Article

Monsoonal differences and probability distribution of PM10 concentration

Environmental Monitoring and Assessment (Impact Factor: 1.59). 163(1):655-667. DOI: 10.1007/s10661-009-0866-0

ABSTRACT There are many factors that influence PM10 concentration in the atmosphere. This paper will look at the PM10 concentration in relation with the wet season (north east monsoon) and dry season (south west monsoon) in Seberang Perai,
Malaysia from the year 2000 to 2004. It is expected that PM10 will reach the peak during south west monsoon as the weather during this season becomes dry and this study has proved that
the highest PM10 concentrations in 2000 to 2004 were recorded in this monsoon. Two probability distributions using Weibull and lognormal were
used to model the PM10 concentration. The best model used for prediction was selected based on performance indicators. Lognormal distribution represents
the data better than Weibull distribution model for 2000, 2001, and 2002. However, for 2003 and 2004, Weibull distribution
represents better than the lognormal distribution. The proposed distributions were successfully used for estimation of exceedences
and predicting the return periods of the sequence year.

KeywordsExceedences-Lognormal distribution-Return period-Weibull distribution

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