Carl J. Legleiter Lee R. Harrison 2019 The data are contained with a comma-separated values (*.csv) text file. Reston, VA U.S. Geological Survey https://doi.org/10.5066/F7Q52NZ1 Field spectra were collected from a reach of the upper Sacramento River in northern California, September 11-14, 2017, to support research on remote sensing of rivers. Reflectance measurements were made from a boat near the confluence of Cottonwood Creek with the Sacramento River using an Analytical Spectral Devices FieldSpec3 spectroradiometer operated in reflectance mode. The depth at each spectral measurement location was interpolated from field measurements of depth obtained with an acoustic Doppler current profiler and an echo sounder. This data release provides both the reflectance spectra and the interpolated depths and can be used to develop relationships between depth and reflectance for mapping river bathymetry from field spectra or passive optical remotely sensed data. These field spectra were used to establish relationships between depth and reflectance that could be used to infer water depth from passive optical image data or field spectra. This kind of depth information could be incorporated into techniques for measuring river discharge from remotely sensed data. 20170911 20170914 ground condition Complete None planned -122.22564697143 -122.13226318237 40.415254104808 40.344117328972 USGS Thesaurus field spectra reflectance depth USGS Metadata Identifier USGS:5ababe74e4b081f61abb4e2b Geographic Names Information System (GNIS) Sacramento River California none none Carl J. Legleiter U.S. Geological Survey Geomorphology and Sediment Transport Laboratory Research Hydrologist mailing and physical

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Golden CO 80403 US 303-271-3651 cjl@usgs.gov National Oceanographic and Atmospheric Administration (NOAA) Southwest Fisheries Science Center No formal attribute accuracy tests were conducted No formal logical accuracy tests were conducted Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. No formal positional accuracy tests were conducted No formal positional accuracy tests were conducted Water depths at each spectral measurement location were interpolated from depth measurements made by a SonTek RiverSurveyor S5 acoustic Doppler current profiler (ADCP) that also provided a GPS position for each depth measurement location. The field spectra were measured from a spar extending out away from a boat. A Trimble Geo7X GPS receiver was mounted on the spare near the spectroradiometer and used to record GPS positions for the spectral measurements, as well as GPS time stamps. The time stamps from the GPS and the file save times from the spectroradiometer then were used to link each field spectrum to a spatial location. The locations of the depth (from the ADCP) and reflectance (from the spectroradiometer) measurements then were transformed to a channel-centered coordinate system as described by (Legleiter, C.J. and Kyriakidis, P.C., 2008. Spatial prediction of river channel topography by kriging. Earth Surface Processes and Landforms, 33(6): 841-867) and then linear interpolation was used to estimate the depth at each spectral measurement location. 20180209 Carl J Legleiter USGS Geomorphology and Sediment Transport Laboratory mailing and physical

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Golden CO 80403 US 303-271-3651 cjl@usgs.gov The field spectra were obtained with an Analytical Spectral Devices (ASD) FieldSpec3 spectroradiometer operated in reflectance mode, which involved periodically (approximately every 10 minutes) pointing the sensor at a white reference panel that served as a 100% reflectance standard. Subsequent measurements of the upwelling spectral radiance from the river channel were then normalized by the radiance from the white reference panel to obtain reflectance values. The data initially were saved in the native .asd file format and then imported to MATLAB via a custom function developed to read .asd data files. All of the spectra were plotted and obvious outliers (for example, when the white reference panel was still in the field of view) were removed. The spectra were subset from the original wavelength range from 375 to 1050 nm to 400 to 900 nm due to excessive noise at shorter and longer wavelengths. The spectra then were smoothed by twice applying a third-order Savitzky-Golay filter with a frame width of 15 nm. 20180209 Carl J Legleiter USGS Geomorphology and Sediment Transport Laboratory mailing and physical

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Golden CO 80403 US 303-271-3651 cjl@usgs.gov Sacramento River, California Point Transverse Mercator 0.9996 -123.0 0.0 500000.0 0.0 coordinate pair 0.01 0.01 METERS NAD83 NAD83 6378137.0 298.257222101 SacFieldSpectra Field measurements of water depth (m) and spectral reflectance at wavelengths from 400-900 nm Producer defined Easting Easting (X) coordinate of the spectral measurement location in meters based on differentially corrected GPS positions from the Trimble Geo7X receiver mounted on the spar extending out from the boat from which the spectra were measured. Easting coordinates are listed in the first column of the SacFieldSpectra.csv file. Beginning with the third line (row) of this file, each line (row) represents a different spectral measurement location. Producer defined 568150 568250 meters Northing Northing (Y) coordinate of the spectral measurement location in meters based on differentially corrected GPS positions from the Trimble Geo7X receiver mounted on the spar extending out from the boat from which the spectra were measured. Northing coordinates are listed in the second column of the SacFieldSpectra.csv file. Beginning with the third line (row) of this file, each line (row) represents a different spectral measurement location. Producer defined 4469550 4469700 meters Depth Water depth in meters, interpolated at the spectral measurement location based on water depth measurements obtained with an acoustic Doppler current profiler (ADCP) and echo sounder. Depths are listed in the third column of the SacFieldSpectra.csv file. Beginning with the third line (row) of this file, each line (row) represents a different spectral measurement location. Producer defined 0 3.1 meters Reflectance (%) at wavelength (nm) Spectral reflectance measured with an Analytical Spectral Devices (ASD) spectroradiometer at wavelengths from 400-900 nm with a 1 nm spectral sampling interval. The wavelengths are listed in the second line (row) of the SacFieldSpectra.csv file and each column contains the reflectance values for that wavelength at each spectral measurement location. Beginning with the third line (row) of this file, each line (row) represents a different spectral measurement location. Producer defined 0 100 percent U.S. Geological Survey - ScienceBase mailing and physical

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Denver CO 80225 USA 1-888-275-8747 sciencebase@usgs.gov Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. The data you have secured from the U.S. Geological Survey (USGS) database identified as "Field spectra from the upper Sacramento River in northern California, September 11-14, 2017" have not received USGS approval and as such are provisional and subject to revision. The data are released on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from its authorized or unauthorized use. Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein. The data are provided in a .csv file that can be read in a text editor (e.g., Notepad), spreadsheet (e.g., Excel), or numerical computing (e.g., MATLAB) software package. 20200831 Carl J Legleiter U.S. Geological Survey Geomorphology and Sediment Transport Laboratory Research Hydrologist mailing and physical

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Golden CO 80403 US 303-271-3651 cjl@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998