderstorm, leading to precipitation in the atmosphere that impacts the water levels in the Reservoir.  (Image credit: SAIL)
SAIL: Surface Atmosphere Integrated Field Laboratory
The SAIL campaign is a nearly two-year deployment of an Atmospheric Radiation Measurement (ARM) Mobile User facility (AMF2) to understand how the atmosphere impacts water resources in the Colorado River, and why water resources are diminishing so quickly. The ARM mobile facility includes more than four dozen advanced instruments measuring precipitation, clouds, aerosols, winds, radiation, temperature, and humidity to the East River Watershed site near Crested Butte, Colorado. Through SAIL, atmospheric scientists will collaborate with surface and subsurface researchers to investigate watershed hydro-biogeochemical processes and create an atmosphere-through-bedrock integrated field laboratory at the East River.

Modeling with ARM Data

The ICLASS logo shows the scope and scale of the ICLASS project. (Image credit: Jerome Fast)
ICLASS: Integrated Cloud, Land-surface, and Aerosol System Study
The ICLASS vision is to transform our understanding of climate processes and provide more robust model representations of the climate system by integrating new knowledge about clouds and aerosols, and their interactions with each other and the Earth’s surface. This approach combines measurements and data discovery with high-resolution multi-scale modeling to advance the fundamental understanding of processes associated with land-atmosphere-cloud interactions, transitions in cloud populations, the evolution of carbonaceous aerosol populations, and aerosol-cloud interactions.
Low-level clouds observed at the Department of Energy's Atmospheric Radiation Measurement (ARM) sites; the Eastern North Atlantic (ENA) atmospheric observatory and Southern Great Plains (SGP) atmospheric observatory. (Image credit: the Department of Energy Atmospheric System Research project)
Multiscale Models to Advance the Understanding of Liquid-Phase Cloud Response to Aerosol Perturbation Over Ocean and Land with ARM Data
This DOE Early Career Research Program project aims to study the response of clouds composed of liquid water (as opposed to clouds cold enough to form ice-phase clouds) as they change to air-suspended particles (i.e., aerosols) and reduce the related uncertainty in the DOE Earth system model.
Stereo camera ring of three camera pairs at the SGP Central Facility site is shown on the map. The cameras of each pair are separated by ~600 m from each other.  The common field of view of all cameras cover approximately 6 km by 6 km region around the CF. The pictures show frames taken by each camera at the same time on August 31, 2017 at 18:00 UTC. (Image credit: Wyatt Stout)
Stereo Photogrammetry of Clouds at the ARM Sites
This project aims to understand the behavior of warm, moist air using stereophotogrammetry (an estimate of the 3D coordinates of points on an object), instruments at Atmospheric Radiation Measurement sites, and turbulence simulations of observations. Stereo cameras are used to characterize the sizes, speeds, circulations, and ascent distances of individual convective bubbles through their life cycle. These data on cloud life cycles are difficult, if not impossible, to obtain with other ARM instruments.
A schematic diagram illustrating the approaches, science foci, and tools for THREAD (Tying in High Resolution E3SM with ARM Data), an Atmospheric System Research (ASR) Science Focus Area (SFA) project bridging the Department of Energy’s (DOE) Atmospheric Radiation Measurement (ARM) and Energy Exascale Earth System Model (E3SM) programs. THREAD will use ARM observations for diagnosis and improvement of E3SM’s kilometer-scale model configuration known as the Simplified Cloud-Resolving E3SM Atmospheric Model (SCREAM). (Image by Lawrence Berkeley National Laboratory)
THREAD: Tying in High Resolution E3SM with ARM Data
This project harnesses DOE's recent development of the global storm-resolving model and recent advances in ground-based observations using Atmospheric Radiation Measurement (ARM) data to significantly enhance the predictability of the kilometer-scale Energy Exascale Earth System Model (E3SM). This will be accomplished by diagnosing and improving the representations of clouds, precipitation, and land-atmosphere interaction processes.

Science with ARM Data

Tethered Balloon Sonde (TBS) with aerosol instrumentation for vertical profiling deployed in January 2023 at SAIL. (Image credit: Sandia National Laboratory)
Aerosol Regimes and Processes with SAIL Data
This project uses data collected from ground-based instruments and tethered balloon sondes (i.e. tethered weather balloons) in the Colorado East River Watershed Basin to study variability of aerosol processes seasonally. Aerosols are fine solid or liquid particles in a gas and most of the data collected are in situ (in its original place) measurements of different types of aerosols. Our goal is to understand the role of aerosols within mountain hydrology.
ARM instruments deployed with the first ARM Mobile Facility in La Porte, TX as part of the TRACER:  TRacking Aerosol Convection interactions ExpeRiment. (Image credit: Guy Tubbs; courtesy of the Atmospheric Radiation Measurement (ARM) user facility)
ARM Instrument Experts
The Atmospheric Radiation Measurement user facility deploys over 400 instruments across its fixed and mobile facilities. It takes a large (>80) team of instrument experts (what ARM calls Instrument Mentors) across multiple institutions, including national laboratories and universities, to oversee those instruments and ensure that they are producing high-quality data for users of ARM data. Instruments mentors do change from time-to-time so to find the latest information, please visit the ARM mentor list.
A series of containers outfitted with sophisticated ARM sampling equipment will operate from February 2023 to February 2024 in La Jolla, California, as part of the Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE). (Image credit: Karen Steinbock)
ARM Translator Group
The Atmospheric Radiation Measurement user facility is a multi-laboratory collaboration that is a key contributor to national and international climate research efforts. Translators are liaisons between the scientific community and ARM staff. Our work explores radar meteorology, precipitation and cloud radar techniques for estimating rainfall and drop size distributions, and adaptive radar scanning for climate applications.
ARM-Carbon-project
Carbon Research with ARM Data
One of the challenges in carbon cycle research is the vast range of scales, from plant to global atmosphere, which must be bridged by measurements and models. A second major challenge is understanding the strong coupling among the fluxes of carbon, water and energy, and how these link to land use and climate. Spanning the broad range of scales and land uses requires integrating ecosystem processes over heterogeneous surfaces and coupling them with hydrological and meteorological processes. The ARM/LBNL Carbon project aims to study three important aspects of the carbon cycle: fluxes, concentrations (stocks), and processes that control fluxes and stocks.
Low-level clouds observed at the Department of Energy's Atmospheric Radiation Measurement (ARM) sites; the Eastern North Atlantic (ENA) atmospheric observatory and Southern Great Plains (SGP) atmospheric observatory. (Image credit: the Department of Energy Atmospheric System Research project)
Multiscale Models to Advance the Understanding of Liquid-Phase Cloud Response to Aerosol Perturbation Over Ocean and Land with ARM Data
This DOE Early Career Research Program project aims to study the response of clouds composed of liquid water (as opposed to clouds cold enough to form ice-phase clouds) as they change to air-suspended particles (i.e., aerosols) and reduce the related uncertainty in the DOE Earth system model.
Field site and field crew (Image credit: Oak Ridge National Laboratory)
NGEE Arctic: Next Generation Ecosystem Experiments - Arctic
The Next-Generation Ecosystem Experiments seeks to improve our predictive understanding of carbon-rich Arctic system processes and feedbacks to climate. We do this through experiments, observations, and synthesis of existing datasets that strategically inform models and enhance the knowledge base required to initialize, calibrate, and evaluate models.
A rainbow emerged after a summer thunderstorm near the SAIL study area.  The rainbow arcs over to the Taylor Park Reservoir and highlights how a holistic understanding, through atmosphere-through-bedrock studies, of the water that is managed in the Upper Colorado River Basin (UCRB) is directly impacted by how the sunlight and thermal energy warm the surface and created the thunderstorm, leading to precipitation in the atmosphere that impacts the water levels in the Reservoir.  (Image credit: SAIL)
SAIL: Surface Atmosphere Integrated Field Laboratory
The SAIL campaign is a nearly two-year deployment of an Atmospheric Radiation Measurement (ARM) Mobile User facility (AMF2) to understand how the atmosphere impacts water resources in the Colorado River, and why water resources are diminishing so quickly. The ARM mobile facility includes more than four dozen advanced instruments measuring precipitation, clouds, aerosols, winds, radiation, temperature, and humidity to the East River Watershed site near Crested Butte, Colorado. Through SAIL, atmospheric scientists will collaborate with surface and subsurface researchers to investigate watershed hydro-biogeochemical processes and create an atmosphere-through-bedrock integrated field laboratory at the East River.
A schematic diagram illustrating the approaches, science foci, and tools for THREAD (Tying in High Resolution E3SM with ARM Data), an Atmospheric System Research (ASR) Science Focus Area (SFA) project bridging the Department of Energy’s (DOE) Atmospheric Radiation Measurement (ARM) and Energy Exascale Earth System Model (E3SM) programs. THREAD will use ARM observations for diagnosis and improvement of E3SM’s kilometer-scale model configuration known as the Simplified Cloud-Resolving E3SM Atmospheric Model (SCREAM). (Image by Lawrence Berkeley National Laboratory)
THREAD: Tying in High Resolution E3SM with ARM Data
This project harnesses DOE's recent development of the global storm-resolving model and recent advances in ground-based observations using Atmospheric Radiation Measurement (ARM) data to significantly enhance the predictability of the kilometer-scale Energy Exascale Earth System Model (E3SM). This will be accomplished by diagnosing and improving the representations of clouds, precipitation, and land-atmosphere interaction processes.