Busy at Bankhead

Published: 27 February 2025

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

A shot looking up at the 140-foot tower with clouds floating above and tree leaves and branches seen in the bottom corners of the photo — This 140-foot (42.7-meter) tower was recently erected as part of ARM’s Bankhead National Forest (BNF) atmospheric observatory in Alabama. Photo is by Mark Spychala, Argonne National Laboratory.

Since October 2024, the Atmospheric Radiation Measurement (ARM) User Facility has provided data from its Bankhead National Forest (BNF) atmospheric observatory in northern Alabama. Data from new BNF sites and instruments will soon be on the way.

With support from the U.S. Forest Service, which is hosting the BNF, ARM has erected a 140-foot (42.7-meter) tower near the observatory’s main site. Instruments on the tower will sample a variety of properties below, within, and above the forest canopy.

Several instruments are now up on the tower, including multi-level meteorological instrumentation, infrared thermometers, and photosynthetically active radiation sensors. Inlets for some trace gas monitoring and flux measurement systems are also up on the tower. However, the instruments are not yet connected to data communications systems. Meanwhile, infrastructure is being installed for other instruments that will go on the tower.

Final site data system installation for the tower is expected by early March 2025, says BNF Site Technical Operations Specialist Mark Spychala.

Two under-canopy towers near the main site have been assembled, with several instruments installed. Spychala says they will be raised up after the placement of infrared thermometers on the towers is finalized.

Outside the forest, Ka- and X-band scanning ARM cloud radars are currently providing data, while evaluation of data from the second-generation C-Band Scanning ARM Precipitation Radar (CSAPR2) is underway. Data from the CSAPR2 are expected to be available soon.

ARM is also operating three supplemental sites outside the forest, with data available on surface fluxes and thermodynamic and wind profiles.

Browse all available BNF data in the ARM Data Center.

Building Scientific Interest and Collaborations

In this video, BNF Site Science Team Lead Chongai Kuang of Brookhaven National Laboratory in New York explains the purpose of the BNF deployment, which is planned to run at least five years.

As more instruments pop up around the BNF, science action is ramping up there.

On December 4 and 5, 2024, ARM hosted a BNF site kickoff meeting at the University of Alabama in Huntsville. A total of 139 people registered to attend in person and online. In addition, 55 people registered for a BNF site tour held on the afternoon of December 5.

The kickoff meeting drew government officials, ARM leaders, researchers, and other parties wanting to know more about the BNF. Attendees learned about ARM and BNF resources for the scientific community, opportunities for science and collaboration with local partners, and how to get started and work with ARM.

Video recordings from Day One and Day Two of the meeting are available on YouTube.

BNF-themed breakout sessions will be part of the 2025 Joint ARM User Facility/Atmospheric System Research (ASR) Principal Investigators Meeting from March 3 to 6 in Rockville, Maryland, and online. These sessions will focus on:

couplings between volatile organic compounds, organic aerosols, and clouds
community organization, planning, and coordination of intensive operational periods
collecting input for a planned BNF scenario as part of the Large-Eddy Simulation (LES) ARM Symbiotic Simulation and Observation (LASSO) activity, which combines high-resolution model output and ARM observations to provide highly detailed descriptions of the atmosphere around ARM sites.

More information is available in the breakout session descriptions.

Aerial Updates

A tethered balloon system hangar sits in a gravel area surrounded by trees. The roof and bed of a gray pickup truck are visible in the bottom left corner of the photo. — The tethered balloon system hangar is ready for BNF flights. Photo is by Patty Campbell, Argonne.

The BNF will see a flurry of aerial activity in March and April 2025.

Flights of the ArcticShark uncrewed aerial system are planned to occur along with the first round of tethered balloon system (TBS) flights at the BNF.

From March 3 to 24, the ArcticShark is scheduled to collect aerosol and meteorological measurements over and around the BNF.

Data from the ArcticShark’s BNF flights in July and August 2024 are freely available through the ARM Data Center.

Currently, ARM has a call open for scientists to deploy the ArcticShark in the BNF region in June and/or August 2025. Letters of intent are due March 7, and abbreviated proposals are due March 21.

TBS flights are planned from March 19 to April 4 and April 9 to 28. Other BNF TBS flights in fiscal year 2025 are slated for June and August.

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ARM is a DOE Office of Science user facility operated by nine DOE national laboratories.