Yes, but only courtesy of atomic bomb testing. Above-ground nuclear bomb blasts from 1945 to 1963 boosted the amount of C-14 in the atmosphere. Since 1963, the year the tests halted, the ratio of carbon-14 to the more common carbon-12 isotope has been slowly declining, allowing researchers to determine the date of wines to within a year, according to a new study from the University of Adelaide in Australia. The telltale carbon atoms in the soil are incorporated into the grape plants and, eventually, into the wine. The technique is aimed at detecting wine sold under faked vintage years – a problem some experts estimate affects up to five per cent of fine wine sales.