[1] Carbon dioxide (CO 2 ) fluxes from a network of 21 eddy covariance towers were upscaled to estimate the Alaskan CO 2 budget from 2000 to 2011 by combining satellite remote sensing data, disturbance information, and a support vector regression model. Data were compared with the CO 2 budget from an inverse model (CarbonTracker). Observed gross primary productivity (GPP), ecosystem respiration (RE), and net ecosystem exchange (NEE) were each well reproduced by the model on the site scale; root-mean-square errors (RMSEs) for GPP, RE, and NEE were 0.52, 0.23, and 0.48 g C m À2 d À1 , respectively. Landcover classification was the most important input for predicting GPP, whereas visible reflectance index of green ratio was the most important input for predicting RE. During the period of 2000-2011, predicted GPP and RE were 369 ± 22 and 362 ± 12 Tg C yr À1 (mean ± interannual variability) for Alaska, respectively, indicating an approximately neutral CO 2 budget for the decade. CarbonTracker also showed an approximately neutral CO 2 budget during 2000-2011 (growing season RMSE = 14 g C m À2 season À1 ; annual RMSE = 13 g C m À2 yr À1 ). Interannual CO 2 flux variability was positively correlated with air temperature anomalies from June to August, with Alaska acting as a greater CO 2 sink in warmer years. CO 2 flux trends for the decade were clear in disturbed ecosystems; positive trends in GPP and CO 2 sink were observed in areas where vegetation recovered for about 20 years after fire.