| Correlation between [PM2.5] and low frequency variation | ||
PDO (#) | SOI (#) | NP (#) | |
2/18/1999-3/31/2018 | 0.078 (228) | −0.069 (228) | −0.249 (228) |
Warm season | 0.131 (76) | −0.229 (76) | −0.136 (76) |
Cold season | 0.175 (116) | 0.107 (116) | −0.439 (116) |