Estimates of the anthropogenic global-integrated sea-air carbon dioxide (CO2) flux from 1990 to 2009, based on different models and measurements, range from –1.4 to –2.6 Pg C yr–1. The median values of anthropogenic CO2 for each method show better agreement and are: −1.9 for Pg C yr−1 for numerical ocean general circulation hind cast models (OGCMs) with parameterized biogeochemistry; –2.1 Pg C yr–1 for atmospheric inverse models; –1.9 Pg C yr–1 for global atmospheric constraints based on O2 / N2 ratios for 1990–2000; and –2.4 Pg C yr–1 for oceanic inverse models. An updated estimate of this anthropogenic CO2 flux based on a climatology of sea-air partial pressure of CO2 differences (ΔpCO2) (Takahashi et al., 2009) and a bulk formulation of gas transfer with wind speed for year 2000 is –2.0 Pg C yr–1. Using this ΔpCO2 climatology and empirical relationships of pCO2 with sea-surface temperature (SST) anomalies (Park et al., 2010a), the interannual variability of the contemporary CO2 flux is estimated to be 0.20 Pg C yr–1 (1σ) from 1990 through 2009. This is similar to the variability estimated by the OGCMs of 0.16 Pg C yr–1 but smaller than the interannual variability from atmospheric inverse estimates of 0.40 Pg C yr–1. The variability is largely driven by large-scale climate re-organizations. The decadal trends for different methods range from –0.13 (Pg C yr–1) decade–1 to –0.50 (Pg C yr−1) decade−1. The OGCMs and the data based sea-air CO2 flux estimates show smaller uptakes and appreciably smaller decadal trends than estimates based on changes in carbon inventory suggesting that methods capable of resolving shorter timescales are showing a slowing of the rate of ocean CO2 uptake. It is not clear if this large difference in trend is a methodological issue or a real natural feedback.