tailieunhanh - Optical closure in a complex coastal environment: particle effects

The purpose of this study is to review the literature on population and environment to identify the main strands of thought and the salient features and assumptions that lie behind them, and to guide the reader through what is a very diverse and confusing, yet rapidly expanding, field of study. We begin with a review of the historical perspective from Malthus and his capitalist and socialist critics, through Boserup’s thesis and other neoclassical economists, to the recent ideological war between the “neo-Malthusians” and the “cornucopians.” . | Optical closure in a complex coastal environment particle effects Grace Chang 1 Andrew Barnard 2 and J. Ronald V. Zaneveld2 1Ocean Physics Laboratory University of California Santa Barbara 6487 Calle Real Suite A Goleta California 93117 USA 2WET Labs Inc. 620 Applegate Street Philomath Oregon 97370 USA Corresponding author Received 23 April 2007 revised 5 September 2007 accepted 6 September 2007 posted 7 September 2007 Doc. ID 82300 published 25 October 2007 An optical dataset was collected on a mooring in the Santa Barbara Channel. Radiative transfer modeling and statistical analyses were employed to investigate sources of variability of in situ remote sensing reflectance rrs x 4 m and the f Q ratio. It was found that the variability of inherent optical properties and the slope of the particle size distribution Ệ were strongly related to the variability of rrs x 4 m . The variability of f Q was strongly affected by particle type characteristics. A semianalytical radiative transfer model was applied and effects of variable particle characteristics on optical closure were evaluated. Closure was best achieved in waters composed of a mixture of biogenic and minerogenic particles. 2007 Optical Society of America OCIS codes . 1. Introduction Significant advances in measurement techniques for the inherent optical properties IOPs properties that do not depend on the radiance distribution and apparent optical properties AOPs properties that depend on the IOPs and the radiance distribution of seawater 1 have been made recently. Specifically the spectral backscattering coefficient can now be measured in situ at a wide range of temporal and spatial scales and radiometric quantities and measurements of absorption scattering and attenuation coefficients can now be made at hyperspectral resolution 100 wavelengths in the visible . Despite these technological developments the forward and inverse problems in ocean optics . optical .