| Summary: | The goal of this project was to test the application of spectral depth models to quantify lake water volumes on the Inner Arctic Coastal Plain of Alaska. Lakes in this area tend to be deeper than those nearby and store a significant amount of the region’s water, making them important in terms of energy balance, as ecological habitat, and as water sources for infrastructure (e.g. ice roads). Due in part to their depth, these lakes have often been neglected by the limited number of prior studies that also focus on lakes in northern Alaska. Techniques employed by these studies limit the magnitude, precision, and/or scale at which depths can be assessed. By analyzing remotely sensed lake color using a method typically reserved for coastal bathymetry mapping, we are able to predict deeper depths and thus more accurately evaluate deep Arctic lake water volumes. This dataset includes 30 meter resolution bathymetry rasters for 17 lakes on the Alaskan Arctic Coastal Plain. These depth maps were created using linear and exponential models tuned with sonar depth measurements (depth dataset: doi:10.18739/A2SN01440) and applied to a Landsat-8 image (image ID: LC08_L1TP_077011_20160805_20170222_01_TI). The 12 model variants we tested were each distinguished by the two Red-Green-Blue (RGB) bands used, linear or exponential growth pattern, and simple or transform ratio. We were able to successfully tune models at the scale of an individual lake, predicting depth with an average model uncertainty (based on root mean squared error) of 1.44 meters. Volumes derived from the provided bathymetry rasters may be useful for understanding the distribution of water across northern Alaska and providing context for future changes in the landscape. Models were derived in part from: Stumpf, R. P., Holderied, K., and Sinclair, M. (2003). Determination of water depth with high-resolution satellite imagery over variable bottom types. Limnology and Oceanography, 48(1), 547-606. Sonar depth points provided by: Simpson, C. and Arp, C. (2018). Sonar Depth Measurements at Lakes on the Inner Arctic Coastal Plain of Alaska, July 2017. Arctic Data Center. doi:10.18739/A2SN01440 [https://doi.org/10.18739/A2SN01440]
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