We report radiocarbon measurements of dissolved inorganic carbon (DIC) in surface water samples collected daily during 12 cruises to Station M in the northeast Pacific off central California. Individual surface Delta C-14 values ranged from 22 parts per thousand to 70 parts per thousand over 10 yr. Variability of average cruise values is highest during winter likely due to increased mixing. A general decrease of Delta C-14 values was observed at a rate of about 3 parts per thousand per year between 1994 and 2004, about half of that in atmospheric CO2 during this period (Levin and Kromer 2004). The Delta C-14 results ranged from 2-18 parts per thousand during individual cruises and were often significantly larger than the total uncertainty for individual measurements (+/- 3.9 parts per thousand). This indicates that a single Delta C-14 result from a surface site is not sufficient to capture the true variability of Delta C-14 in the surface ocean.