Table 1 Descriptive statistics of daily mortality, meteorological parameters and air pollutants of the urban areas in 4 cities of China during the warm period

All-cause mortality

83.7 ± 11.9

126

82.5

50

37.0 ± 7.1

71

37

18

14.4 ± 4.5

31

14

3

34.9 ± 7.8

56

35

16

Cardiovascular mortality (I00-I99)

37.9 ± 7.5

61

38

16

13.8 ± 4.1

31

14

2

3.4 ± 2.1

12

3

0

12.4 ± 4.0

26

12

4

Respiratory mortality (J00-J99)

9.1 ± 3.3

20

9

2

4.0 ± 1.9

12

4

1

0.8 ± 0.9

8

1

0

5.8 ± 2.6

14

5

1

Endocrine and metabolic mortality (E00-E90)

1.6 ± 1.1

6

2

1

1.7 ± 0.9

7

1

1

0.2 ± 0.5

4

0

0

1.7 ± 0.9

5

1

1

Diabetes mortality (E10-E14)

1.5 ± 1.1

6

1

0

1.6 ± 0.9

7

1

1

0.1 ± 0.2

2

0

0

1.6 ± 0.9

5

1

1

Digestive mortality (K00-K93)

2.7 ± 1.5

7

2

1

1.5 ± 0.8

6

1

1

0.4 ± 0.6

3

0

0

1.8 ± 1.0

6

1

1

Genitourinary mortality (N00-N99)

2.1 ± 1.1

6

2

1

1.3 ± 0.6

5

1

1

0.2 ± 0.4

3

0

0

1.2 ± 0.4

4

1

1

Male

50.1 ± 8.8

80

50

26

20.4 ± 5.0

38

20

5

9.3 ± 3.4

27

9

1

20.6 ± 5.4

36

21

6

Female

33.4 ± 6.5

54

33

18

16.6 ± 4.3

35

16

4

5.2 ± 2.4

14

5

1

14.2 ± 4.2

25

14

5

0-14 years

1.8 ± 1.0

7

2

1

1.3 ± 0.6

5

1

1

1.3 ± 0.6

5

1

1

1.4 ± 0.6

4

1

1

15-64 years

31.0 ± 6.3

54

31

14

8.7 ± 2.9

20

8

1

8.7 ± 3.5

22

8

1

10.5 ± 3.7

28

10

3

≥65 years

51.4 ± 8.6

82

51

31

27.9 ± 6.1

60

28

11

5.8 ± 2.4

15

5

2

24.1 ± 6.1

43

23

10

Maximum temp. (°C)

27.4 ± 3.5

37.1

27.6

13.2

30.0 ± 4.1

38.6

30.3

16.5

31.4 ± 2.4

37.9

31.8

21.8

29.9 ± 5.8

40.9

30.4

14.5

Mean temp. (°C)

22.5 ± 3.1

29.9

22.8

11.2

25.6 ± 3.7

34.5

25.8

14.3

28.1 ± 1.9

33

28.4

20.8

25.0 ± 4.6

34.9

24.9

13.3

Minimum temp. (°C)

17.8 ± 3.4

24.8

18

9

22.1 ± 3.9

30.8

22.6

9.4

25.7 ± 1.8

30.3

25.9

18.3

21.5 ± 3.8

30.6

21.4

12.3

Mean relative humidity (%)

72.1 ± 12.1

95

74

28

73.4 ± 11.6

98

74

37

76.1 ± 8.0

95

76

44

69.9 ± 16.4

94

71.8

26.1

Mean PM₁₀ (μg/m³)

63.3 ± 37.4

175

57

7.5

95.1 ± 48.6

485.3

87.7

14

49.7 ± 26.1

186.4

41.4

13.1

73.2 ± 31.6

188.3

68.8

13.2

Mean SO₂ (μg/m³)

22.5 ± 7.7

62

22.5

5

38.3 ± 17.8

114.7

35

5

19.7 ± 14.0

101.8

15.4

3.4

29.2 ± 11.6

70.5

28.6

8.7

Mean NO₂ (μg/m³)

39.8 ± 23.7

148.5

31

11

43.2 ± 14.8

118.3

41

13.3

43.8 ± 19.3

138.2

38.8

13.1

31.4 ± 10.8

63.2

30.0

9.0

Area

Urban area of whole city

Urban area of whole city

Urban area of whole city

3 of 19 districts in urban area