Himawari-8-derived diurnal variations in ground-level PM 2.5 pollution across China using the fast space-time Light Gradient Boosting Machine (LightGBM)

Wei, Jing; Li, Zhanqing; Pinker, Rachel T.; Wang, Jun; Sun, Lin; Xue, Wenhao; Li, Runze; Cribb, Maureen

Fine particulate matter with a diameter of less than 2.5 inline-formulaµm (inline-formulaPM2.5) has been used as an important atmospheric environmental parameter mainly because of its impact on human health. inline-formulaPM2.5 is affected by both natural and anthropogenic factors that usually have strong diurnal variations. Such information helps toward understanding the causes of air pollution, as well as our adaptation to it. Most existing inline-formulaPM2.5 products have been derived from polar-orbiting satellites. This study exploits the use of the next-generation geostationary meteorological satellite Himawari-8/AHI (Advanced Himawari Imager) to document the diurnal variation in inline-formulaPM2.5. Given the huge volume of satellite data, based on the idea of gradient boosting, a highly efficient tree-based Light Gradient Boosting Machine (LightGBM) method by involving the spatiotemporal characteristics of air pollution, namely the space-time LightGBM (STLG) model, is developed. An hourly inline-formulaPM2.5 dataset for China (i.e., ChinaHighinline-formulaPM2.5) at a 5 inline-formulakm spatial resolution is derived based on Himawari-8/AHI aerosol products with additional environmental variables. Hourly inline-formulaPM2.5 estimates (number of data samples inline-formula= 1 415 188) are well correlated with ground measurements in China (cross-validation coefficient of determination, CV-inline-formulaR2inline-formula= 0.85), with a root-mean-square error (RMSE) and mean absolute error (MAE) of 13.62 and 8.49 inline-formulaµg m−3, respectively. Our model captures well the inline-formulaPM2.5 diurnal variations showing that pollution increases gradually in the morning, reaching a peak at about 10:00 LT (GMTinline-formula+8), then decreases steadily until sunset. The proposed approach outperforms most traditional statistical regression and tree-based machine-learning models with a much lower computational burden in terms of speed and memory, making it most suitable for routine pollution monitoring.

Zitieren

Zitierform:

Wei, Jing / Li, Zhanqing / Pinker, Rachel T. / et al: Himawari-8-derived diurnal variations in ground-level PM2.5 pollution across China using the fast space-time Light Gradient Boosting Machine (LightGBM). 2021. Copernicus Publications.

Zugriffsstatistik

Gesamt:
Volltextzugriffe:
Metadatenansicht:
12 Monate:
Volltextzugriffe:
Metadatenansicht:

Grafik öffnen

Rechte

Rechteinhaber: Jing Wei et al.

Nutzung und Vervielfältigung:

Export