Annual Fossil-Fuel CO2 Emissions: Uncertainty of Emissions Gridded by One Degree Latitude by One Degree Longitude R.J. Andres, T.A. Boden Carbon Dioxide Information Analysis Center Environmental Sciences Division Oak Ridge National Laboratory Oak Ridge, Tennessee 37831-6290 U.S.A. DOI: 10.3334/CDIAC/ffe.AnnualUncertainty.2016 Period of Record ---------------- 1950-2013 Methods ------- Andres et al. (2016) describes the basic methodology in estimating the uncertainty in the gridded fossil fuel data product (http://cdiac.ess-dive.lbl.gov/epubs/ndp/ndp058/ndp058_v2016.html, DOI: 10.3334/CDIAC/ffe.ndp058.2016). This uncertainty is gridded at the same spatial and temporal scales as the mass magnitude maps. This gridded uncertainty includes uncertainty contributions from the spatial, temporal, proxy, and magnitude components used to create the magnitude map of FFCO2 emissions. Throughout this process, when assumptions had to be made or expert judgment employed, the general tendency in most cases was toward overestimating or increasing the magnitude of uncertainty. Data File Structure and Naming Convention ----------------------------------------- There is a separate data file for each year. The files have a basename of 3compunc and an extension of yyyy where yyyy is the year (e.g., 2000). Uncertainty is depicted as a fractional units (e.g., 0.75 is 75% uncertainty and 1.75 is 175% uncertainty). Two identical sets of data are available: 1. Compressed 3compunc.yyyy.Z files (one file for each year). These files were compressed using the standard unix compression utility to speed downloading. You will need to uncompress them using the unix "uncompress *" command), and 2. One tar file (3compunc.tar) file which contains all 64 files in a compressed state. Before using the files, users will need to extract the files from the tar file using the "tar xvf 3compunc.tar" command and then uncompress the resulting files using the unix "uncompress *" command. We suggest the data should be plotted before directly incorporating the data into a model or other use. If read in correctly, the data should plot a map of the world with North at the top and East to the right. On each line, the data go from the 180-179 degrees west cell to the 179-180 degrees east cell until reading in the next line of data. In FORTRAN, the data were written with: parameter (maxlat=180, maxlon=360) C DISTRIBUTE ISOMASS ON GRID do 1200, i=1, maxlat do 1200, j=1, maxlon write (14, 1310) 3compunc (i,j) 1200 continue 1310 format (F6.4) References ---------- Andres RJ, Boden TA, Higon DM (2016) Gridded uncertainty in fossil fuel carbon dioxide emission maps, a CDIAC example. Atmos. Chem. Phys. Discuss. doi:10.5194/acp-2016-258. CITE AS: Andres, R.J., and T.A. Boden. 2016. Annual Fossil-Fuel CO2 Emissions: Uncertainty of Emissions Gridded by One Degree Latitude by One Degree Longitude. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tenn., U.S.A. doi 10.3334/CDIAC/ffe.AnnualUncertainty.2016