Global Carbon Budget 2015

Abstract

Abstract. Accurate assessment of anthropogenic carbon dioxide (CO 2 ) 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. CO 2 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 CO 2 concentration is measured directly and its rate of growth (G ATM ) is computed from the annual changes in concentration. The mean ocean CO 2 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 CO 2 measurements. The global residual terrestrial CO 2 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, CO 2 , 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 ±1σ , reflecting the current capacity to characterise the annual estimates of each component of the global carbon budget. For the last decade available (2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014), E FF was 9.0 ± 0.5 GtC yr −1 , E LUC was 0.9 ± 0.5 GtC yr −1 , G ATM 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)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013)(2014), reflecting a larger S LAND for that year. The global atmospheric CO 2 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 +0....

Catalytic activity of hydrotalcite-derived catalysts in the dry reforming of methane: on the effect of Ce promotion and feed gas composition

“…Despite the trend to limit emissions of carbon dioxide to the environment ongoing for many years, the amount of CO 2 emitted from human activities had increased from 35 billion tons in 2008 [1] to 35.9 billion tons in 2014 [2]. This shows that the reduction of CO 2 emission is still an unsolved problem.…”

Climate-driven disturbances in the San Juan River sub-basin of the Colorado River

“…We selected the four ESMs from CMIP5 because they implemented dynamic vegetation processes: HadGEM2-ES (Collins et al, 2011;Cox, 2001), MIROC-ESM (SIEB-DGVM; Watanabe et al, 2011;Sato et al, 2007), MPI-ESM-LR (JSBACH; Giorgetta et al, 2013;Reick et al, 2013), and IPSL-CM5B-LR (ORCHIDEE; Krinner et al, 2005). We used the representative concentration pathway (RCP) 8.5 emissions scenario, which stipulates strongly increasing emissions by 2100 (Van Vuuren et al, 2011) and corroborates current emissions on par with RCP 8.5 (Le Quéré et al, 2015).…”

Transient dynamics of terrestrial carbon storage: mathematical foundation and its applications

“…Without land C sequestration, the atmospheric CO 2 concentration would have increased by an additional 95 parts per million and resulted in more climate warming (Le Quéré et al, 2015). During 1 decade from 2005 to 2014, terrestrial ecosystems sequestrated 3 ± 0.8 Gt C year −1 (Le Quéré et al, 2015), which would cost 1 billion dollars if the equivalent amount of C was sequestrated using C capture and storage techniques . Thus, terrestrial ecosystems effectively mitigate global change through natural processes with minimal cost.…”

“…Cumulatively, land ecosystems have sequestered more than 160 Gt C from 1750 to 2015 (Le Quéré et al, 2015). Without land C sequestration, the atmospheric CO 2 concentration would have increased by an additional 95 parts per million and resulted in more climate warming (Le Quéré et al, 2015).…”

“…Cumulatively, land ecosystems have sequestered more than 160 Gt C from 1750 to 2015 (Le Quéré et al, 2015). Without land C sequestration, the atmospheric CO 2 concentration would have increased by an additional 95 parts per million and resulted in more climate warming (Le Quéré et al, 2015). During 1 decade from 2005 to 2014, terrestrial ecosystems sequestrated 3 ± 0.8 Gt C year −1 (Le Quéré et al, 2015), which would cost 1 billion dollars if the equivalent amount of C was sequestrated using C capture and storage techniques .…”