Real-time Forecasting Method of Urban Air Quality Based on Observation Sites and Thiessen Polygons

This paper proposes a real-time urban air quality forecasting method based on monitoring sites and Thiessen polygon. Firstly, the concentration of pollutants affecting air quality is obtained through the real-time observations of the monitoring sites deployed in wireless sensor network, according to which the air quality index (AQI) can be calculated and air quality levels and categories can be graded. Then, Thiessen polygons are constructed based on the monitoring sites and the air quality conditions from the only site within any polygon will be the representative to that of any other points within this polygon. Finally, the monitoring sites and Thiessen polygons rendered with standard air quality colors will be visualized on a geographical map for the realization of real-time forecasting method taking Thiessen polygons as forecasting units. Taking Shanghai city as an example, a real-time and visualized air quality prediction platform has been constructed in downtown Shanghai city, the real-time visualization of urban air quality forecasting and early warnings under the constraints of Thiessen polygon have been realized.