Stable hydrogen and oxygen isotopic compositions of precipitation samples from selected Delaware, Maryland, New Jersey, New York, and Pennsylvania National Atmospheric Deposition Program (NADP) sites

The stable hydrogen (delta 2H) and oxygen (delta 18O) isotopic compositions of more than 6,400 daily or weekly composite samples of precipitation from nine National Atmospheric Deposition Program (NADP) sites (DE02, MD07, NJ99, NY67, NY68, PA00, PA15, PA72, and PA98) in New York, New Jersey, Delaware, Maryland and Pennsylvania were analyzed on archived samples obtained from NADP over various time periods from as early as 1992. The samples are from the NADP National Trends Network (NTN) with weekly sample frequency, and the former NADP AIRMoN network, sampled daily within 24 hours of start of precipitation.  Data on site location, collection begin and end dates, sample volume and precipitation amounts were furnished from publicly-available NADP sources and were not evaluated for accuracy.  Measured values range between -255.6 and +25.5 per mil for delta 2H and between -33.66 and +5.39 per mil for delta 18O. This data set includes values from all the samples that were analyzed so that measurement uncertainty related to sample volume can be evaluated. Due to sample volume and storage times, some isotope-delta values have been flagged as being out of range for natural waters; however, the end user is responsible for evaluating all data for suitability to the intended purpose.
 
Data files provided here include the metadata as an .xml file, a Microsoft Office Excel .xlsx file with four spreadsheets containing the Introduction, Table 1, Table 2, and Table 3, and the individual data tables as comma-separated value .csv files. A plot of hydrogen versus oxygen isotopic compositions is also provided as a .jpg image. Data analysis was funded by the U.S Geological Survey (USGS) National Research Program, the USGS Water Availability and Use Science Program (WAUSP), and the USGS Next Generation Water Observing System (NGWOS) Program.