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Accurate assessments of anthropogenic carbon dioxide (CO₂) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere is important to better understand the global carbon cycle, support the climate policy process, and project future climate change. Present-day analysis requires the combination of a range of data, algorithms, statistics and model estimates and their interpretation by a broad scientific community. Here we describe datasets and a methodology developed by the global carbon cycle science community to quantify all major components of the global carbon budget, including their uncertainties. We discuss changes compared to previous estimates, consistency within and among components, and methodology and data limitations. CO₂ emissions from fossil fuel combustion and cement production (E_FF) are based on energy statistics, while emissions from Land-Use Change (E_LUC), including deforestation, are based on combined evidence from land cover change data, fire activity in regions undergoing deforestation, and models. The global atmospheric CO₂ concentration is measured directly and its rate of growth (G_ATM) is computed from the concentration. The mean ocean CO₂ sink (S_OCEAN) is based on observations from the 1990s, while the annual anomalies and trends are estimated with ocean models. Finally, the global residual terrestrial CO₂ sink (S_LAND) is estimated by the difference of the other terms. For the last decade available (2002–2011), E_FF was 8.3 ± 0.4 PgC yr⁻¹, E_LUC 1.0 ± 0.5 PgC yr⁻¹, G_ATM 4.3 ± 0.1 PgC yr⁻¹, S_OCEAN 2.5 ± 0.5 PgC yr⁻¹, and S_LAND 2.6 ± 0.8 PgC yr⁻¹ …