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Knowledge of the parameters that are related to the optical properties of atmospheric aerosols is essential for the determination of their climatic effects, development of techniques for remote sensing of aerosol from space or the necessary correction of atmospheric effects in satellite imagery (Sanchez, et al., 1998). The AOT values were derived from the measured transmittance. AOT, τ, is a measure of aerosol loading in the atmosphere (Christopher, et al., 2002). Generally, a higher AOT value indicates higher column of aerosol loading and therefore low visibility (Wang and Christopher, 2003). Atmospheric components (aerosol and molecules) scatter and absorb solar radiation. This study investigated the use of a handheld spectroradiometer for the retrieval of atmospheric optical thickness (AOT) values over Penang Island. A set of spectroradiometer measured transmittance data was used to derive the aerosol optical thickness (AOT) in the atmosphere. The transmittance values were measured in spectral region from 350nm to 1050nm at the earth surface. The locations were determined with a Global Positioning System (GPS) receiver. We selected the values at 550nm for the present analysis. This study introduces an economical and a simple technique for retrieval of AOT for remote sensing application. The transmittance values were measured around the PenangIsland. Particulate matters of size less than 10 micron (PM10) were collected simultaneously with the acquisition of the transmittance measurements. The results of the analysis indicated that the AOT values were linearly correlated with the PM10 readings. The objective of this study was to explore the relationship between aerosol optical thickness (AOT) derived from the spectroradiometer transmittance measurements and the correlation of particulate matter less than 10 micron (PM10). PM10 values were colleted simultaneously with the transmittance measurements. This study showed that there was a good correlation between the derived AOT and the measured PM10. In this study, we present results from ground-based measurements for PM10 mapping. Many researchers have conducted satellite monitoring of the AOT [Husar, et al., (1997) and Liu, et al., (2002), Jiang, et al., (2007) and Guo, et al., (2009)]. In this study, we present a method for air quality mapping from ground-based measurements. Typically, ground based measurements were made with a device of sun photometer. In this study, our purpose is to generate AOT and PM10 maps over Penang Island, Malaysia by using a handheld spectroradiometer. The transmittance values were measured using a handheld |
