Publications

Wang, W; Mao, FY; Du, L; Pan, ZX; Gong, W; Fang, SH (2017). Deriving Hourly PM2.5 Concentrations from Himawari-8 AODs over Beijing-Tianjin-Hebei in China. REMOTE SENSING, 9(8), 858.

Abstract
Monitoring fine particulate matter with diameters of less than 2.5 mu m (PM2.5) is a critical endeavor in the Beijing-Tianjin-Hebei (BTH) region, which is one of the most polluted areas in China. Polar orbit satellites are limited by observation frequency, which is insufficient for understanding PM2.5 evolution. As a geostationary satellite, Himawari-8 can obtain hourly optical depths (AODs) and overcome the estimated PM2.5 concentrations with low time resolution. In this study, the evaluation of Himawari-8 AODs by comparing with Aerosol Robotic Network (AERONET) measurements showed Himawari-8 retrievals (Level 3) with a mild underestimate of about -0.06 and approximately 57% of AODs falling within the expected error established by the Moderate-resolution Imaging Spectroradiometer (MODIS) (+/-(0.05 + 0.15AOD)). Furthermore, the improved linear mixed-effect model was proposed to derive the surface hourly PM2.5 from Himawari-8 AODs from July 2015 to March 2017. The estimated hourly PM2.5 concentrations agreed well with the surface PM2.5 measurements with high R-2 (0.86) and low RMSE (24.5 mu g/m(3)). The average estimated PM2.5 in the BTH region during the study time range was about 55 mu g/m(3). The estimated hourly PM2.5 concentrations ranged extensively from 35.2 +/- 26.9 mu g/m(3) (1600 local time) to 65.5 +/- 54.6 mu g/m(3) (1100 local time) at different hours.

DOI:
10.3390/rs9080858

ISSN:
2072-4292