Original_Source_URL: ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/wais2015ch4.txt Description: Ultra-high temporal resolution methane concentration data from West Antarctic Ice Sheet (WAIS) Divide (WD) ice core obtained by online, continuous technique (see Stowasser et al., 2012). 1714 m of ice core were analyzed using 3 different laser spectrometers during two laboratory campaigns of 2-3 months duration in early 2012 (1804-2621 m) and 2013 (2709-3404 m). Please refer to Table S1 in Rhodes et al. (2015) for precision, accuracy, and time/depth resolution information. Data provided here are cubic smoothing spline fit at 2 year spacing to the raw time-integrated data. Please refer to Supplementary Information in Rhodes et al. (2015, doi:10.1126/science.1262005) for more details.