| Month | “Soiling factor β” | “Dusty days/month” | Days with high AOD |
| Jan | 9.99 × 10−5 | 7 | 4 |
| Feb | 9.66 × 10−5 | 12 | 7 |
| Mar | 8.53 × 10−5 | 18 | 13 |
| Apr | 29.17 × 10−5 | 13 | 13 |
| May | 17.52 × 10−5 | 22 | 13 |
| Jun | 7.68 × 10−5 | 19 | 18 |
| Jul | 3.41 × 10−5 | 12 | 15 |
| Aug | 4.05 × 10−5 | 17 | 10 |
| Sep | 10.70 × 10−5 | 11 | 4 |
| Oct | 12.05 × 10−5 | 2 | 8 |
| Nov | 10.96 × 10−5 | 4 | 2 |
| Dec | 7.16 × 10−5 | 7 | 1 |
| Avg | 10.91 × 10−5 | 12.00 | 9.00 |