| Summary: | Barrow, Alaska is in a region dominated by Arctic tundra of which a substantial part is covered by lakes and ponds. Despite their dominance in the landscape, freshwater ecosystems in the Arctic have been insufficiently studied. It is clear that furthering understanding of how Arctic water bodies are responding to warming will depend on the analysis of changes in the concentration of organic and inorganic constituents in the water; however, scientists are faced with the task of sampling many remote sites in a relatively hostile environment. Thus, the exploration and incorporation of remote methods for monitoring changes in water quality. However, ponds are often excluded from remote sensing studies due their shallow depth and their small size, leading to difficulty in selecting a platform suitable for their small spatial area, and generally shallow depth. The objective of this study was to examine the utility of established optical remote sensing indices collected from both ground-based (JAZ spectrometer) and satellite-based (WorldView-2) measurements of open water reflectance for predicting water quality of arctic tundra ponds. Multiple strong relationships were found between environmental parameters and ground-based reflectance from the JAZ spectrometer. Ground based reflectance appeared to be a strong predictor for measurements of chlorophyll, total suspended solids (TSS) and dissolved carbon compounds. Some of the most useful indices appeared to be the single wavelengths at 682 nm (Index 18) and 806 nm (Index 16), as well as the multiple wavelength ratios 710+820/740 (Index 6), 710+820/675+740 (Index 8) and 700/400 (Index 5). We found that ponds with different characteristics had unique reflectance signatures that could, at least in part, be associated with the differing water chemistries of these different pond types. High concentration of dissolved carbon compounds, especially dissolved organic carbon (DOC) and C440 , in thermokarst ponds in particular, led to very unique signatures and should be examined ...
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