Vertical profiling of air pollutants in unmanned aerial vehicle (UAV)

Atmospheric sampling onboard a multicopter unmanned aerial vehicle (UAV) is an economical and flexible air pollutant measurement technique for intermediate spatial scales of hundreds of meters. We conducted vertical profiling PM2.5 (particulate matter with diameter less than 2.5 micron), black carbon (BC) and ozone (O3) in highly urbanized areas of Macao and Shenzhen in subtropical South China using a multicopter unmanned aerial vehicle (UAV) platform. Seasonality of BC vertical profiles was observed in morning, afternoon and midnight flights, but not for evening flights. The analysis showed the shape of vertical profiles of BC and O3 can be affected by planetary boundary layer height (PBLH) and air mass origin.

We also deployed a UAV-based VOC sampler and conducted VOC samplings at two locations in South China over the canopy of subtropical forests. The collected VOC samples were analyzed offline by gas chromatography-mass spectrometry. The analysis by a gradient transport model suggests a large isoprene emission heterogeneity along the mountain slope at the scale of hundreds of meters for subtropical forests, which has not yet been well represented in most biosphere emission models. Strong eddy diffusion caused by the valley breeze may also contribute to the observed concentration differences.

Li Y., Liu B., Ye J., Jia T., Khuzestani R.B., Sun J.Y., Cheng X., Zheng Y., Li X., Wu C., Xin J., Wu Z., Tomoto M.A., McKinney K.A., Martin S.T., Li Y.J.*, and Chen Q.*, Unmanned Aerial Vehicle Measurements of Volatile Organic Compounds over a Subtropical Forest in China and Implications for Emission Heterogeneity, ACS Earth Space Chem., 2021, 5: 247-256.

Liu B., He M., Wu C., Li J., Li Y., Lau N.T., Yu J.Z., Lau A.K.H., Fung J.C.H., Hoi K.I., Mok K.M., Chan C.K., Li Y.J.*, Potential exposure to ne particulate matter (PM2.5) and black carbon on jogging trails in Macau, Atmos. Environ., 2019, 198: 23-33.

C. Wu*, B. Liu, D. Wu, H. Yang, X. Mao, J. Tan, Y. Liang, J.Y. Sun, R. Xia, J. Sun, G. He, M. Li, T. Deng, Z. Zhou, Y.J. Li*, Vertical profiling of black carbon and ozone using a multicopter unmanned aerial vehicle (UAV) in urban Shenzhen of South China, Sci. Total Environ., 2021, in press.