DOI: 10.6084/m9.figshare.1615873.v1
title: Sepulveda et al. The shifting climate portfolio of the Greater Yellowstone Area

description: http://dx.doi.org/10.6084/m9.figshare.1615873 Data sets and supplementary information for Sepulveda et al. The shifting climate portfolio of the Greater Yellowstone Area. All units are metric (mm, degrees C, cubic meters). Missing values are marked with "nan," which stands for "not a number." Missing entries are due either to completely missing data or because time periods had insufficent data for an accurate calculation. See Sepulveda et al. for details. SNOTEL temperature data were identical to NRCS sources at the time of writing, but NRCS plans recalculate their historical datasets in the near future. This may result in some differences between the data provided here and the data that is in future available from the NRCS web sites. Files with "normalized data" were normalized as follows: 1. For each stream gage or SNOTEL, separately calculate the mean and standard deviation for each parameter during the period spanning water years 1993 - 1994 through 2012-2013. These are defined as "mean" and "sd." 2. For each stream gage or SNOTEL, separately calculate the z value as z = (x-mean) / sd for each parameter for each water year, where x = the annual value for a parameter at a specific gage / SNOTEL. This results in normalized time series for each gage / SNOTEL that are all on a common scale of measure. 3. To find the zone or "overall" mean for a particular parameter for a particular water year, average all the z-scores available in that year for that parameter. The zonal z values appear in the columns labelled "overall_{parameter} in the normalized files below." 4. Stations or gages that do not have complete data during the reference period 1993 - 1994 through 2012 - 2013 (stations with short or poor quality records) have been excluded from normalization. You will notice that normalized values for these stations have been all replaced with "nan." This is to ensure that the same number of gages / stations were used to calculate the overall zone averages and sd (step 2) for each year. This restriction was relaxed for the SNOTEL monthly Tmax, Tmin, and Precip files presented below because too many SNOTEL stations were eliminated, and upon examination, it was found that each station only had a handful of missing months. We can relax this condition for all files, but exploratory graphs show that it produces jump or discontinuous time series that seem less likely to reveal true patterns. Notice that "peak date" and other non-numeric fields cannot be normalized because they are expressed as calendar references, e.g. 6/01/1958. These columns are all replaced with "nan" in the normalized files, but there are numeric equivalents that have been normalized. For example, stream peak dates are available numerically in the variable "peak_index," which is the numbered day of the water year at which peak occurred. Files: meta.csv - metadata describing the weather stations used.<br>---<br>tx_reduced_stn_set_snotel_monthly_tmin.csv - monthly averages of daily Tmaxfrom TopoWx (Oyler et al) infilled and corrected station data files<br>--- tx_reduced_stn_set_snotel_monthly_tmax.csv - monthly averages of daily Tmax from TopoWx (Oyler et al) infilled and corrected station data files<br>--- tx_reduced_stn_set_snotel_seasonal_tmax.csv - Seasonal averages of tmax for snotel stations from TopoWx infilled and corrected station files<br>---<br>tx_reduced_stn_set_snotel_seasonal_tmin.csv - Seasonal averages of tmin for snotel stations from TopoWx infilled and corrected station files<br>---<br>tx_all_monthly_tmin.csv - monthly averages of daily tmin for all station types in the yellowstone area calculated from TopoWx infilled and corrected data sets<br>---<br>tx_all_monthly_tmax.csv - monthly averages of daily tmax for all station types in the yellowstone area calculated from TopoWx infilled and corrected data sets<br>---<br>tx_all_seasonal_tmin.csv - seasonal averages of daily tmin for all station types in the yellowstone area calculated from TopoWx infilled and corrected data sets<br>---<br>tx_all_seasonal_tmax.csv - seasonal averages of daily tmax for all station types in the yellowstone area calculated from TopoWx infilled and corrected data sets<br>---<br>tx_all_daily_tmin.csv - daily tmin for all station types in the yellowstone area calculated from TopoWx infilled and corrected data sets<br>---<br>tx_all_daily_tmax.csv - daily tmax for all station types in the yellowstone area calculated from TopoWx infilled and corrected data sets --- Annual_SNOTEL_stats.csv - For each water year at each station in the GYA, the following variables are reported: Peak Snow Water Equivalent (PWE) - millimeters Peak snow day - day on which peak SWE occurred expressed as number of days since the start of the water year (October 1) Peak snow date - day on which peak swe occurred expressed as year / month Winter Length - Number of days with Snow Water Equivalent (SWE) greater than zero Melt - Number of days between peak SWE and complete melt --- april_1_swe.csv - Snow water equivalent (mm) on April 1 for each year at each station. ---<br>monthly_pwe.csv - For each month during each water year at each station, Peak Snow Water Equivalent (mm). Months are indicated in the header as numbers. For example, gunsight_pass_01 is the PWE for January at the Gunsight Pass SNOTEL station. --<br>Normalized_monthly_pwe_all_stations.csv - normalized monthly peak swe. See above for normalization procedure --<br>snotel_monthly_tmax.csv - monthly averages of daily tmax for snotel stations calculated from NRCS data. NOTE all SNOTEL temperature data are identical to NRCS sources at the time of writing but NRCS plans to recalculate their daily historical values in the near future. Future comparisons to NRCS web sites may reveal some differences. ---<br>snotel_monthly_tmin.csv - monthly averages of daily tmin for snotel stations calculated from NRCS data. --<br>melt_out_dates.csv - Day of complete melt out (zero swe) for each water year, expressed as number of days after October 1 ---<br>stream_summaries_05012014.csv -<br>For each water year at each station, the following variables are presented: - StationName_median_# (e.g. soda_boundary_01)= Median flow value (cubic meters per second) for the numbered month. Months are numbered 1 - 12 - StationName_min_# = Minimum daily flow (Cubic meters per second) for the numbered month. Months are numbered 1 - 12. - date_half_disch = Calendar date at which centroid of flow was reached - index_half_disch = Day of water year (number of days after October 1) on which centroid was reached - height_half_disch = flow rate (cubic meters per second) on the date that centroid of flow was reached -peak_date = Calendar date of peak flow - peak_index = Day of water year (number of days after October 1) on which peak flow occurred -peak_cms = Peak Flow (Cubic meters per second) - min_date, min_index, min_cms = Same as the last 3 above but for minimum flow during each water year - total_vol = total volume (cubic meters) of water for each water year -peak_minus_min = Peak flow rate - min flow rate -moving_25th_percentile_flow = 25th percentile flow (cubic meters per second) for the 10 year period including the water year listed and the previous 9 years. -days_below_moving_25th = # days in the listed water year that had flow below the moving 25th percentile -days_below_recent_25th = # days below the 25th percentile flow during the period 1981 - 2010. -gradient_index = A hydrograph "spikiness" index which is calculated as the sum of all the first derivative values in a water year -days_above_recent_winter_90th = The number of days during November - March in each water year that exceeds the November - March 90th percentile flow. 90th Percentile for Nov - Mar is calculated during the years 2001 - 2010 -days_below_recent_summer_10th = The numbers of days during July - September in each water year that are below the 10th percentile flow for July - September. 10th percentile calculated over 2001 - 2010. -days_below_recent_summer_25th = The number of days during July - September in each water year that are below the 25th percentile flow for July - September. 25th percentile is calculated over 2001 - 2010. -est_vals = The number of flow measurements in each water year that are estimated (have data flag e). Estimated values USUALLY occur when there is ice on the gage. ---<br>Normalized_stream_data_all_gages.csv - normalized stream statistics. See normalization procedure above.