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Abstract. Ozone is a pollutant formed in the atmosphere by photochemical processes involving nitrogen oxides (NOx) and volatile organic compounds (VOCs) when exposed to sunlight. Tropospheric boundary layer ozone is regularly measured at ground stations and sampled infrequently through balloon, lidar, and crewed aircraft platforms, which have demonstrated characteristic patterns with altitude. Here, to better resolve vertical profiles of ozone within the atmospheric boundary layer, we developed and evaluated an uncrewed aircraft system (UAS) platform for measuring ozone and meteorological parameters of temperature, pressure, and humidity. To evaluate this approach, a UAS was flown with a portable ozone monitor and a meteorological temperature and humidity sensor to compare to tall tower measurements in northern Wisconsin. In June 2020, as a part of the WiscoDISCO20 campaign, a DJI M600 hexacopter UAS was flown with the same sensors to measure Lake Michigan shoreline ozone concentrations. This latter UAS experiment revealed a low-altitude structure in ozone concentrations in a shoreline environment showing the highest ozone at altitudes from 20–100 m a.g.l. These first such measurements of low-altitude ozone via a UAS in the Great Lakes region revealed a very shallow layer of ozone-rich air lying above the surface.
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Using an Unmanned Aerial System to Characterize Low Altitude Ozone Gradient Measurements in a Northern Wisconsin Forest
Ozone deposition measurements in forested environments are of interest to constrain background processes in models as well as better identify ozone exposure to the ecosystem. Ozone deposition in forested environments can arise through stomatal conductance in plants and dry deposition to soils. As a part of the CHEESEHEAD 19 field campaign, ozone measurements were obtained at two different heights (120 m and 30 m) on a tall tower. In comparison to those measurements, a hexacopter UAS was flown with a small, lightweight ozone monitor and meteorological sensor measuring temperature and humidity. The hexacopter was hovered at certain altitudes to determine ozone concentration gradients. The vertical gradients observed will be discussed in context of tower ozone concentration measurements and other meteorological parameters
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- Award ID(s):
- 1918850
- PAR ID:
- 10458426
- Date Published:
- Journal Name:
- Transactions American Geophysical Union
- ISSN:
- 2379-6723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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