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 ATD Division in Oak Ridge, TN uses sUAS to measure how temperature and relative humidity change with altitude, map the temperature and reflectivity characteristics of the Earth’s surface, and perform storm damage assessment in a never-before-available way that is faster, cheaper, and safer than using manned aircraft.

ARL’s Fleet of Aircraft
ARL currently has four sUAS that it flies on a regular basis, including three multi-rotor copters and one fixed-wing aircraft. The primary purpose of two of the multi-rotor aircraft (a DJI S-1000  and a Meteomatics Meteodrone SSE ) is to make measurements of temperature, relative humidity, and winds (Meteodrone only) as a function of altitude above the Earth’s surface. The third multi-rotor (a Microdrone MD4-1000 ) carries a LiDAR (Light Detection And Ranging) system to make high-resolution 3-D measurements of the Earth’s surface. The fixed-wing aircraft, a BlackSwift Technologies S2  has a payload module 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. ARL acquired a second BST S2 with a different payload module to make in-situ measurements of 3-D atmospheric turbulence and flux measurements of CO2 and CH4.

The DJI S-1000 UAS
Meteomatics Meteodrone (left) and BlackSwift Technologies S2 (right).

ARL Uncrewed Aircraft Fleet Capabilities

Model

APH-28

MD4-1000

BlackSwift
S2

Year acquired

2021

2017

2019

Variables Sampled

T, q

T, q

T, q, u, v, w

Manufacturer

Aerial Imaging Solutions

Microdrone

BlackSwift Technologies

Units in Fleet

1

1

2

Vehicle Type

Multi-rotor

Multi-rotor

Fixed-wing

Gross Weight

5 kg

3.85 kg

6.6 kg

Wing Span

1.0 m

1.0 m

3.0 m

Length

1.0 m

1.0 m

2.0 m

Payload Capacity

1.8 kg

1.2 kg

2.3 kg

Engine Type

6 electric motors

4 electric motors

1 electric motor

Autopilot

AVR

Microdrone

SwiftPilot

Max Speed

13m s·1

10m s·1

24.7m s·1

Loiter Speed

0 m s·1

0 m s·1

15 m s·1

Endurance

20 min

25 min

80 min

Ceiling

4270 m

500 m

3000 m

 

The fleet of UAS currently owned by ARL / ATDD.

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 test 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.

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.
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.

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.

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.

Fluxes and Trace Gasses from UAS

ARL is conducting ongoing UAS operations at House Mountain Radio Control (HMRC), located near Corryton, TN about 30 miles northeast of ATDD. The purpose of the UAS operations at HMRC is to evaluate and develop new techniques for obtaining turbulence and flux measurements from both rotary-wing and fixed-wing UAS. Additional efforts are underway to use UAS to sample trace gas species and ultimately to derive fluxes of these quantities.

ARL Papers:

Lee, T. R., M. Buban, E. Dumas, and C. B. Baker, 2017: A new technique to estimate sensible heat fluxes around micrometeorological towers using small unmanned aircraft systems. Journal of Atmospheric and Oceanic Technology, 34 (9), 2103-2112, https://doi.org/10.1175/JTECH-D-17-0065.1.

Ed Dumas of ARL / ATDD flies the BST S2 at HMRC in November 2021.

Quasi-routine UAS flights to support operational weather forecasting needs

In 2020, ARL performed nearly 250 flights with its Meteomatics SSE UAS to sample profiles of temperature, humidity, wind speed, and wind direction at the Oliver Springs Airport, located approximately five miles northwest of the lab. ARL provided these data in near real-time to the local National Weather Service Weather Forecast Office in Morristown, TN to assist with their weather forecast operations.

2020 Ed Dumas operates the Meteomatics UAS at Oliver Springs in September 2020.

Albuquerque International Balloon Fiesta

In October 2019, ARL performed UAS flights with its Meteomatics SSE to obtain vertical profiles of temperature, moisture, wind speed, and wind direction. These data were shared with local forecasters for the Balloon Fiesta, and the data played a vital role in making decisions about whether or not to fly the balloons during the event.

Mark Rogers of NOAA OMAO prepares the Meteomatics SSE for a flight during the Albuquerque International Balloon Fiesta

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.