Adaption and use of a quadcopter for targeted sampling of gaseous mercury in the atmosphere
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We modified a popular and inexpensive quadcopter to collect gaseous mercury (Hg) on gold-coated quartz cartridges, and analyzed the traps using cold vapor atomic fluorescence spectrometry. Flight times averaged 16 min, limited by battery life, and yielded > 5 pg of Hg, well above the limit of detection (< 0.2 pg). We measured progressively higher concentrations upon both vertical and lateral approaches to a dish containing elemental Hg, demonstrating that the method can detect Hg emissions from a point source. Using the quadcopter, we measured atmospheric Hg near anthropogenic emission sources in the mid-south USA, including a municipal landfill, coal-fired power plant (CFPP), and a petroleum refinery. Average concentrations (± standard deviation) immediately downwind of the landfill were higher at ground level and 30 m compared to 60 and 120 m (5.3 ± 0.5 ng m−3, 5.4 ± 0.7 ng m−3, 4.2 ± 0.7 ng m−3, and 2.5 ± 0.3 ng m−3, respectively). Concentrations were also higher at an urban/industrial area (Memphis) (3.3 ± 0.9 ng m−3) compared with a rural/background area (1.5 ± 0.2 ng m−3). Due to airspace flight restrictions near the CFPP and refinery, we were unable to access near-field (stack) plumes and did not observe differences between upwind and downwind locations. Overall, this study demonstrates that highly maneuverable multicopters can be used to probe Hg concentrations aloft, which may be particularly useful for evaluating Hg emissions from remote landscapes and transient sources that are inadequately characterized and leading to uncertainties in ecosystem budgets.
KeywordsAtmospheric mercury Landfill Unmanned aerial vehicle Multicopter Coal-fired power plant Petroleum refinery Cold vapor atomic fluorescence spectrometry
We are grateful to Tekran Inc. and Brooks Rand Instruments for helpful advice and technical support, and several anonymous landowners for allowing us to sample from their private property. We thank Ms. Hailey Stewart for helping in the field and SKC Inc. for providing us sampling pumps for preliminary work.
- Deeds DA, Banic CM, Lu J, Daggupaty SJ (2013) Mercury speciation in a coal-fired power plant plume: an aircraft-based study of emissions from the 3640 MW Nanticoke Generating Station, Ontario, Canada. Geophys Res Atmos 118:1–17Google Scholar
- Diaz PV, Yoon S (2018) High-fidelity computational aerodynamics of multi-rotor unmanned aerial vehicles. AIAA SciTech Forum, Areospace Sciences Meeting, KissimmeeGoogle Scholar
- Huber ML, Laesecke A, Friend DG (2006) The vapor pressure of mercury. National Institute of Science and Technology NISTIR 6643, Brahmapur, p 17Google Scholar
- McGonigle AJS, Aiuppa A, Giudice G, et al (2008) Unmanned aerial vehicle measurements of volcanic carbon dioxide fluxes. Geophys Res Lett 35(6)Google Scholar
- Rossi M, Brunelli, D, Adami A, Lorenzelli L, Menna F, Remondino F (2014) Gas-drone: portable gas sensing system on UAVs for gas leakage localization. Sensors 1431–1434Google Scholar
- Slemr F, Ebinghaus R, Brenninkmeijer CAM, Hermann M, Kock HH, Martinsson BG, Schuck T, Sprung D, van Velthoven P, Zahn A, Ziereis H (2009) Gaseous mercury distribution in the upper troposphere and lower stratosphere observed onboard the CARIBIC passenger aircraft. Atmos Chem Phys 9(6):1957–1969CrossRefGoogle Scholar
- United Nations Environment Programme (2013) Technical background report for the global mercury assessment 2013. AMAP, OsloGoogle Scholar
- USEPA United States Environmental Protection Agency (1999) Compendium method IO-5, sampling and analysis for vapor and particle phase in ambient air utilizing cold vapor atomic fluorescence spectrometry (CVAFS). EPA/625/R-96/010aGoogle Scholar
- USEPA United States Environmental Protection Agency (2010) Toxic release inventory. <http://www.epa.gov/tri/>
- Yoon S, Diaz PV, Boyd Jr DD, Chan WM, Theodore CR (2017) Computational aerodynamic modeling of small quadcopter vehicles. American Helicopter Society (AHS) 73rd Annual Forum, Fort Worth, TexasGoogle Scholar