Preliminary analysis of the spatial and temporal patterns of aerosols and their impact on climate in Malaysia using MODIS satellite data

摘要

Research on atmospheric aerosols has become an important component in atmospheric studies due to its tremendous implications to radiation budget, climate change, hydrological and carbon cycles. Several recent studies have analysed the spatio-temporal patterns of aerosols and their relationship with meteorological conditions which is essential to quantify regional and global climate changes. However, such analysis have been lacking in Malaysia although this region receives considerable amount of air pollutants from local sources and neighbouring countries. Therefore, an attempt has been undertaken in this study to analyse the spatial and temporal patterns of aerosols in Peninsular Malaysia and explore the link between aerosols and meteorological variables. More specifically the monthly periodicities in atmospheric aerosols have been analysed using aerosol optical depth (AOD) product (level 2 data) from Moderate Resolution Imaging Spectro-radiometer (MODIS) satellite data covering years 2000-2009. Subsequently the AOD has been associated with meteorological variables (surface measurements) of daily minimum and maximum temperature, solar radiation, and relative humidity. Preliminary results of this study show that AOD is relatively higher in the dry season months (September and October). Spreading and intensifying fire locations in Indonesia contributed to a further increase in the AOD. Predominating southwest wind directions transported the aerosols to the north-east (Peninsular Malaysia) and caused subsequently high pollution levels. Association between AOD and climate show no significant correlation. This could be due to the monthly resolution of climate data used. Results presented in this study will be useful to understand how and to what extent human perturbations such as anthropogenic aerosol emissions serve as an agent of climate change.