Dataset name: Atmospheric Carbon Dioxide Dry Air Mole Fractions from the NOAA ESRL Carbon Cycle Cooperative Global Air Sampling Network, 1968-2012 Varialbe name: co2 Reference of original data: Dlugokencky, E.J., P.M. Lang, K.A. Masarie, A.M. Crotwell, and M.J. Crotwell (2013), Atmospheric Carbon Dioxide Dry Air Mole Fractions from the NOAA ESRL Carbon Cycle Cooperative Global Air Sampling Network, 1968-2012, Version: 2013-08-28, Downloaded site: ftp://aftp.cmdl.noaa.gov/data/trace_gases/co2/flask/surface/. Downloaded Date: September 20, 2013 Downloaded by: Mingquan Mu Earth System Science, University of California, Irvine Name and Version of original source: N/A Start date: January 1968 End date: December 2012 Temporal resolution: monthly Spatial resolution: Site obervatons Unit: ppm Data format: ascii