Annual and inter-annual variability in the diffuse attenuation coefficient and turbidity in an urbanized Washington lake from 2013 to 2022 assessed using Landsat-8/9

Jennifer A. Schulien; Tessa Julianne Code; Curtis L. DeGasperi; David Beauchamp; Arielle Tonus Ellis; Arni H. Litt

doi:10.3390/rs15205055

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Annual and inter-annual variability in the diffuse attenuation coefficient and turbidity in an urbanized Washington lake from 2013 to 2022 assessed using Landsat-8/9

Jennifer A. Schulien·Tessa Julianne Code·Curtis L. DeGasperi·David Beauchamp·Arielle Tonus Ellis·Arni H. Litt

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Abstract

Water clarity, defined in this study using measurements of the downwelling diffuse light attenuation coefficient (K d ) and turbidity, is an important indicator of lake trophic status and ecosystem health. We used in-situ measurements to evaluate existing semi-analytical models for K d and turbidity, developed a regional turbidity model based on spectral shape, and evaluated the spatial and temporal trends in Lake Washington from 2013 to 2022 using Landsat-8/9 Operational Land Imager (OLI). We found no significant trends from 2013 to 2022 in K d or turbidity when both the annual and full datasets were considered. In addition to the spring peak lasting from April through June, autumn K d peaks were present at all sites, a pattern consistent with seasonal chlorophyll a and zooplankton concentrations. There existed no autumn peak in the monthly turbidity dataset, and the spring peak occurred two months before the K d peak, nearly mirroring seasonal variability in the Cedar River discharge rates over the same period. The K d and turbidity algorithms were thus each more sensitive to different sources of water clarity variability in Lake Washington.

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Remote Sensing Article

Source-reported bounding extent: 47.49342533323215° to 47.76219367672758° latitude; -122.29668187426911° to -122.1703784589545° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Jennifer A. Schulien, Tessa Julianne Code, Curtis L. DeGasperi, David Beauchamp, Arielle Tonus Ellis, Arni H. Litt. 2023-10-21. Annual and inter-annual variability in the diffuse attenuation coefficient and turbidity in an urbanized Washington lake from 2013 to 2022 assessed using Landsat-8/9. https://doi.org/10.3390/rs15205055

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