Characterisation of particle mass and number concentration on the east coast of the Malaysian Peninsula during the northeast monsoon

Doreena Dominick, Mohd Talib Latif, Liew Juneng, Md Firoz Khan, Norhaniza Amil, Mohammed Iqbal Mead, Mohd Shahrul Mohd Nadzir, Phang Siew Moi, Azizan Abu Samah, Matthew J. Ashfold, William T. Sturges, Neil R P Harris, Andrew D. Robinson, John A. Pyle

Research output: Contribution to journalArticlepeer-review

22 Citations (Scopus)
5 Downloads (Pure)


Particle mass concentrations (PM10, PM2.5 and PM1) and particle number concentration ((PNC); 0.27 μm ≤ Dp ≤ 34.00 μm) were measured in the tropical coastal environment of Bachok, Kelantan on the Malaysian Peninsula bordering the southern edge of the South China Sea. Statistical methods were applied on a three-month hourly data set (9th January to 24th March 2014) to study the influence of north-easterly winds on the patterns of particle mass and PNC size distributions. The 24-h concentrations of particle mass obtained in this study were below the standard values detailed by the Recommended Malaysian Air Quality Guideline (RMAQG), United States Environmental Protection Agency (US EPA) and European Union (EU) except for PM2.5, which recorded a 24-h average of 30 ± 18 μg m-3 and exceeded the World Health Organisation (WHO) threshold value (25 μg m-3). Principal component analysis (PCA) revealed that PNC with smaller diameter sizes (0.27-4.50 μm) showed a stronger influence, accounting for 57.6% of the variability in PNC data set. Concentrations of both particle mass and PNC increased steadily in the morning with a distinct peak observed at around 8.00 h, related to a combination of dispersion of accumulated particles overnight and local traffic. In addition to local anthropogenic, agricultural burning and forest fire activities, long-range transport also affects the study area. Hotspot and backward wind trajectory observations illustrated that the biomass burning episode (around February-March) significantly influenced PNC. Meteorological parameters influenced smaller size particles (i.e. PM1 and Dp (0.27-0.43 μm)) the most.

Original languageEnglish
Pages (from-to)187-199
Number of pages13
JournalAtmospheric Environment
Early online date16 Jul 2015
Publication statusPublished - Sep 2015


  • Aerosols
  • Biomass episodes
  • Long-range transport
  • Meteorology
  • Multivariate analysis

Cite this