Measurement of boundary layer ozone concentrations on-board a Skywalker unmanned aerial vehicle

This paper describes the components and usage of an unmanned aerial vehicle developed for measuring turbulence in the atmospheric boundary layer. A method of computing the time-dependent wind speed from a moving velocity sensor data is provided. The physical system built to implement this method using a five-hole probe velocity sensor is described along with the approach used to combine data from the different on-board sensors to allow for extraction of the wind speed as a function of time and position. The approach is demonstrated using data from three flights of two unmanned aerial vehicles (UAVs) measuring the lower atmospheric boundary layer during transition from a stable to convective state. Several quantities are presented and show the potential for extracting a range of atmospheric boundary layer statistics.

Download Full-text

Weight assessment for a blended wing Body-Unmanned aerial vehicle implementing boundary layer ingestion

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/383/1/012068 ◽

2018 ◽

Vol 383 ◽

pp. 012068 ◽

Cited By ~ 3

Author(s):

E A Valencia ◽

V H Alulema ◽

V H Hidalgo

Keyword(s):

Boundary Layer ◽

Unmanned Aerial Vehicle ◽

Aerial Vehicle ◽

Blended Wing Body

Download Full-text

A Lightweight Observation System for Atmospheric Carbon Dioxide Concentration Using a Small Unmanned Aerial Vehicle

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech1866.1 ◽

2006 ◽

Vol 23 (5) ◽

pp. 700-710 ◽

Cited By ~ 34

Author(s):

T. Watai ◽

T. Machida ◽

N. Ishizaki ◽

G. Inoue

Keyword(s):

Boundary Layer ◽

Planetary Boundary Layer ◽

Unmanned Aerial Vehicle ◽

Atmospheric Carbon Dioxide ◽

Carbon Dioxide Concentration ◽

Ground Surface ◽

Atmospheric Co2 ◽

Observation System ◽

Aerial Vehicle ◽

A Site

Abstract To make the investigation of the temporal and spatial variations of atmospheric CO2 in and above the planetary boundary layer more flexible and economical, a lightweight observation system using a small unmanned aerial vehicle has been developed whose flight path is preset using GPS. The total weight of the CO2 measurement device carried inside the vehicle is about 3.5 kg. The device is equipped with both flow and pressure controllers and can be used to measure atmospheric CO2 from the ground surface to a maximum altitude of about 3000 m. The response time of the instrument is about 20 s, with a precision of about ±0.26 ppm. The observation system is easy to handle and can be easily and quickly deployed at a site to make frequent measurements in and above the boundary layer. Compared to the deployment of a piloted aircraft the system shows distinctive advantages, in addition to being more affordable. To test the system, preliminary measurements over a boreal forest area in Japan in the summer of 2000 have been conducted. The results indicate that the unmanned aerial vehicle measurement system provides an affordable platform that can be used to obtain quantitative understanding of the temporal and vertical variations of atmospheric CO2 in and above the planetary boundary layer.

Download Full-text

Measurement of turbulent water vapor fluxes using a lightweight unmanned aerial vehicle system

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-4-5529-2011 ◽

2011 ◽

Vol 4 (4) ◽

pp. 5529-5568 ◽

Cited By ~ 2

Author(s):

R. M. Thomas ◽

K. Lehmann ◽

H. Nguyen ◽

D. L. Jackson ◽

D. Wolfe ◽

...

Keyword(s):

Boundary Layer ◽

Water Vapor ◽

Unmanned Aerial Vehicle ◽

System Development ◽

Spatial Scales ◽

Ground Level ◽

Heat Fluxes ◽

Data Logging ◽

Pass Filter ◽

Aerial Vehicle

Abstract. We present here the first application of a lightweight unmanned aerial vehicle (UAV) system designed to measure turbulent properties and vertical latent heat fluxes (λE). Such measurements are crucial to improve our understanding of linkages between surface moisture supply and boundary layer clouds and phenomena such as atmospheric rivers. The application of UAVs allows for measurements on spatial scales complimentary to satellite, aircraft, and tower derived fluxes. Key system components are: a turbulent gust probe; a fast response water vapor sensor; an inertial navigation system (INS) coupled to global positioning system (GPS); and a 100 Hz data logging system. We present measurements made in the continental boundary layer at the National Aeronautics and Space Administration (NASA) Dryden Research Flight Facility located in the Mojave Desert. Two flights consisting of several horizontal straight flux run legs up to ten kilometers in length and between 330 and 930 m above ground level (m a.g.l.) are compared to measurement from a surface tower. Surface measured λE ranged from −53 W m−2 to 41 W m−2, and the application of a Butterworth High Pass Filter (HPF) to the datasets improved agreement to within ± 12 W m−2 for 86 % of flux runs, by removing improperly sampled low frequency flux contributions. This result, along with power and co-spectral comparisons and consideration of the differing spatial scales indicates the system is able to resolve vertical fluxes for the measurement conditions encountered. Challenges remain, and the outcome of these measurements will be used to inform future sampling strategies and further system development.

Download Full-text

Estimation of Sensible Heat Flux and Atmospheric Boundary Layer Height Using an Unmanned Aerial Vehicle

Atmosphere ◽

10.3390/atmos10070363 ◽

2019 ◽

Vol 10 (7) ◽

pp. 363 ◽

Cited By ~ 6

Author(s):

Min-Seong Kim ◽

Byung Hyuk Kwon

Keyword(s):

Boundary Layer ◽

Heat Flux ◽

Wind Speed ◽

Atmospheric Boundary Layer ◽

Unmanned Aerial Vehicle ◽

Sensible Heat Flux ◽

Eddy Correlation ◽

Sensible Heat ◽

Aerial Vehicle ◽

Transfer Method

In this work, sensible heat flux estimated using a bulk transfer method was validated with a three-dimensional ultrasonic anemometer or surface layer scintillometer at various sites. Results indicate that it remains challenging to obtain temperature and wind speed at an appropriate reference height. To overcome this, alternative observations using an unmanned aerial vehicle (UAV) were considered. UAV-based wind speed and sensible heat flux were indirectly estimated and atmospheric boundary layer (ABL) height was then derived using the sensible heat flux data. UAV-observed air temperature was measured by attaching a temperature sensor 40 cm above the rotary-wing of the UAV, and UAV-based wind speed was estimated using attitude data (pitch, roll, and yaw angles) recorded using the UAV’s inertial measurement unit. UAV-based wind speed was close to the automatic weather system-observed wind speed, within an error range of approximately 10%. UAV-based sensible heat flux estimated from the bulk transfer method corresponded with sensible heat flux determined using the eddy correlation method, within an error of approximately 20%. A linear relationship was observed between the normalized UAV-based sensible heat flux and radiosonde-based normalized ABL height.

Download Full-text

Vertical Profiles of Atmospheric Species Concentrations and Nighttime Boundary Layer Structure in the Dry Season over an Urban Environment in Central Amazon Collected by an Unmanned Aerial Vehicle

Atmosphere ◽

10.3390/atmos11121371 ◽

2020 ◽

Vol 11 (12) ◽

pp. 1371

Author(s):

Patrícia Guimarães ◽

Jianhuai Ye ◽

Carla Batista ◽

Rafael Barbosa ◽

Igor Ribeiro ◽

...

Keyword(s):

Boundary Layer ◽

Carbon Monoxide ◽

Unmanned Aerial Vehicle ◽

Layer Structure ◽

Dry Season ◽

Vertical Profiles ◽

Central Amazon ◽

Temperature And Humidity ◽

Aerial Vehicle ◽

Pm2.5 And Pm10

Nighttime vertical profiles of ozone, PM2.5 and PM10 particulate matter, carbon monoxide, temperature, and humidity were collected by a copter-type unmanned aerial vehicle (UAV) over the city of Manaus, Brazil, in central Amazon during the dry season of 2018. The vertical profiles were analyzed to understand the structure of the urban nighttime boundary layer (NBL) and pollution within it. The ozone concentration, temperature, and humidity had an inflection between 225 and 350 m on most nights, representing the top of the urban NBL. The profile of carbon monoxide concentration correlated well with the local evening vehicular congestion of a modern transportation fleet, providing insight into the surface-atmosphere dynamics. In contrast, events of elevated PM2.5 and PM10 concentrations were not explained well by local urban emissions, but rather by back trajectories that intersected regional biomass burning. These results highlight the potential of the emerging technologies of sensor payloads on UAVs to provide new constraints and insights for understanding the pollution dynamics in nighttime boundary layers in urban regions.

Download Full-text

Vertical Characteristics of Winter Ozone Distribution within the Boundary Layer in Shanghai Based on Hexacopter Unmanned Aerial Vehicle Platform

Sustainability ◽

10.3390/su11247026 ◽

2019 ◽

Vol 11 (24) ◽

pp. 7026 ◽

Cited By ~ 5

Author(s):

Qian Chen ◽

Dongsheng Wang ◽

Xiaobing Li ◽

Bai Li ◽

Ruifeng Song ◽

...

Keyword(s):

Boundary Layer ◽

Unmanned Aerial Vehicle ◽

Field Experiments ◽

Surface Ozone ◽

Air Pollutant ◽

Ozone Level ◽

Systematic Classification ◽

Ozone Distribution ◽

Aerial Vehicle ◽

Vertical Ozone

Ozone is an important secondary air pollutant and plays different significant roles in regulating the formation of secondary organic aerosols. However, the characteristics of winter vertical ozone distributions have rarely been studied. In the winter of 2017, field experiments were performed in Shanghai, China using hexacopter unmanned aerial vehicle (UAV) platforms. The vertical profiles of ozone were obtained from 0–1200 m above the ground level. Results show that the UAV observations were reliable to capture the vertical variations of ozone. Vertical ozone profiles in the winter are classified into four categories: (1) well-mixed profile, (2) altitudinal increasing profile, (3) stratification profile, and (4) spike profile. Results show that although the average surface ozone level was relatively low, strong ozone variability and high ozone concentrations occurred at the upper air. The maximum observed ozone concentration was 220 ppb. In addition, using meteorological profiles and backward trajectories, we found that the ozone elevation aloft can be attributed to the downward transport of air flow from higher altitudes. Furthermore, ozone accumulation in the winter could be influenced by the horizontal transport of air masses for the northern part of China. This study successfully used hexacopter UAV platforms to perform vertical observations within the boundary layer. This provides systematic classification of winter ozone distribution within the boundary layer.

Download Full-text

Vertical Profiles of Ozone Concentration Collected by an Unmanned Aerial Vehicle and the Mixing of the Nighttime Boundary Layer over an Amazonian Urban Area

Atmosphere ◽

10.3390/atmos10100599 ◽

2019 ◽

Vol 10 (10) ◽

pp. 599 ◽

Cited By ~ 7

Author(s):

Guimarães ◽

Ye ◽

Batista ◽

Barbosa ◽

Ribeiro ◽

...

Keyword(s):

Boundary Layer ◽

Urban Area ◽

Unmanned Aerial Vehicle ◽

Ozone Concentration ◽

Potential Temperature ◽

Specific Humidity ◽

Vertical Profiles ◽

Wet Season ◽

Aerial Vehicle ◽

Median Height

The nighttime boundary layer was studied in an urban area surrounded by tropical forest by use of a copter-type unmanned aerial vehicle (UAV) in central Amazonia during the wet season. Fifty-seven vertical profiles of ozone concentration, potential temperature, and specific humidity were collected from surface to 500 m above ground level (a.g.l.) at high vertical and temporal resolutions by use of embedded sensors on the UAV. Abrupt changes in ozone concentration with altitude served as a proxy of nighttime boundary layer (NBL) height for the case of a normal, undisturbed, stratified nighttime atmosphere, corresponding to 40% of the cases. The median height of the boundary layer was 300 m. A turbulent mixing NBL constituted 28% of the profiles, while the median height of the boundary layer was 290 m. The remaining 32% of profiles corresponded to complex atmospheres without clear boundary layer heights. The occurrence of the three different cases correlated well with relative cloud cover. The results show that the standard nighttime model widely implemented in chemical transport models holds just 40% of the time, suggesting new challenges in modeling of regional nighttime chemistry. The boundary layer heights were also somewhat higher than observed previously over forested and pasture areas in Amazonia, indicating the important effect of the urban heat island.

Download Full-text