Monitoring
Global Carbon Budget 2021Background“Global Carbon Budget 2021” updates the budget to 2020 and projects 2021, analyzing the rebound of carbon dioxide (CO2) emissions after the initial downturn during the COVID-19 pandemic. Atmospheric CO2 continues to increase, with decadal mean growth reaching ~5.1 GtC yr⁻¹ for 2011–2020 and concentrations surpassing 412 ppm. Open access copy available |
Global Carbon Budget 2020Background“Global Carbon Budget 2020” quantifies the carbon dioxide (CO2) budget through 2019 and provides a 2020 projection, capturing the emissions drop associated with the COVID-19 pandemic. Atmospheric CO2 nevertheless continues to rise, reflecting the cumulative effect of past emissions and the fact that sinks absorb only part of the annual anthropogenic CO2. Open access copy available |
Global Carbon Budget 2019Background“Global Carbon Budget 2019” extends the budget series through 2018 with a 2019 projection, during a period of record-high emissions and intensifying policy focus on net-zero targets. Atmospheric CO2 continues to rise, crossing ~407 ppm in 2018, driven primarily by fossil fuel combustion with significant but smaller contributions from land-use change. This paper situates these trajectories within the industrial-era cumulative emissions that underpin IPCC remaining carbon budget assessments. Open access copy available |
Global Carbon Budget 2018Background“Global Carbon Budget 2018” extends the global carbon dioxide (CO2) budget through 2017 and provides a 2018 emissions projection, documenting a renewed acceleration in fossil emissions after a brief slowdown. Atmospheric CO2 reached 405.0 ± 0.1 ppm in 2017, reflecting cumulative industrial era emissions and ongoing dependence on fossil fuels and land-use change. The paper places these trends in the context of mitigation targets that depend on the magnitude of remaining carbon budgets. Open access copy available |
Global Carbon Budget 2017Background“Global Carbon Budget 2017” updates the evolving anthropogenic carbon dioxide (CO2) budget to 2016, capturing emissions growth, atmospheric accumulation, and sink responses in a period of strong climate policy debate. Atmospheric CO2 averaged about 402.8 ppm in 2016 and continues to rise as fossil fuel emissions remain the dominant anthropogenic CO2 source, with land-use change providing an additional contribution. The paper situates these changes within industrial-era cumulative emissions and increasing concerns about remaining carbon budgets. Open access copy available |
Global Carbon Budget 2016Background“Global Carbon Budget 2016” extends the budget through 2015 and provides preliminary 2016 fossil emission estimates, marking the period when global atmospheric carbon dioxide (CO2) surpassed 400 ppm. Atmospheric concentration increases from about 277 ppm in 1750 to 399.4 ± 0.1 ppm in 2015, with global monthly means above 400 ppm in multiple months. This study emphasizes that fossil fuel emissions remain the dominant anthropogenic source, while land-use change continues to contribute a smaller but persistent share. Open access copy available |
Global Carbon Budget 2015BackgroundThe "Global Carbon Budget 2015” updates the global CO2 budget through 2014, a year when atmospheric CO2 reached 397.15 ppm and monthly values exceeded 400 ppm for the first time globally. The assessment highlights the continued dominance of fossil fuel and industrial CO2 emissions, with land-use change remaining a significant but smaller source. It places these trends within the broader industrial era, with CO2 increasing from about 277 ppm in 1750, and ongoing growth in energy use and economic activity. Open access copy available |
Global carbon budget 2014Background“Global carbon budget 2014” details the development of human-caused carbon dioxide (CO2) emissions and how they are distributed among the atmosphere, ocean, and land up to 2013, with estimates for 2014. Atmospheric CO2 levels increased from about 277 ppm in 1750 to 395.31 ppm in 2013 and continue to rise as fossil fuel burning and land-use changes remain the main causes. This paper places these patterns within the context of industrial-era growth, international trade, and the differences between emerging and Annex B economies. Open access copy available |
Global carbon budget 2013Background“Global carbon budget 2013” updates the living carbon budget series through 2012, documenting continued growth in anthropogenic Carbon dioxide (CO2) emissions and atmospheric concentrations. Atmospheric CO2 rises from about 277 ppm in 1750 to 392.52 ± 0.10 ppm on average in 2012, with daily values exceeding 400 ppm at Mauna Loa in May 2013, symbolizing entry into a new high CO2 regime. The paper positions this trend against persistent fossil fuel dependence and ongoing land-use change, particularly deforestation. Open access copy available |
The global carbon budget 1959–2011Background“The global carbon budget 1959-2011” synthesizes more than five decades of anthropogenic Carbon dioxide (CO2) perturbations to the global carbon cycle, from early industrialization to contemporary high-emission conditions. It documents atmospheric CO2 increasing from about 278 ppm in 1750 to 391.31 ± 0.13 ppm by the end of 2011, with fossil fuel combustion replacing land-use change as the dominant source from around 1920. The paper frames these trends within persistent natural exchanges among atmosphere, ocean, and land, which are overlaid by human-driven emissions. Open access copy available |
