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1998
Staudigel, H, Albarede F, Blichert-Toft J, Edmond J, McDonough B, Jacobsen SB, Keeling R, Langmuir CH, Nielsen RL, Plank T, Rudnick R, Shaw HF, Shirey S, Veizer J, White W.  1998.  Geochemical Earth Reference Model (GERM): description of the initiative. Chemical Geology. 145:153-159.   10.1016/S0009-2541(97)00141-1   Abstract

The Geochemical Earth Reference Model (GERM) initiative is a grass root effort with the goals of establishing a community consensus on a chemical characterization of the Earth, its major reservoirs, and the flu?;es between them. The GERM initiative will provide a review of available scientific constraints for: (1) the composition of all major chemical reservoirs of the present-day Earth, from core to atmosphere; (2) present-day fluxes between reservoirs; (3) the Earth's chemical and isotopic evolution since accretion; and (4) the chemical and isotopic evolution of seawater as a record of global tectonics and climate, Even though most of the constraints for the GERM will be drawn from chemical data sets, some data will have to come from other disciplines, such as geophysics, nuclear physics, and cosmochemistry. GERM also includes a diverse chemical and physical data base and computer codes that are useful for our understanding of how the Earth works as a dynamic chemical and physical system. The GERM initiative is developed in an open community discussion on the World Wide Web (http://www-ep.es.llnl.gov/germ/germ-home.html) that is moderated by editors with responsibilities for different reservoirs, fluxes, data bases, and other scientific or technical aspects. These editors have agreed to lay out an initial, strawman GERM for their respective sections and to moderate community discussions leading to a first, preliminary consensus. The development of the GERM began with an initial workshop in Lyon, France in March, 1996. Since then, the GERM has continued to be developed on the Internet, punctuated by workshops and special sessions at professional meetings. A second GERM workshop will be held in La Jolla, CA USA on March 10-13, 1998. (C) 1998 Elsevier Science B.V. All nights reserved.

Keeling, RF, Stephens BB, Najjar RG, Doney SC, Archer D, Heimann M.  1998.  Seasonal variations in the atmospheric O2/N2 ratio in relation to the kinetics of air-sea gas exchange. Global Biogeochemical Cycles. 12:141-163.   10.1029/97gb02339   AbstractWebsite

Observations of seasonal variations in the atmospheric O-2/N-2 ratio are reported at nine baseline sites in the northern and southern hemispheres. Concurrent CO2 measurements are used to correct for the effects of land biotic exchanges of O-2 on the O-2/N-2 cycles thus allowing the residual component of the cycles due to oceanic exchanges of O-2 and N-2 to be calculated. The residual oceanic cycles in the northern hemisphere are nearly diametrically out of phase with the cycles in the southern hemisphere. The maxima in both hemispheres occur in summer. In both hemispheres, the middle-latitude sea level stations show the cycles with largest amplitudes and earliest phasing. Somewhat smaller amplitudes are observed at the high-latitude stations, and much smaller amplitudes are observed at the tropical stations. A model for simulating the oceanic component of the atmospheric O-2/N-2 cycles is presented consisting of the TM2 atmospheric tracer transport model [Heimann, 1995] driven at the lower boundary by O-2 fluxes derived from observed O-2 saturation anomalies in surface waters and by N-2 fluxes derived from the net air-sea heat flux. The model is optimized to fit the observed atmospheric O-2/N-2 cycles by adjusting the air-sea gas-exchange velocity, which relates O-2 anomaly to O-2 flux. The optimum fit corresponds to spatially and temporally averaged exchange velocities of 24+/-6 cm/hr for the oceans north of 31 degrees N and 29+/-12 cm/hr for the oceans south of 31 degrees S. These velocities agree to within the uncertainties with the gas-exchange velocities expected from the Wanninkhof [1992] formulation of the air-sea gas-exchange velocity combined with European Centre for Medium-Range Weather Forecasts winds [Gibson et al., 1997] but are larger than the exchange velocities expected from the Liss and Merlivat [1986] relation using the same winds. The results imply that the gas-exchange velocity for O-2, like that of CO2, may be enhanced in the open ocean by processes that were not systematically accounted for in the experiments used to derive the Liss and Merlivat relation.

2003
Le Quere, C, Aumont O, Bopp L, Bousquet P, Ciais P, Francey R, Heimann M, Keeling CD, Keeling RF, Kheshgi H, Peylin P, Piper SC, Prentice IC, Rayner PJ.  2003.  Two decades of ocean CO2 sink and variability. Tellus Series B-Chemical and Physical Meteorology. 55:649-656.   10.1034/j.1600-0889.2003.00043.x   AbstractWebsite

Atmospheric CO2 has increased at a nearly identical average rate of 3.3 and 3.2 Pg C yr(-1) for the decades of the 1980s and the 1990s, in spite of a large increase in fossil fuel emissions from 5.4 to 6.3 Pg C yr(-1). Thus, the sum of the ocean and land CO2 sinks was 1 Pg C yr(-1) larger in the 1990s than in to the 1980s. Here we quantify the ocean and land sinks for these two decades using recent atmospheric inversions and ocean models. The ocean and land sinks are estimated to be, respectively, 0.3 (0.1 to 0.6) and 0.7 (0.4 to 0.9) Pg C yr(-1) larger in the 1990s than in the 1980s. When variability less than 5 yr is removed, all estimates show a global oceanic sink more or less steadily increasing with time, and a large anomaly in the land sink during 1990-1994. For year-to-year variability, all estimates show 1/3 to 1/2 less variability in the ocean than on land, but the amplitude and phase of the oceanic variability remain poorly determined. A mean oceanic sink of 1.9 Pg C yr(-1) for the 1990s based on O-2 observations corrected for ocean outgassing is supported by these estimates, but an uncertainty on the mean value of the order of +/-0.7 Pg C yr(-1) remains. The difference between the two decades appears to be more robust than the absolute value of either of the two decades.

2004
Keeling, RF, Blaine T, Paplawsky B, Katz L, Atwood C, Brockwell T.  2004.  Measurement of changes in atmospheric Ar/N2 ratio using a rapid-switching, single-capillary mass spectrometer system. Tellus Series B-Chemical and Physical Meteorology. 56:322-338.   10.1111/j.1600-0889.2004.00117.x   AbstractWebsite

The atmospheric Ar/N-2 ratio is expected to undergo very slight variations due to exchanges of Ar and N-2 across the air-sea interface, driven by ocean solubility changes. Observations of these variations may provide useful constraints on large-scale fluxes of heat across the air-sea interface. A mass spectrometer system is described that incorporates a magnet with a wide exit face, allowing a large mass spread, and incorporates an inlet with rapid (5 s) switching of sources gases through a single capillary, thus achieving high precision in the comparison of sample and reference gases. The system allows simultaneous measurement of Ar/N-2, O-2/N, and CO2/N-2 ratios. The system achieves a short-term precision in Ar/N-2 of 10 per meg for a 10 s integration, which can be averaged to achieve an internal precision of a few per meg in the comparison of reference gases. Results for Ar/N-2 are reported from flasks samples collected from nine stations in a north-to-south global network over about a 1 yr period. The imprecision on an individual flask, as estimated from replicate agreement, is 11 per meg. This imprecision is dominated by real variability between samples at the time of analysis. Seasonal cycles are marginally resolved at the extra-tropical stations with amplitudes of 5 to 15 per meg. Annual-mean values are constant between stations to within 5 per meg. The results are compared with a numerical simulation of the cycles and gradients in Ar/N-2 based on the TM2 tracer transport model in combination with air-sea Ar and N-2 fluxes derived from climatological air-sea heat fluxes. The possibility is suggested that Ar/N-2 ratios may be detectably enriched near the ground by gravimetric or thermal fractionation under conditions of strong surface inversions.

2006
Adachi, Y, Kawamura K, Armi L, Keeling RF.  2006.  Diffusive separation of the lower atmosphere. Science (Washington). 311:1429-1429.: American Association for the Advancement of Science, 1200 New York Avenue, NW Washington DC 20005 USA, [mailto:membership@aaas.org], [URL:http://www.aaas.org]   10.1126/science.1121312   AbstractWebsite

The separation of atmospheric constituents by gravity has been proposed theoretically for almost two centuries. However, turbulent mixing has prevented the detection of this phenomenon in the lower atmosphere. By using precise measurements of the Ar/N2 ratio of air samples taken under strong nocturnal inversions, we have detected such separation in near-surface layers. The effect is shown to be consistent with combined influence of thermal and gravimetric separation, with the thermal contribution being more important.

Keeling, RF, Blaine T, Paplawsky B, Katz L, Atwood C, Brockwell T.  2006.  Measurement of changes in atmospheric Ar/N2 ratio using a rapid-switching, single-capillary mass spectrometer system (vol 56B, pg 322, 2006). Tellus Series B-Chemical and Physical Meteorology. 58:255-255.   10.1111/j.1600-0889.2006.00190.x   AbstractWebsite
n/a
2009
Reid, PC, Fischer AC, Lewis-Brown E, Meredith MP, Sparrow M, Andersson AJ, Antia A, Bates NR, Bathmann U, Beaugrand G, Brix H, Dye S, Edwards M, Furevik T, Gangsto R, Hatun H, Hopcroft RR, Kendall M, Kasten S, Keeling R, Le Quere C, Mackenzie FT, Malin G, Mauritzen C, Olafsson J, Paull C, Rignot E, Shimada K, Vogt M, Wallace C, Wang ZM, Washington R.  2009.  Impacts of the Oceans on Climate Change. Advances in Marine Biology. 56( Sims DW, Ed.).:1-150., San Diego: Elsevier Academic Press Inc   10.1016/s0065-2881(09)56001-4   Abstract

The oceans play a key role in climate regulation especially in part buffering (neutralising) the effects of increasing levels of greenhouse gases in the atmosphere and rising global temperatures. This chapter examines how the regulatory processes performed by the oceans alter as a response to climate change and assesses the extent to which positive feedbacks from the ocean may exacerbate climate change. There is clear evidence for rapid change in the oceans. As the main heat store for the world there has been an accelerating change in sea temperatures over the last few decades, which has contributed to rising sea-level. The oceans are also the main store of carbon dioxide (CO(2)), and are estimated to have taken up similar to 40% of anthropogenic-sourced CO(2) from the atmosphere since the beginning of the industrial revolution. A proportion of the carbon uptake is exported via the four ocean 'carbon pumps' (Solubility, Biological, Continental Shelf and Carbonate Counter) to the deep ocean reservoir. Increases in sea temperature and changing planktonic systems and ocean currents may lead to a reduction in the uptake of CO(2) by the ocean; some evidence suggests a suppression of parts of the marine carbon sink is already underway. While the oceans have buffered climate change through the uptake of CO(2) produced by fossil fuel burning this has already had an impact on ocean chemistry through ocean acidification and will continue to do so. Feedbacks to climate change from acidification may result from expected impacts on marine organisms (especially corals and calcareous plankton), ecosystems and biogeochemical cycles. The polar regions of the world are showing the most rapid responses to climate change. As a result of a strong ice-ocean influence, small changes in temperature, salinity and ice cover may trigger large and sudden changes in regional climate with potential downstream feedbacks to the climate of the rest of the world. A warming Arctic Ocean may lead to further releases of the potent greenhouse gas methane from hydrates and permafrost. The Southern Ocean plays a critical role in driving, modifying and regulating global climate change via the carbon cycle and through its impact on adjacent Antarctica. The Antarctic Peninsula has shown some of the most rapid rises in atmospheric and oceanic temperature in the world, with an associated retreat of the majority of glaciers. Parts of the West Antarctic ice sheet are deflating rapidly, very likely due to a change in the flux of oceanic heat to the undersides of the floating ice shelves. The final section on modelling feedbacks from the ocean to climate change identifies limitations and priorities for model development and associated observations. Considering the importance of the oceans to climate change and our limited understanding of climate-related ocean processes, our ability to measure the changes that are taking place are conspicuously inadequate. The chapter highlights the need for a comprehensive, adequately funded and globally extensive ocean observing system to be implemented and sustained as a high priority. Unless feedbacks from the oceans to climate change are adequately included in climate change models, it is possible that the mitigation actions needed to stabilise CO(2) and limit temperature rise over the next century will be underestimated.

2011
Welp, LR, Keeling RF, Meijer HAJ, Bollenbacher AF, Piper SC, Yoshimura K, Francey RJ, Allison CE, Wahlen M.  2011.  Interannual variability in the oxygen isotopes of atmospheric CO2 driven by El Nino. Nature. 477:579-582.   10.1038/nature10421   AbstractWebsite

The stable isotope ratios of atmospheric CO2 (O-18/O-16 and C-13/C-12) have been monitored since 1977 to improve our understanding of the global carbon cycle, because biosphere-atmosphere exchange fluxes affect the different atomic masses in a measurable way(1). Interpreting the O-18/O-16 variability has proved difficult, however, because oxygen isotopes in CO2 are influenced by both the carbon cycle and the water cycle(2). Previous attention focused on the decreasing O-18/O-16 ratio in the 1990s, observed by the global Cooperative Air Sampling Network of the US National Oceanic and Atmospheric Administration Earth System Research Laboratory. This decrease was attributed variously to a number of processes including an increase in Northern Hemisphere soil respiration(3); a global increase in C-4 crops at the expense of C-3 forests(4); and environmental conditions, such as atmospheric turbulence(5) and solar radiation(6), that affect CO2 exchange between leaves and the atmosphere. Here we present 30 years' worth of data on O-18/O-16 in CO2 from the Scripps Institution of Oceanography global flask network and show that the interannual variability is strongly related to the El Nino/Southern Oscillation. We suggest that the redistribution of moisture and rainfall in the tropics during an El Nino increases the O-18/O-16 ratio of precipitation and plant water, and that this signal is then passed on to atmospheric CO2 by biosphere-atmosphere gas exchange. We show how the decay time of the El Nino anomaly in this data set can be useful in constraining global gross primary production. Our analysis shows a rapid recovery from El Nino events, implying a shorter cycling time of CO2 with respect to the terrestrial biosphere and oceans than previously estimated. Our analysis suggests that current estimates of global gross primary production, of 120 petagrams of carbon per year(7), may be too low, and that a best guess of 150-175 petagrams of carbon per year better reflects the observed rapid cycling of CO2. Although still tentative, such a revision would present a new benchmark by which to evaluate global biospheric carbon cycling models.

2013
Miller, J, Lehman S, Wolak C, Turnbull J, Dunn G, Graven H, Keeling R, Meijer HAJ, Aerts-Bijma AT, Palstra SWL, Smith AM, Allison C, Southon J, Xu XM, Nakazawa T, Aoki S, Nakamura T, Guilderson T, LaFranchi B, Mukai H, Terao Y, Uchida M, Kondo M.  2013.  Initial results of an intercomparison of ams-based atmospheric (co2)-c-14 measurements. Radiocarbon. 55:1475-1483.   10.2458/azu_js_rc.55.16382   AbstractWebsite

This article presents results from the first 3 rounds of an international intercomparison of measurements of Delta(CO2)-C-14 in liter-scale samples of whole air by groups using accelerator mass spectrometry (AMS). The ultimate goal of the intercomparison is to allow the merging of Delta(CO2)-C-14 data from different groups, with the confidence that differences in the data are geophysical gradients and not artifacts of calibration. Eight groups have participated in at least 1 round of the intercomparison, which has so far included 3 rounds of air distribution between 2007 and 2010. The comparison is intended to be ongoing, so that: a) the community obtains a regular assessment of differences between laboratories; and b) individual laboratories can begin to assess the long-term repeatability of their measurements of the same source air. Air used in the intercomparison was compressed into 2 high-pressure cylinders in 2005 and 2006 at Niwot Ridge, Colorado (USA), with one of the tanks "spiked" with fossil CO2, so that the 2 tanks span the range of Delta(CO2)-C-14 typically encountered when measuring air from both remote background locations and polluted urban ones. Three groups show interlaboratory comparability within 1 parts per thousand for ambient level Delta(CO2)-C-14. For high CO2/low Delta(CO2)-C-14 air, 4 laboratories showed comparability within 2 parts per thousand. This approaches the goals set out by the World Meteorological Organization (WMO) CO2 Measurements Experts Group in 2005. One important observation is that single-sample precisions typically reported by the AMS community cannot always explain the observed differences within and between laboratories. This emphasizes the need to use long-term repeatability as a metric for measurement precision, especially in the context of long-term atmospheric monitoring.

2014
Rodgers, KB, Aumont O, Fletcher SEM, Plancherel Y, Bopp L, Montegut CD, Iudicone D, Keeling RF, Madec G, Wanninkhof R.  2014.  Strong sensitivity of Southern Ocean carbon uptake and nutrient cycling to wind stirring. Biogeosciences. 11:4077-4098.   10.5194/bg-11-4077-2014   AbstractWebsite

Here we test the hypothesis that winds have an important role in determining the rate of exchange of CO2 between the atmosphere and ocean through wind stirring over the Southern Ocean. This is tested with a sensitivity study using an ad hoc parameterization of wind stirring in an ocean carbon cycle model, where the objective is to identify the way in which perturbations to the vertical density structure of the planetary boundary in the ocean impacts the carbon cycle and ocean biogeochemistry. Wind stirring leads to reduced uptake of CO2 by the Southern Ocean over the period 2000-2006, with a relative reduction with wind stirring on the order of 0.9 Pg C yr(-1) over the region south of 45 degrees S. This impacts not only the mean carbon uptake, but also the phasing of the seasonal cycle of carbon and other ocean biogeochemical tracers. Enhanced wind stirring delays the seasonal onset of stratification, and this has large impacts on both entrainment and the biological pump. It is also found that there is a strong reduction on the order of 25-30% in the concentrations of NO3 exported in Subantarctic Mode Water (SAMW) to wind stirring. This finds expression not only locally over the Southern Ocean, but also over larger scales through the impact on advected nutrients. In summary, the large sensitivity identified with the ad hoc wind stirring parameterization offers support for the importance of wind stirring for global ocean biogeochemistry through its impact over the Southern Ocean.

Le Quere, C, Peters GP, Andres RJ, Andrew RM, Boden TA, Ciais P, Friedlingstein P, Houghton RA, Marland G, Moriarty R, Sitch S, Tans P, Arneth A, Arvanitis A, Bakker DCE, Bopp L, Canadell JG, Chini LP, Doney SC, Harper A, Harris I, House JI, Jain AK, Jones SD, Kato E, Keeling RF, Goldewijk KK, Kortzinger A, Koven C, Lefevre N, Maignan F, Omar A, Ono T, Park GH, Pfeil B, Poulter B, Raupach MR, Regnier P, Rodenbeck C, Saito S, Schwinger J, Segschneider J, Stocker BD, Takahashi T, Tilbrook B, van Heuven S, Viovy N, Wanninkhof R, Wiltshire A, Zaehle S.  2014.  Global carbon budget 2013. Earth System Science Data. 6:235-263.   10.5194/essd-6-235-2014   AbstractWebsite

Accurate assessment 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 development of climate policies, and project future climate change. Here we describe data sets and a methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates, consistency within and among components, alongside 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), mainly deforestation, are based on combined evidence from land-cover change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (G(ATM)) is computed from the annual changes in 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. The variability in SOCEAN is evaluated for the first time in this budget with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (S-LAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent dynamic global vegetation models forced by observed climate, CO2 and land cover change (some including nitrogen-carbon interactions). All uncertainties are reported as +/- 1 sigma, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2003-2012), E-FF was 8.6 +/- 0.4 GtC yr(-1), E-LUC 0.9 +/- 0.5 GtC yr(-1), G(ATM) 4.3 +/- 0.1 GtC yr(-1), S-OCEAN 2.5 +/- 0.5 GtC yr(-1), and S-LAND 2.8 +/- 0.8 GtC yr(-1). For year 2012 alone, E-FF grew to 9.7 +/- 0.5 GtC yr(-1), 2.2% above 2011, reflecting a continued growing trend in these emissions, GATM was 5.1 +/- 0.2 GtC yr(-1), S-OCEAN was 2.9 +/- 0.5 GtC yr(-1), and assuming an E-LUC of 1.0 +/- 0.5 GtC yr(-1) (based on the 2001-2010 average), S-LAND was 2.7 +/- 0.9 GtC yr(-1). G(ATM) was high in 2012 compared to the 2003-2012 average, almost entirely reflecting the high EFF. The global atmospheric CO2 concentration reached 392.52 +/- 0.10 ppm averaged over 2012. We estimate that E-FF will increase by 2.1% (1.1-3.1 %) to 9.9 +/- 0.5 GtC in 2013, 61% above emissions in 1990, based on projections of world gross domestic product and recent changes in the carbon intensity of the economy. With this projection, cumulative emissions of CO2 will reach about 535 +/- 55 GtC for 1870-2013, about 70% from E-FF (390 +/- 20 GtC) and 30% from E-LUC (145 +/- 50 GtC). This paper also documents any changes in the methods and data sets used in this new carbon budget from previous budgets (Le Quere et al., 2013). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi: 10.3334/CDIAC/GCP_2013_V2.3).

2015
Le Quere, C, Moriarty R, Andrew RM, Peters GP, Ciais P, Friedlingstein P, Jones SD, Sitch S, Tans P, Arneth A, Boden TA, Bopp L, Bozec Y, Canadell JG, Chini LP, Chevallier F, Cosca CE, Harris I, Hoppema M, Houghton RA, House JI, Jain AK, Johannessen T, Kato E, Keeling RF, Kitidis V, Goldewijk KK, Koven C, Landa CS, Landschutzer P, Lenton A, Lima ID, Marland G, Mathis JT, Metzl N, Nojiri Y, Olsen A, Ono T, Peng S, Peters W, Pfeil B, Poulter B, Raupach MR, Regnier P, Rodenbeck C, Saito S, Salisbury JE, Schuster U, Schwinger J, Seferian R, Segschneider J, Steinhoff T, Stocker BD, Sutton AJ, Takahashi T, Tilbrook B, van der Werf GR, Viovy N, Wang YP, Wanninkhof R, Wiltshire A, Zeng N.  2015.  Global carbon budget 2014. Earth System Science Data. 7:47-85.   10.5194/essd-7-47-2015   AbstractWebsite

Accurate assessment 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 development of climate policies, and project future climate change. Here we describe data sets and a methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics, and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates, consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil fuel combustion and cement production (E-FF) are based on energy statistics and cement production data, respectively, while emissions from land-use change (E-LUC), mainly deforestation, are based on combined evidence from land-cover-change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (G(ATM)) is computed from the annual changes in 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. The variability in S-OCEAN is evaluated with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (S-LAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent dynamic global vegetation models forced by observed climate, CO2, and land-cover-change (some including nitrogen-carbon interactions). We compare the mean land and ocean fluxes and their variability to estimates from three atmospheric inverse methods for three broad latitude bands. All uncertainties are reported as +/- 1 sigma, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2004-2013), E-FF was 8.9 +/- 0.4 GtC yr(-1), E-LUC 0.9 +/- 0.5 GtC yr(-1), G(ATM) 4.3 +/- 0.1 GtC yr(-1), S-OCEAN 2.6 +/- 0.5 GtC yr(-1), and S-LAND 2.9 +/- 0.8 GtC yr(-1). For year 2013 alone, E-FF grew to 9.9 +/- 0.5 GtC yr(-1), 2.3% above 2012, continuing the growth trend in these emissions, E-LUC was 0.9 +/- 0.5 GtC yr(-1), G(ATM) was 5.4 +/- 0.2 GtC yr(-1), S-OCEAN was 2.9 +/- 0.5 GtC yr(-1), and S-LAND was 2.5 +/- 0.9 GtC yr(-1). G(ATM) was high in 2013, reflecting a steady increase in E-FF and smaller and opposite changes between S-OCEAN and S-LAND compared to the past decade (2004-2013). The global atmospheric CO2 concentration reached 395.31 +/- 0.10 ppm averaged over 2013. We estimate that E-FF will increase by 2.5% (1.3-3.5 %) to 10.1 +/- 0.6 GtC in 2014 (37.0 +/- 2.2 GtCO(2) yr(-1)), 65% above emissions in 1990, based on projections of world gross domestic product and recent changes in the carbon intensity of the global economy. From this projection of E-FF and assumed constant E-LUC for 2014, cumulative emissions of CO2 will reach about 545 +/- 55 GtC (2000 +/- 200 GtCO(2)) for 1870-2014, about 75% from E-FF and 25% from E-LUC. This paper documents changes in the methods and data sets used in this new carbon budget compared with previous publications of this living data set (Le Quere et al., 2013, 2014). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi:10.3334/CDIAC/GCP_2014).

Le Quere, C, Moriarty R, Andrew RM, Canadell JG, Sitch S, Korsbakken JI, Friedlingstein P, Peters GP, Andres RJ, Boden TA, Houghton RA, House JI, Keeling RF, Tans P, Arneth A, Bakker DCE, Barbero L, Bopp L, Chang J, Chevallier F, Chini LP, Ciais P, Fader M, Feely RA, Gkritzalis T, Harris I, Hauck J, Ilyina T, Jain AK, Kato E, Kitidis V, Goldewijk KK, Koven C, Landschutzer P, Lauvset SK, Lefevre N, Lenton A, Lima ID, Metzl N, Millero F, Munro DR, Murata A, Nabel J, Nakaoka S, Nojiri Y, O'Brien K, Olsen A, Ono T, Perez FF, Pfeil B, Pierrot D, Poulter B, Rehder G, Rodenbeck C, Saito S, Schuster U, Schwinger J, Seferian R, Steinhoff T, Stocker BD, Sutton AJ, Takahashi T, Tilbrook B, van der Laan-Luijkx IT, van der Werf GR, van Heuven S, Vandemark D, Viovy N, Wiltshire A, Zaehle S, Zeng N.  2015.  Global Carbon Budget 2015. Earth System Science Data. 7:349-396.   10.5194/essd-7-349-2015   AbstractWebsite

Accurate assessment 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 development of climate policies, and project future climate change. Here we describe data sets and a methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics, and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates as well as consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil fuels and industry (E-FF) are based on energy statistics and cement production data, while emissions from land-use change (E-LUC), mainly deforestation, are based on combined evidence from land-cover-change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (G(ATM)) is computed from the annual changes in 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. The variability in S-OCEAN is evaluated with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (S-LAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent dynamic global vegetation models forced by observed climate, CO2, and land-cover change (some including nitrogen-carbon interactions). We compare the mean land and ocean fluxes and their variability to estimates from three atmospheric inverse methods for three broad latitude bands. All uncertainties are reported as +/- 1 sigma, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (20052014), E-FF was 9.0 +/- 0.5 GtC yr(-1) E-LUC was 0.9 +/- 0.5 GtC yr(-1), GATM was 4.4 +/- 0.1 GtC yr(-1), S-OCEAN was 2.6 +/- 0.5 GtC yr(-1), and S LAND was 3.0 +/- 0.8 GtC yr(-1). For the year 2014 alone, E FF grew to 9.8 +/- 0.5 GtC yr(-1), 0.6% above 2013, continuing the growth trend in these emissions, albeit at a slower rate compared to the average growth of 2.2% yr(-1) that took place during 2005-2014. Also, for 2014, E-LUC was 1.1 +/- 0.5 GtC yr(-1), G(ATM) was 3.9 +/- 0.2 GtC yr(-1), S-OCEAN was 2.9 +/- 0.5 GtC yr(-1), and S-LAND was 4.1 +/- 0.9 GtC yr(-1). G(ATM) was lower in 2014 compared to the past decade (2005-2014), reflecting a larger S-LAND for that year. The global atmospheric CO2 concentration reached 397.15 +/- 0.10 ppm averaged over 2014. For 2015, preliminary data indicate that the growth in E-FF will be near or slightly below zero, with a projection of 0.6 [ range of 1.6 to C 0.5] %, based on national emissions projections for China and the USA, and projections of gross domestic product corrected for recent changes in the carbon intensity of the global economy for the rest of the world. From this projection of E-FF and assumed constant E LUC for 2015, cumulative emissions of CO2 will reach about 555 +/- 55 GtC (2035 +/- 205 GtCO(2)) for 1870-2015, about 75% from E FF and 25% from E LUC. This living data update documents changes in the methods and data sets used in this new carbon budget compared with previous publications of this data set (Le Quere et al., 2015, 2014, 2013). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi: 10.3334/CDIAC/GCP_2015).

2016
Jeong, SG, Newman S, Zhang JS, Andrews AE, Bianco L, Bagley J, Cui XG, Graven H, Kim J, Salameh P, LaFranchi BW, Priest C, Campos-Pineda M, Novakovskaia E, Sloop CD, Michelsen HA, Bambha RP, Weiss RF, Keeling R, Fischer ML.  2016.  Estimating methane emissions in California's urban and rural regions using multitower observations. Journal of Geophysical Research-Atmospheres. 121:13031-13049.   10.1002/2016jd025404   AbstractWebsite

We present an analysis of methane (CH4) emissions using atmospheric observations from 13 sites in California during June 2013 to May 2014. A hierarchical Bayesian inversion method is used to estimate CH4 emissions for spatial regions (0.3 degrees pixels for major regions) by comparing measured CH4 mixing ratios with transport model (Weather Research and Forecasting and Stochastic Time-Inverted Lagrangian Transport) predictions based on seasonally varying California-specific CH4 prior emission models. The transport model is assessed using a combination of meteorological and carbon monoxide (CO) measurements coupled with the gridded California Air Resources Board (CARB) CO emission inventory. The hierarchical Bayesian inversion suggests that state annual anthropogenic CH4 emissions are 2.42 +/- 0.49 Tg CH4/yr (at 95% confidence), higher (1.2-1.8 times) than the current CARB inventory (1.64 Tg CH4/yr in 2013). It should be noted that undiagnosed sources of errors or uncaptured errors in the model-measurement mismatch covariance may increase these uncertainty bounds beyond that indicated here. The CH4 emissions from the Central Valley and urban regions (San Francisco Bay and South Coast Air Basins) account for similar to 58% and 26% of the total posterior emissions, respectively. This study suggests that the livestock sector is likely the major contributor to the state total CH4 emissions, in agreement with CARB's inventory. Attribution to source sectors for subregions of California using additional trace gas species would further improve the quantification of California's CH4 emissions and mitigation efforts toward the California Global Warming Solutions Act of 2006 (Assembly Bill 32).

Le Quere, C, Andrew RM, Canadell JG, Sitch S, Korsbakken JI, Peters GP, Manning AC, Boden TA, Tans PP, Houghton RA, Keeling RF, Alin S, Andrews OD, Anthoni P, Barbero L, Bopp L, Chevallier F, Chini LP, Ciais P, Currie K, Delire C, Doney SC, Friedlingstein P, Gkritzalis T, Harris I, Hauck J, Haverd V, Hoppema M, Goldewijk KK, Jain AK, Kato E, Kortzinger A, Landschutzer P, Lefevre N, Lenton A, Lienert S, Lombardozzi D, Melton JR, Metzl N, Millero F, Monteiro PMS, Munro DR, Nabel J, Nakaoka S, O'Brien K, Olsen A, Omar AM, Ono T, Pierrot D, Poulter B, Rodenbeck C, Salisbury J, Schuster U, Schwinger J, Seferian R, Skjelvan I, Stocker BD, Sutton AJ, Takahashi T, Tian HQ, Tilbrook B, van der Laan-Luijkx IT, van der Werf GR, Viovy N, Walker AP, Wiltshire AJ, Zaehle S.  2016.  Global Carbon Budget 2016. Earth System Science Data. 8:605-649.   10.5194/essd-8-605-2016   AbstractWebsite

Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere - the "global carbon budget" - is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe data sets and methodology to quantify all major components of the global carbon budget, including their uncertainties, based on the combination of a range of data, algorithms, statistics, and model estimates and their interpretation by a broad scientific community. We discuss changes compared to previous estimates and consistency within and among components, alongside methodology and data limitations. CO2 emissions from fossil fuels and industry (E-FF) are based on energy statistics and cement production data, respectively, while emissions from land-use change (E-LUC), mainly deforestation, are based on combined evidence from land-cover change data, fire activity associated with deforestation, and models. The global atmospheric CO2 concentration is measured directly and its rate of growth (G(ATM)) is computed from the annual changes in 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. The variability in S-OCEAN is evaluated with data products based on surveys of ocean CO2 measurements. The global residual terrestrial CO2 sink (S-LAND) is estimated by the difference of the other terms of the global carbon budget and compared to results of independent dynamic global vegetation models. We compare the mean land and ocean fluxes and their variability to estimates from three atmospheric inverse methods for three broad latitude bands. All uncertainties are reported as +/- 1 sigma, reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2006-2015), E-FF was 9.3 +/- 0.5 GtC yr(-1), E-LUC 1.0 +/- 0.5 GtC yr(-1), G(ATM) 4.5 +/- 0.1 GtC yr(-1), S-OCEAN 2.6 +/- 0.5 GtC yr(-1), and S-LAND 3.1 +/- 0.9 GtC yr(-1). For year 2015 alone, the growth in E-FF was approximately zero and emissions remained at 9.9 +/- 0.5 GtC yr(-1), showing a slowdown in growth of these emissions compared to the average growth of 1.8% yr(-1) that took place during 2006-2015. Also, for 2015, E-LUC was 1.3 +/- 0.5 GtC yr(-1), G(ATM) was 6.3 +/- 0.2 GtC yr(-1), S-OCEAN was 3.0 +/- 0.5 GtC yr(-1), and S-LAND was 1.9 +/- 0.9 GtC yr(-1). G(ATM) was higher in 2015 compared to the past decade (2006-2015), reflecting a smaller S-LAND for that year. The global atmospheric CO2 concentration reached 399.4 +/- 0.1 ppm averaged over 2015. For 2016, preliminary data indicate the continuation of low growth in E-FF with +0.2% (range of -1.0 to +1.8 %) based on national emissions projections for China and USA, and projections of gross domestic product corrected for recent changes in the carbon intensity of the economy for the rest of the world. In spite of the low growth of E-FF in 2016, the growth rate in atmospheric CO2 concentration is expected to be relatively high because of the persistence of the smaller residual terrestrial sink (S-LAND) in response to El Nino conditions of 2015-2016. From this projection of E-FF and assumed constant E-LUC for 2016, cumulative emissions of CO2 will reach 565 +/- 55 GtC (2075 +/- 205 GtCO(2)) for 1870-2016, about 75% from E-FF and 25% from E-LUC. This living data update documents changes in the methods and data sets used in this new carbon budget compared with previous publications of this data set (Le Quere et al., 2015b, a, 2014, 2013). All observations presented here can be downloaded from the Carbon Dioxide Information Analysis Center (doi: 10.3334/CDIAC/GCP_2016).

2017
Graven, H, Allison CE, Etheridge DM, Hammer S, Keeling RF, Levin I, Meijer HAJ, Rubino M, Tans PP, Trudinger CM, Vaughn BH, White JWC.  2017.  Compiled records of carbon isotopes in atmospheric CO2 for historical simulations in CMIP6. Geoscientific Model Development. 10:4405-4417.   10.5194/gmd-10-4405-2017   AbstractWebsite

The isotopic composition of carbon (Delta C-14 and delta C-13) in atmospheric CO2 and in oceanic and terrestrial carbon reservoirs is influenced by anthropogenic emissions and by natural carbon exchanges, which can respond to and drive changes in climate. Simulations of C-14 and C-13 in the ocean and terrestrial components of Earth system models (ESMs) present opportunities for model evaluation and for investigation of carbon cycling, including anthropogenic CO2 emissions and uptake. The use of carbon isotopes in novel evaluation of the ESMs' component ocean and terrestrial biosphere models and in new analyses of historical changes may improve predictions of future changes in the carbon cycle and climate system. We compile existing data to produce records of Delta C-14 and delta C-13 in atmospheric CO2 for the historical period 1850-2015. The primary motivation for this compilation is to provide the atmospheric boundary condition for historical simulations in the Coupled Model Intercomparison Project 6 (CMIP6) for models simulating carbon isotopes in the ocean or terrestrial biosphere. The data may also be useful for other carbon cycle modelling activities.

2018
Stephens, BB, Long MC, Keeling RF, Kort EA, Sweeney C, Apel EC, Atlas EL, Beaton S, Bent JD, Blake NJ, Bresch JF, Casey J, Daube BC, Diao MH, Diaz E, Dierssen H, Donets V, Gao BC, Gierach M, Green R, Haag J, Hayman M, Hills AJ, Hoecker-Martinez MS, Honomichl SB, Hornbrook RS, Jensen JB, Li RR, McCubbin I, McKain K, Morgan EJ, Nolte S, Powers JG, Rainwater B, Randolph K, Reeves M, Schauffler SM, Smith K, Smith M, Stith J, Stossmeister G, Toohey DW, Watt AS.  2018.  The O-2/N-2 Ratio and CO2 Airborne Southern Ocean Study. Bulletin of the American Meteorological Society. 99:381-402.   10.1175/bams-d-16-0206.1   AbstractWebsite

The Southern Ocean plays a critical role in the global climate system by mediating atmosphere-ocean partitioning of heat and carbon dioxide. However, Earth system models are demonstrably deficient in the Southern Ocean, leading to large uncertainties in future air-sea CO2 flux projections under climate warming and incomplete interpretations of natural variability on interannual to geologic time scales. Here, we describe a recent aircraft observational campaign, the O-2/N-2 Ratio and CO2 Airborne Southern Ocean (ORCAS) study, which collected measurements over the Southern Ocean during January and February 2016. The primary research objective of the ORCAS campaign was to improve observational constraints on the seasonal exchange of atmospheric carbon dioxide and oxygen with the Southern Ocean. The campaign also included measurements of anthropogenic and marine biogenic reactive gases; high-resolution, hyperspectral ocean color imaging of the ocean surface; and microphysical data relevant for understanding and modeling cloud processes. In each of these components of the ORCAS project, the campaign has significantly expanded the amount of observational data available for this remote region. Ongoing research based on these observations will contribute to advancing our understanding of this climatically important system across a range of topics including carbon cycling, atmospheric chemistry and transport, and cloud physics. This article presents an overview of the scientific and methodological aspects of the ORCAS project and highlights early findings.

Le Quere, C, Andrew RM, Friedlingstein P, Sitch S, Pongratz J, Manning AC, Korsbakken JI, Peters GP, Canadell JG, Jackson RB, Boden TA, Tans PP, Andrews OD, Arora VK, Bakker DCE, Barbero L, Becker M, Betts RA, Bopp L, Chevallier F, Chini LP, Ciais P, Cosca CE, Cross J, Currie K, Gasser T, Harris I, Hauck J, Haverd V, Houghton RA, Hunt CW, Hurtt G, Ilyina T, Jain AK, Kato E, Kautz M, Keeling RF, Goldewijk KK, Kortzinger A, Landschutzer P, Lefevre N, Lenton A, Lienert S, Lima I, Lombardozzi D, Metzl N, Millero F, Monteiro PMS, Munro DR, Nabel J, Nakaoka S, Nojiri Y, Padin XA, Peregon A, Pfeil B, Pierrot D, Poulter B, Rehder G, Reimer J, Rodenbeck C, Schwinger J, Seferian R, Skjelvan I, Stocker BD, Tian HQ, Tilbrook B, Tubiello FN, van der Laan-Luijkx IT, van der Werf GR, van Heuven S, Viovy N, Vuichard N, Walker AP, Watson AJ, Wiltshire AJ, Zaehle S, Zhu D.  2018.  Global Carbon Budget 2017. Earth System Science Data. 10:405-448.   10.5194/essd-10-405-2018   AbstractWebsite

Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere - the "global carbon budget" - is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties. CO2 emissions from fossil fuels and industry (E-FF) are based on energy statistics and cement production data, respectively, while emissions from land-use change (E-LUC), mainly deforestation, are based on land-cover change data and bookkeeping models. The global atmospheric CO2 concentration is measured directly and its rate of growth (G(ATM)) is computed from the annual changes in concentration. The ocean CO2 sink (S-OCEAN) and terrestrial CO2 sink (S-LAND) are estimated with global process models constrained by observations. The resulting carbon budget imbalance (B-IM), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and understanding of the contemporary carbon cycle. All uncertainties are reported as +/- 1 sigma. For the last decade available (2007-2016), E-FF was 9.4 +/- 0.5 GtC yr(-1), E-LUC 1.3 +/- 0.7 GtC yr(-1), G(ATM) 4.7 +/- 0.1 GtC yr(-1), S-OCEAN 2.4 +/- 0.5 GtC yr(-1), and S-LAND 3.0 +/- 0.8 GtC yr(-1), with a budget imbalance B-IM of 0.6 GtC yr(-1) indicating overestimated emissions and/or underestimated sinks. For year 2016 alone, the growth in E-FF was approximately zero and emissions remained at 9.9 +/- 0.5 GtC yr(-1). Also for 2016, E-LUC was 1.3 +/- 0.7 GtC yr(-1), G(ATM) was 6.1 +/- 0.2 GtC yr(-1), S-OCEAN was 2.6 +/- 0.5 GtC yr(-1), and S-LAND was 2.7 +/- 1.0 GtC yr(-1), with a small B-IM of 0.3 GtC. G(ATM) continued to be higher in 2016 compared to the past decade (2007-2016), reflecting in part the high fossil emissions and the small S-LAND consistent with El Nino conditions. The global atmospheric CO2 concentration reached 402.8 +/- 0.1 ppm averaged over 2016. For 2017, preliminary data for the first 6-9 months indicate a renewed growth in E-FF of +2.0% (range of 0.8 to 3.0 %) based on national emissions projections for China, USA, and India, and projections of gross domestic product (GDP) corrected for recent changes in the carbon intensity of the economy for the rest of the world. This living data update documents changes in the methods and data sets used in this new global carbon budget compared with previous publications of this data set (Le Quere et al., 2016, 2015b, a, 2014, 2013). All results presented here can be downloaded from https://doi.org/10.18160/GCP-2017 (GCP, 2017).

Betts, RA, Jones CD, Knight JR, Keeling RF, Kennedy JJ, Wiltshire AJ, Andrew RM, Aragao L.  2018.  A successful prediction of the record CO2 rise associated with the 2015/2016 El Nino. Philosophical Transactions of the Royal Society B-Biological Sciences. 373   10.1098/rstb.2017.0301   AbstractWebsite

In early 2016, we predicted that the annual rise in carbon dioxide concentration at Mauna Loa would be the largest on record. Our forecast used a statistical relationship between observed and forecast sea surface temperatures in the Nino 3.4 region and the annual CO2 rise. Here, we provide a formal verification of that forecast. The observed rise of 3.4 ppm relative to 2015 was within the forecast range of 3.15 +/- 0.53 ppm, so the prediction was successful. A global terrestrial biosphere model supports the expectation that the El Nino weakened the tropical land carbon sink. We estimate that the El Nino contributed approximately 25% to the record rise in CO2, with 75% due to anthropogenic emissions. The 2015/2016 CO2 rise was greater than that following the previous large El Nino in 1997/1998, because anthropogenic emissions had increased. We had also correctly predicted that 2016 would be the first year with monthly mean CO2 above 400 ppm all year round. We now estimate that atmospheric CO2 at Mauna Loa would have remained above 400 ppm all year round in 2016 even if the El Nino had not occurred, contrary to our previous expectations based on a simple extrapolation of previous trends. This article is part of a discussion meeting issue 'The impact of the 2015/2016 El Nino on the terrestrial tropical carbon cycle: patterns, mechanisms and implications'.

Le Quere, C, Andrew RM, Friedlingstein P, Sitch S, Hauck J, Pongratz J, Pickers PA, Korsbakken JI, Peters GP, Canadell JG, Arneth A, Arora VK, Barbero L, Bastos A, Bopp L, Chevallier F, Chini LP, Ciais P, Doney SC, Gkritzalis T, Goll DS, Harris I, Haverd V, Hoffman FM, Hoppema M, Houghton RA, Hurtt G, Ilyina T, Jain AK, Johannessen T, Jones CD, Kato E, Keeling RF, Goldewijk KK, Landschutzer P, Lefevre N, Lienert S, Liu Z, Lombardozzi D, Metzl N, Munro DR, Nabel J, Nakaoka S, Neill C, Olsen A, Ono T, Patra P, Peregon A, Peters W, Peylin P, Pfeil B, Pierrot D, Poulter B, Rehder G, Resplandy L, Robertson E, Rocher M, Rodenbeck C, Schuster U, Schwinger J, Seferian R, Skjelvan I, Steinhoff T, Sutton A, Tans PP, Tian HQ, Tilbrook B, Tubiello FN, van der Laan-Luijkx IT, van der Werf GR, Viovy N, Walker AP, Wiltshire AJ, Wright R, Zaehle S, Zheng B.  2018.  Global Carbon Budget 2018. Earth System Science Data. 10:2141-2194.   10.5194/essd-10-2141-2018   AbstractWebsite

Accurate assessment of anthropogenic carbon dioxide (CO2) emissions and their redistribution among the atmosphere, ocean, and terrestrial biosphere - the "global carbon budget" - is important to better understand the global carbon cycle, support the development of climate policies, and project future climate change. Here we describe data sets and methodology to quantify the five major components of the global carbon budget and their uncertainties. Fossil CO2 emissions (E-FF) are based on energy statistics and cement production data, while emissions from land use and land-use change (E-LUC), mainly deforestation, are based on land use and land -use change data and bookkeeping models. Atmospheric CO2 concentration is measured directly and its growth rate (G(ATM)) is computed from the annual changes in concentration. The ocean CO2 sink (S-OCEAN) and terrestrial CO2 sink (S-LAND) are estimated with global process models constrained by observations. The resulting carbon budget imbalance (B-IM), the difference between the estimated total emissions and the estimated changes in the atmosphere, ocean, and terrestrial biosphere, is a measure of imperfect data and understanding of the contemporary carbon cycle. All uncertainties are reported as +/- 1 sigma. For the last decade available (2008-2017), E-FF was 9.4 +/- 0.5 GtC yr(-1), E-LUC 1.5 +/- 0.7 GtC yr(-1), G(ATM) 4.7 +/- 0.02 GtC yr(-1), S-OCEAN 2.4 +/- 0.5 GtC yr(-1), and S-LAND 3.2 +/- 0.8 GtC yr(-1), with a budget imbalance B-IM of 0.5 GtC yr(-1) indicating overestimated emissions and/or underestimated sinks. For the year 2017 alone, the growth in E-FF was about 1.6 % and emissions increased to 9.9 +/- 0.5 GtC yr(-1). Also for 2017, E-LUC was 1.4 +/- 0.7 GtC yr(-1), G(ATM) was 4.6 +/- 0.2 GtC yr(-1), S-OCEAN was 2.5 +/- 0.5 GtC yr(-1), and S-LAND was 3.8 +/- 0.8 GtC yr(-1), with a B-IM of 0.3 GtC. The global atmospheric CO2 concentration reached 405.0 +/- 0.1 ppm averaged over 2017. For 2018, preliminary data for the first 6-9 months indicate a renewed growth in E-FF of +2.7 % (range of 1.8 % to 3.7 %) based on national emission projections for China, the US, the EU, and India and projections of gross domestic product corrected for recent changes in the carbon intensity of the economy for the rest of the world. The analysis presented here shows that the mean and trend in the five components of the global carbon budget are consistently estimated over the period of 1959-2017, but discrepancies of up to 1 GtC yr(-1) persist for the representation of semi-decadal variability in CO2 fluxes. A detailed comparison among individual estimates and the introduction of a broad range of observations show (1) no consensus in the mean and trend in land -use change emissions, (2) a persistent low agreement among the different methods on the magnitude of the land CO2 flux in the northern extra-tropics, and (3) an apparent underestimation of the CO2 variability by ocean models, originating outside the tropics. This living data update documents changes in the methods and data sets used in this new global carbon budget and the progress in understanding the global carbon cycle compared with previous publications of this data set (Le Quere et al., 2018, 2016, 2015a, b, 2014, 2013). All results presented here can be downloaded from https://doi.org/10.18160/GCP-2018.