Remote Sensing Letters Vol. 3, No. 4, July 2012, 335–342 Data-driven correction for light attenuation in shallow waters MARVIN WASHINGTON†, PHILEMON KIRUI‡, HYUN JUNG CHO*‡ and CELESTIN WAFO-SOH† †Department of Mathematics, Jackson State University, Jackson, MS 39217, USA ‡Department of Biology, Jackson State University, Jackson, MS 39217, USA (Received 18 February 2011; in final form 13 June 2011) Application of remote sensing to aquatic habitats is generally complex, due to the presence of optically active components that absorb or scatter light. According to the Beer–Lambert law, as electromagnetic energy travels through a medium, it is attenuated at an exponential rate determined by the physical and chemical properties of the medium. Determination of attenuation coefficients is complex for optically shallow inland and coastal waters due to bottom reflection and/or multi-path scattering. To better understand light attenuation in shallow waters, mathematical relationships between water depth and vertical attenuation coeffi- cient (K d ) were derived using experimental spectral data (400–900 nm). The model was used to estimate K d values at water depths that were beyond and in between the experimentally measured points (5–60 cm). The depth- and wavelength-dependent K d values were used to correct the measured spectral reflectance for the corre- sponding light attenuation to restore the bottom reflectance signals. After the correction, the spectral reflectance patterns measured above submerged aquatic plants appeared to include a restored signal from vegetation especially in the near-infrared (NIR) region. Comparison between the modelled spectra and the empirically measured spectra suggest that the proposed approach produced an effective model for light attenuation in optically shallow waters. 1. Introduction Application of remote sensing to aquatic habitats is generally complex due to the pres- ence of optically active components that absorb or scatter light. According to the Beer–Lambert law (Bhutiani et al. 2009), as incident electromagnetic energy travels through a medium (e.g. a water column), it is attenuated at an exponential rate deter- mined by the physical and chemical properties of molecules in the medium that scatter and absorb the energy. The attenuation coefficient (K d ) is the result of both absorption and scattering coefficients, where light is lost due to the combined effects of absorp- tion and scattering in an attenuating medium (Downing 2008). Both absorption and scattering are wavelength-dependent in pure water as short-wavelength energy is more prone to scattering and absorption increases with wavelength. In addition, the amount *Corresponding author. Email: hyun_jung.cho@jsums.edu Remote Sensing Letters ISSN 2150-704X print/ISSN 2150-7058 online © 2012 Taylor & Francis http://www.tandf.co.uk/journals DOI: 10.1080/01431161.2011.597791