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Read the Latest from ARM

Screenshot of the top of the SONDE instrument page, featuring a launch photo, a mentor video, and buttons to access the instrument handbook and browse and cite data

Features

Welcome to the New-Look ARM.gov!

27 February 2025

ARM.gov has gotten a refresh after more than eight years with its previous look. Peruse the site's new features!

Busy at Bankhead

27 February 2025

More instruments are going up at ARM’s newest long-term atmospheric observatory, and science activity is increasing.

Brave New CoURAGE Campaign Set to Begin

2 December 2024

In and around Baltimore, Maryland, scientists, technicians, and students are poised for a year of measuring an urban atmosphere during the Coast-Urban-Rural Atmospheric Gradient Experiment (CoURAGE).

A cropped-in AERINF quicklook image captures a partial time series of the radiance in window channels for AERI Channel 2 (2600 cm-1) on May 23, 2024, during the CAPE-k field campaign. Image is from Krista Gaustad, Pacific Northwest National Laboratory.

Data Announcements

AERI Noise Filtered Data Available for 3 Current ARM Deployments

4 June 2025

The Atmospheric Emitted Radiance Interferometer (AERI) Noise Filtered (AERINF) value-added product is designed to eliminate as much random noise as possible in the AERI's sky spectra.

Leak Affects Cloud Condensation Nuclei Data From 2 ARM Campaigns

2 June 2025

The impacted data are from the TRacking Aerosol Convection interactions ExpeRiment (TRACER) and the Eastern Pacific Cloud Aerosol Precipitation Experiment (EPCAPE).

New Data Products Available for Ongoing ARM Deployments

21 May 2025

ARM has released new disdrometer and sonde value-added products for current mobile deployments in Alabama, Maryland, and Tasmania.

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

Research Highlights

Increasing model spatial resolution fails to reduce simulated storm biases

21 January 2025

Accurately predicting impacts from storms depends on accurately simulating their growth as a function of atmospheric conditions. Using a model setup like those used for operational forecasting, results show that total storm rainfall over a large area is reasonably predicted. However, heavy rain rates were too frequent and light rain rates were too infrequent at a local scale when compared to observations, meaning the balance between rainfall frequency and intensity is incorrectly predicted. This is caused by an excessive number of simulated storms, a model bias that worsens as the atmosphere becomes more stable. Increasing model resolution to better resolve storm circulations does not reduce these biases, indicating model representation of precipitation formation and growth in storms requires improvement.

New methods for extracting more detail from existing data sets

21 January 2025

Detailed data of what is in the atmosphere is often very complex, containing thousands of chemicals without known identities or properties. By developing new automated tools for analyzing certain types of data, this research will substantially improve the ability to make sense of these data and extract new details about the composition of the atmosphere.

Bridging the data gap in Southern Hemisphere aerosol research

17 January 2025

Aerosols are known to affect cloud properties, including their formation, growth, and precipitation, which in turn influences climate over long time scales. Aerosol-cloud-interactions (ACI) depend on how their properties change together, yet few measurements capture this variability, especially in the presence of convective cloud populations that can be observed routinely by satellites. Models are often challenged because they assume aerosols are constant, which potentially leads to erroneous estimates of the impact of ACI. Furthermore, ACI pathways in convective clouds are complex and remain highly uncertain.   To address the data gap and better understand the interactions of convective clouds and the surrounding environment, extensive in situ and remote-sensing measurements were collected during the Cloud, Aerosol, and Complex Terrain Interactions (CACTI) field campaign conducted between October 2018 and April 2019 over the Sierras de Córdoba range of central Argentina. The field campaign aimed to understand how convective clouds interact with environmental conditions, thermodynamics, aerosols, and surface properties. In contrast with previous studies that focused on clouds, this study describes measurements of aerosol number, size, composition, mixing state, and cloud condensation nuclei collected during CACTI.

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Atmospheric Radiation Measurement (ARM) | Reviewed March 2025