Epoch

A

B

C

D

E

F

G

Length scale (km)

6.6

5.4

1.5

0.7

1.66

2.6

2.3

Time since rain (days)

16

1

2

<1

1+

1

2

Mean wind direction (˚)

168.9 ± 34.8

217.7 ± 34.6

176.9 ± 28.3

326.1 ± 44

148.4 ± 20.5

47.9 ± 30

34 ± 28

PM_2.5 (μg∙m⁻³)

20.5 ± 4.2

20.1 ± 4.2

6.1 ± 0.7

3.0 ± 0.5

13.7 ± 3.7

5.2 ± 0.8

7.6 ± 1.2

EPA class

Moderate

Moderate

Good

Good

Moderate

Good

Good

Mean temp (˚C)

25.6 ± 1

27.6 ± 1

26.3 ± 0.9

17.7 ± 0.8

24.3 ± 1.6

25.1 ± 0.6

27.6 ± 0.7

Mean pressure (mbar)

1009.3 ± 0.7

1011.6 ± 0.7

1010.6 ± 0.6

1023.3 ± 0.7

1016.7 ± 1.6

1012.9 ± 0.6

1011.8 ± 0.7

Mean humidity (%)

34 ± 2.5

47.5 ± 5

47 ± 2.5

10.9 ± 3.0

47.9 ± 7.4

52.6 ± 2.5

48.8 ± 2.3

Mean wind speed (m∙s⁻¹)

3.6 ± 1.6

3.8 ± 1.2

3.9 ± 1.3

3.8 ± 1.1

3.7 ± 0.5

3.2 ± 0.8

3.0 ± 0.8

Mean size (μm)

0.29

0.31

0.3

0.3

0.3

0.29

0.29