Characteristics of Atmospheric Compositions in the Background Area of Yangtze River Delta during Heavy Air Pollution Episode

Figure 2

Daily numbers of fire spots in different sectors: northwest sector: 100°E–119.733°E, 30.3°N–48°N; southwest sector: 100°E–119.733°E, 22°N–30.3°N; northeast sector: 119.733°E–130°E, 30.3°N–48°N; and southeast sector: 119.733°E–130°E, 22°N–30.3°N.