LCC Network Data Steward(Point of Contact), Arctic Landscape Conservation Cooperative(administrator), 2013-08-15(lastUpdate), 2012-08-16(Publication), Fish Creek Watershed Data, https://www.fws.gov/science/catalog, https://www.sciencebase.gov/catalog/item/5a39474ce4b0d05ee8b40906
Summary
Stream physical parameter time series files for six or more beaded streams on the North Slope of Alaska in the Fish Creek Watershed near Nuiqsut. These include time series of water temperature (pool bed and surface and channel runs) and pool stage and correspond stream discharge developed from a rating curve.
Summary
Stream physical parameter time series files for six or more beaded streams on the North Slope of Alaska in the Fish Creek Watershed near Nuiqsut. These include time series of water temperature (pool bed and surface and channel runs) and pool stage and correspond stream discharge developed from a rating curve.
These folders contain .csv files of parameter time series collected year round (temperature) and during periods of channel flow without ice-affected conditions. Generally, bed pressure transduces (U20) are anchored to the bed of deep pool that serve as stable control points. These sensors read hourly pressure and temperature, which using local barometric pressure is converted to depth using the most current version of Onset Software. Similar pressure transducers are also placed in channel runs primarily to measure temperature, but also as a backup to control point pool measurements and to indicate the end of early fall flow. Surface pool temperature are measured hourly using an Onset computer U12-015 water temperature data logger is affixed to the rope 30 cm below the float. All sensor specifications are shown below. All instruments are retrieved and downloaded in mid-June after snowmelt peak flow and again in late August or early September. Stream discharge records are developed following standard methods used by the U.S. Geological Survey’s stream gaging program. These ideally include making at least eight measurements of discharge near the gaging site to capture the full range of stream flow in a typical year with 3-4 measurement from snowmelt peak discharge and early peakflow recession (mid-June), 2-3 measurements during late peakflow recession (late June to early July), 2-3 measurements during mid-summer baseflow, and 2-3 measurements during late baseflow (late August). Rise-to-peak flows are always ice-affected and are typically not included in rating curves and early winter baseflow to flow cessation are evaluated based on stream temperature measured in channel runs. Water level measurements at staff gages are made during each flow measurements and compared to sensor measurements during data processing. Discharge measurements are made using the Velocity-Area Method either with a SonTek ADCP or Hach 950 Electromagetic velocity meter mounted to a top-setting wading rod (0.6 or 0.2/0.8 method depending on depth) at 20 increments across the channel cross-section not capturing more than 10% of flow per increment. Measurements are periodically repeated to ensure less than 5% variability among individual points. Discharge values are automatically calculated using instrument software and periodically downloaded and manually checked for accuracy in a spreadsheet. Staff gages are periodically resurveyed and compared to a secondary datum to ensure stability. Rating curves are developed during the next year, once data is downloaded for the previous end-of winter flows. At this time, stage records are corrected to staff gauge measurements with sensor movement during download and servicing joined to a continuous datum. Curves are fit to stage-discharge data based on a best fit of either power, exponential, or a polynomial model based on comparison of residuals and overall coefficient of determination (r2) value. Separate high and low flow equations are often employed based on model fit. Currently we develop separate rating curves per year and are working to develop long-term rating curves for each station. All loggers record hourly measurements on the hour using Alaska Standard Time (AKST). Specific column heading a provided for each file along with units. Once downloaded, data is quality controlled first using Onset Software to correct measurements for barometric pressure and temperature and according to field measurements typically recorded in April and August. Temperature data is corrected to lab measured calibration equations (linear corrections based on temperature and water level variations) and data is plotted versus time and other parameters to identify outliers, which are flagged as NaN. Other discrepancies that cannot be corrected based on field observations are also flagged as NaN. Hourly datasets are summarized as daily mean values for full 24-hr monitoring periods.
