Uncrewed Aircraft to Measure the Boundary Layer

The advent of small, uncrewed aircraft systems (sUAS) for atmospheric research offers opportunities to make unique meteorological measurements in the lowest layer of the Earth’s atmosphere. ARL’s Atmospheric Transport and Dispersion Division in Oak Ridge, TN uses sUAS to measure how temperature, humidity and wind change with altitude and map the temperature and reflectivity characteristics of the Earth’s surface.

ARL’s Fleet of Aircraft
ARL currently has four sUAS, including two multi-rotor copters and two fixed-wing aircraft. The primary purpose of two of the multi-rotor aircraft (i.e., the CopterSonde and APH-28) is to make measurements of temperature, relative humidity, and winds. The fixed-wing aircraft are both BlackSwift Technologies S2’s and have payload modules to make images of the Earth’s surface in multiple wavelengths to look at incoming and reflected solar radiation, as well as to measure in-situ air temperature and relative humidity.

Field Studies

Locations where ARL / ATDD has conducted UAS field measurements.

Since 2015, ATDD has conducted nearly 750 UAS flights during short-term field campaigns across the US and to help support forecasting decisions at the local National Weather Service (NWS) Weather Forecast Office (WFO) in Morristown, TN. More details about these deployments are found below.

In order to evaluate emerging technologies that will ultimately allow for sUASs to be operated beyond visual line-of-sight, the BST S2 and the Meteomatics Meteodrone SSE were tested during an experiment at the Avon Park Air Force Range in Avon Park, Florida in March, 2019. The purpose of this experiment was to evaluate technologies such as solid-state radar systems and real-time air traffic display systems while simultaneously flying several sUAS to altitudes of 1 km and above. These systems will ultimately allow sUASs to be operated safely in the National Airspace System beyond visual line-of-sight, which is critical to fulfill weather forecasting needs of the future. More details about the Avon Park experiment are available on the ARL News page and also in a NOAA Technical Memorandum

ARL continues to expand its arsenal of sUAS platforms and instrumentation and explore options to fly to higher altitudes than ever before. ARL is now operating its sUAS up to 1 km altitude at the Oliver Springs Airport, located approximately five miles north of the lab, and to provide this information in near real-time to the local National Weather Service Weather Forecast Office in Morristown to assist with their weather forecast operations.

CHEESEHEAD (Chequamegon Heterogeneous Ecosystem Energy-balance Study Enabled by a High-density Extensive Array of Detectors)

In summer and fall of 2019, ARL participated  in the Chequamegon Heterogeneous Ecosystem Energy-balance Study Enabled by a High-density Extensive Array of Detectors 2019 (CHEESEHEAD 2019) study near Park Falls, WI with collaborators from the University of Wisconsin and other NOAA laboratories. The purpose of CHEESEHEAD is improved understanding of how plants affect the weather on a local scale. Acquiring this understanding requires making many measurements of temperature, moisture, and wind within and above the forest canopy which ARL’s sUAS will be critical component.  ARL operated its Meteomatics SSE to sample low-level temperature, moisture, and wind fields, as well as its MD4-1000 sUAS outfitted with a downward-pointing lidar to capture fine-scale changes in surface roughness for three campaigns. Following CHEESEHEAD, ARL performed sUAS flights with its Meteomatics SSE and BST S2 during the Albuquerque International Balloon Fiesta to assist with weather forecasting operations during the event.

Goal: Investigate the role of surface heterogeneity on boundary layer development and heat and water exchanges processes

Data Archive: https://www.eol.ucar.edu/field_projects/cheesehead

Study Period: July – October 2019

Location: 10 km x 10 km domain around the WLEF TV tower (447 m) near Park Falls, WI 

Collaborators: University of Wisconsin, NOAA, NCAR, NEON, and many other university participants both national and international

ARL Papers:

Butterworth, B. J., A. Desai, S. Metzger, P. A. Townsend; M. D. Schwartz; G. W. Petty; M. Mauder, H. Vogelmann, C. G. Andresen, T. J. Augustine, T. H. Bertram, W. O.J. Brown, M. Buban, P. Cleary, D. J. Durden, C. R. Florian, E. Ruiz Guzman, T. J. Iglinski, E. L. Kruger, K. Lantz, T. R. Lee, T. P. Meyers, J. K. Mineau, E. R. Olson, S. P. Oncley, S. Paleri, R. A. Pertzborn, C. Pettersen, D. M. Plummer, L. Riihimaki, J. Sedlar, E. N. Smith, J. Speidel, P. C. Stoy, M. Sühring, J. E. Thom, D. D. Turner, M. P. Vermeuel, T. J. Wagner, Z. Wang, L. Wanner, L. D. White, J. M. M. Wilczak, D. B. Wright, and T. Zheng, 2020: Connecting Land-Atmosphere Interactions to Surface Heterogeneity in CHEESEHEAD19. Bulletin of the American Meteorological Society, 102, E421-E445, https://doi.org/10.1175/BAMS-D-19-0346.1.

Small drone lifting off the ground in a small clearing at the edge of woods. A man stands a few feet behind it using the control box.
Ed Dumas begins a flight with one of ARL's rotary-wing aircraft.

LAFE (Land-Atmosphere Feedback Experiment)

ARL participated in the Land-Atmosphere Feedback Experiment (LAFE) in the summer of 2017 at the Department of Energy’s Atmospheric Radiation Monitoring (DOE ARM) site near Lamont, Oklahoma. The DJI S-1000 and the Microdrone MD4-1000 both measured temperature and humidity in the lowest 300 meters of the atmosphere and were used to map the Earth’s skin temperature during three intensive observation periods (14 August, 15 August, and 17 August 2017). A NOAA Tech Memo from the 2017 LAFE field campaign is available here .Goal: Investigate land-atmosphere interactions and feedbacks at high spatial resolution in the Southern Great Plains region

Study Period: August 2017

Location: Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site in Northern Oklahoma, USA

Collaborators: NOAA, University of Hohenheim, NCAR, CIMSS, and several other universities. 

LAFE description and data sets

ARL Papers:

Lee, T. R., and M. Buban, 2020: Evaluation of Monin-Obukhov and bulk Richardson parameterizations for surface-atmosphere exchange. Journal of Applied Meteorology and Climatology, 59 (6), 1091-1107, https://doi.org/10.1175/JAMC-D-19-0057.1.

Lee, T. R., M. S. Buban, and T. P. Meyers, 2021: Application of bulk Richardson parameterizations of surface fluxes to heterogeneous land surfaces. Monthly Weather Review, 149, 3243-3264, https://doi.org/10.1175/MWR-D-21-0047.1.

Wulfmeyer V., D. D. Turner, B. Baker, R. Banta, A. Behrendt, T. Bonin, W. A. Brewer, M. Buban, A. Choukulkar, E. Dumas, R. M. Hardesty, T. Heus, D. Lange, T. R. Lee, S. Metzendorf, T. Meyers, R. Newsom, M. Osman, S. Raasch, J. Santanello, C. Senff, F. Späth, T. Wagner, and T. Weckwerth, 2018: A new research approach for observing and characterizing land-atmosphere feedback. Bulletin of the American Meteorological Society, 99 (8), 1639-1667, https://doi.org/10.1175/BAMS-D-17-0009.1.

Dumas, Edward J. (Edward James); Lee, Temple R.; Buban, Michael Scott, 1978-; Baker, Clifford Bruce, 1930-. Small Unmanned Aircraft System (sUAS) measurements during the 2017 Land-Atmosphere Feedback Experiment (LAFE). doi:10.7289/V5/TM-OAR-ARL-277

Ed Dumas of ARL / ATDD prepares the DJI S-1000 for a flight during CHEESEHEAD in July 2019.

2017 Great American Eclipse 

During the Great American Eclipse on 21 August 2017, ARL deployed its DJI S-1000  near Ten Mile, TN, located about 50 miles southwest of Knoxville. The purpose of this study was to better understand the response of the land surface and lower atmosphere to the effects of eclipse totality, which was 2 min 38 sec at this site. The team performed eight flights within a 2.5 hour window of totality and noted marked changes in near-surface temperature and moisture fields that were detectable until one hour after totality. 

ARL Papers:

Buban, M. S., T. R. Lee, E. J. Dumas, C. B. Baker, and M. Heuer, 2019: Observations of the effects of a total solar eclipse on surface and atmospheric boundary layer evolution. Boundary-Layer Meteorology, 171, 257-270, https://doi.org/10.1007/s10546-018-00421-4.

Lee, T. R., M. Buban, M. A. Palecki, R. D. Leeper, H. J. Diamond, E. Dumas, T. P. Meyers, and C. B. Baker, 2018: Great American Eclipse data may fine-tune weather forecasts. Eos, 99 (11), 19-22. 

View from Ten Mile, TN at around 2:25 PM local time on 21 August 2017, approximately 5 min before eclipse totality.

VORTEX-SE (Verification of the Origins of Rotation in Tornadoes Experiment-Southeast)

ARL used the DJI S-1000 (Octocopter) and the Microdrone MD4-1000 to support research to study the formation of severe thunderstorms and tornadoes over Northern Alabama in the spring of 2016 and spring of 2017. The Verifications of the Origins of Rotation in Tornadoes Experiment Southeast (VORTEX-SE) experiment used a large suite of instruments to probe the Earth’s boundary layer both remotely and in-situ. Data from the S-1000  was combined with data from flux towers, microwave radiometers, Doppler radar and LiDAR systems, as well as radiosonde balloons and space-based remote sensing measurements to help form a more complete picture of how the boundary layer changes prior to the onset of severe thunderstorms and tornadoes. The S-1000 was also used to document areas of damage from a tornado that struck near Hartselle, Alabama on 31 March, 2016. NOAA Technical Memos from the 2016 and 2017 VORTEX-SE field campaigns are available here (2016) and here (2017) .

Goal: Understand how fine-scale environmental factors characteristic of the Southeast US affect the formation, intensity, structure, and path of tornadoes in this region

Study Period: Spring 2016 and spring 2017

Location: Alabama

Collaborators: NOAA, NCAR, NASA, CIMMS (now CIWRO), and many other university participants

Campaign Documentation and Data Archive

ARL Papers:

Lee, T. R., M. Buban, D. D. Turner, T. P. Meyers, and C. B. Baker, 2019: Evaluation of the High-Resolution Rapid Refresh (HRRR) model using near-surface meteorological and flux observations from Northern Alabama. Weather and Forecasting, 34 (3), 635-663, https://doi.org/10.1175/WAF-D-18-0184.1.

Markowski, P. M., N. T. Lis, D. D. Turner, T. R. Lee, and M. S. Buban, 2019: Observations of near-surface vertical wind profiles and vertical momentum fluxes from VORTEX-Southeast 2017: Comparisons to Monin-Obukhov similarity theory. Monthly Weather Review, 147 (10), 3811-3824, https://doi.org/10.1175/MWR-D-19-0091.1.

Dumas, Edward J. (Edward James); Lee, Temple R.; Buban, Michael Scott, 1978-; Baker, Clifford Bruce, 1930-. Small Unmanned Aircraft System (sUAS) measurements during the 2017 Verifications of the Origins of Rotation in Tornadoes Experiment Southeast (VORTEX-SE). doi:10.7289/V5/TM-OAR-ARL-274

NOAA / ARL and Mark Rogers (right) of NOAA / OMAO operate the DJI S-1000 near Cullman, AL during a VORTEX-SE intensive observation period in April 2017.