Role of minerogenic particles in light scattering in lakes and a river in central New York

Abstract

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Optical characterizations and pursuit of optical closure for the western basin of Lake Erie through in situ measurements

“…The positive dependence ofb bp on metrics of inorganic particle contributions to particle populations has been reported Peng et al, 2009), and is expanded upon for this study subsequently. Wide deviations from the Petzold value have also recently been reported for other lacustrine systems, including eastern Lake Superior and Keweenaw Bay (Peng et al, 2009), and several lakes in central New York (Peng et al, 2007).…”

“…An analysis of theb bp − ISPM:SPM relationship is presented for λ = 650 nm (Fig. 4), a wavelength adopted in several earlier studies Peng et al, 2007Peng et al, , 2009Peng and Effler, in press). According to linear least-squares regression [b bp = 0.039 · (ISPM:SPM) − 2.83 × 10 − 3 ], the spatial differences in ISPM:SPM explained 92% of the differences observed forb bp (650).…”

Optical closure in lakes with contrasting extremes of reflectance

“…The difference, though not large, is consistent with the fact that the lakes are not pure suspensions of glacial flour. The bulk particulate backscatter fraction is necessarily smaller than that of the component having the highest value in isolation (Peng et al 2007). Similarly, particulate backscattering fractions for the humic lakes (ca.…”

Optical variability of seawater in relation to particle concentration, composition, and size distribution in the nearshore marine environment at Imperial Beach, California

“…In principle, the in‐depth mechanistic understanding of such complex optical variability could be addressed through a reductionist approach [ Stramski et al , 2001, 2004a], in which the knowledge about optically significant water constituents is available at a significant level of detail for a number of particle functional types that have distinctly different properties and play distinctly different optical and biogeochemical roles in the aquatic environment. Example research efforts in this direction include recent work in which a number of plankton species [ Stramski et al , 2001] or several different groups of minerogenic particles [ Peng and Effler , 2007; Peng et al , 2007] are treated as separate components affecting the bulk IOPs of water. However, a common approach in hydrologic optics over the past decades has been to address the optical variability at a much more general level of water composition parameterization in terms of bulk or aggregate characteristics of suspended particulate matter.…”

“…We recognize that measurements of the size distribution truncated within the 2–60 μ m range represent some limitation as particles outside this range also provide a contribution to the optical properties and particle mass concentration [e.g., Stramski and Kiefer , 1991; Carder and Costello , 1994; Jackson et al , 1997; Peng et al , 2007]. Practical considerations associated with a broad suite of measurements that required simultaneous execution were the main reason for this limitation in our experiments, but we note that it is desirable and generally possible to extend the size range by using multiple aperture tubes with a Coulter technique and/or multiple techniques for particle sizing.…”