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Analysis: Global CO2 Emissions Set to Rise 2% in 2017 After Three-Year ‘Plateau’
By Zeke Hausfather
Over the past three years, global CO2 emissions from fossil fuels have remained relatively flat. However, early estimates from the Global Carbon Project (GCP) using preliminary data suggest that this is likely to change in 2017 with global emissions set to grow by around two percent, albeit with some uncertainties.
Hopes that global emissions had peaked during the past three years were likely premature. However, GCP researchers say that global emissions are unlikely to return to the high growth rates seen during the 2000s. They argue that it is more likely that emissions over the next few years will plateau or only grow slightly, as countries implement their commitments under the Paris agreement.
2017 emissions likely to increase
The GCP is a group of international researchers who assess both sources and sinks of carbon. It has published an annual global carbon budget report since 2006. Its newly released global carbon budget for 2017 provides estimates of emissions by country, global emissions from land-use changes, atmospheric accumulation of CO2, and absorption of carbon from the atmosphere by the land and oceans.
The figure below shows global CO2 emissions from fossil fuels, divided into emissions from China (red shading), India (yellow), the U.S. (bright blue), EU (dark blue) and the remainder of the world (grey). After a rapid increase in global emissions of around three percent per year between 2000 and 2013, emissions only grew by 0.4 percent per year between 2013 and 2016.
Annual CO2 emissions from fossil fuels by major country and rest of world from 1959-2017, in gigatons CO2 per year (GtCO2). Note that 2017 numbers are preliminary estimates. Data from the Global Carbon Project and available here. Chart by Carbon Brief using Highcharts.
Much of the slowdown in the growth of global emissions in recent years has been driven by a combination of reductions in the U.S. and China, as well as relatively little growth in emissions in other countries. This changed in 2017, with little-to-no reductions in U.S. emissions and a sizable increase in Chinese emissions.
India's emissions increased a bit more slowly in 2017 than in the past few years, while the EU's emissions have remained relatively flat since 2014 and did not noticeably change in 2017. The growth in emissions from 2016 to 2017 also more than doubled in the rest of the world.
The total emissions for each year between 2014 and 2017 and the countries that were responsible for the change in emissions are shown in the figure below. Annual emissions for 2014, 2015, 2016 and estimates for 2017 are shown by the black bars. The colored bars show the change in emissions between each set of years, broken down by country. Negative values show reductions in emissions, while positive values reflect emission increases.
Annual global CO2 emissions from fossil fuels (black bars) and drivers of changes between years by country (colored bars). Negative values indicate reductions in emissions. Data from the Global Carbon Project. Chart by Carbon Brief using Highcharts.
As 2017 is not yet over—and somewhat limited data is available—these projections are still subject to large uncertainties. The global estimate of a two percent increase in emissions could be as low as 0.8 percent or as high as three percent, the researchers said. The GCP will publish more complete 2017 numbers in early 2018 when all the data is available.
The GCP reported that China's emissions are projected to grow by 3.5 percent in 2017, with wide uncertainty ranging from 0.7 percent to 5.4 percent. China represents the single most important reason for the resumption of global emissions growth in 2017. This is driven by a projected three percent increase in coal consumption, 12 percent increase in natural gas consumption and five percent increase in oil consumption.
While the past few years have seen similar increases in natural gas and oil consumption in China, 2017 will reverse a few years of flat or declining coal consumption. The GCP reports that the 2017 increase in coal consumption—and, in turn, overall Chinese emissions—is driven by a combination in increased industrial production and reduced hydroelectric generation associated with lower-than-usual rainfall.
However, industrial growth has started to slow down again over the past three months, which might signal slower emissions growth and coal consumption in 2018.
The best estimate of 2017 U.S. emissions is for a decline of about 0.4 percent, though they could decrease by as much as 2.7 percent or increase by as much as 1.9 percent. This will likely be a smaller decrease than in past years, as U.S. emissions have declined by around 1.2 percent per year over the past decade. This reflects a modest uptick in coal use for electricity generation in the U.S. and an associated decline in gas use. 2017 will likely be the first time in the past five years that U.S. coal consumption has risen.
India's emissions are projected to grow by two percent in 2017 (ranging from 0.2 percent to 3.8 percent), lower than, on average, the six percent growth in emissions over the past decade. This appears to be mostly due to reduced oil consumption growth and a six percent reduction in cement production. Coal consumption increased at a similar rate to prior years.
Global carbon budget
Every year the GCP provides an estimate of the global carbon budget, which estimates both the release and uptake of carbon including emissions from fossil fuels and industry, emissions from land-use changes, carbon taken up by the oceans and land, and changes in atmospheric concentrations of CO2. This differs from the commonly used term "carbon budget," referring to how much emissions are left to meet a climate target, such as avoiding 2°C warming.
The most recent budget, including estimated values for 2017, is shown in the figure below. Values above zero represent sources of CO2—from fossil fuels and land use—while values below zero represent sinks of CO2, where the sources of CO2 end up. CO2 emissions either accumulate in the atmosphere, or are absorbed by the oceans or land vegetation.
Annual global carbon budget of sources and sinks from 1959-2017. Note that the budget does not fully balance every year due to remaining uncertainties, particularly in sinks. Note that 2017 numbers are preliminary estimates. Data from the Global Carbon Project and available here. Chart by Carbon Brief using Highcharts.
Land-use changes, such as deforestation and fires, comprised 11 percent of total emissions in 2017, marginally down from the 13 percent average over the past decade. The remaining 89 percent of emissions came from fossil fuels and industry. Total CO2 emissions decreased by about two percent between 2015 and 2016, driven entirely by lower land-use emissions.
In 2017, overall CO2 emissions—including land use—are likely to increase by around 1.5 percent, as land-use emissions are estimated to remain roughly the same as in 2016. This means that total CO2 emissions are likely to be similar as in 2015, with the increase in fossil fuel emissions being offset by the decrease in land-use emissions.
About 54 percent of CO2 emitted in 2016 accumulated in the atmosphere, while the remainder was taken up by carbon sinks—24 percent by the land and 22 percent by the ocean. The portion of CO2 accumulating in the atmosphere in both 2015 and 2016 was higher than average, driven in part by the large El Niño event. This is expected to drop to around 46 percent in 2017, as it is a year lacking a major El Niño.
Updating sources and sinks
The GCP's new global carbon budget also includes updated estimates of sources and sinks based on changes in inventories and new research published since the last budget came out. The figure below, taken from the paper presenting the latest budget, shows the budget values used for every year from 2006 through to present.
Global Carbon Project source and sink estimates in gigatons carbon (GtC)—note, not CO2—for every Global Carbon Budget published between 2016 and 2017. Figure 9 from Le Quéré et al (2017).
Estimates of fossil fuel emissions were revised downwards a bit from the 2016 report, particularly between 1990 and 2010. This was due largely to a change in the dataset used to estimate Chinese emissions.
The GCP's new global carbon budget also incorporates updated land-use emission estimates that significantly revise past land-use change emissions, showing higher emissions prior to 1960, lower emissions between 1960 and 1999, and higher emissions from 1999 through to present. This ends up changing estimates of cumulative carbon emissions since the pre-industrial period, but given the large uncertainties involved the authors caution against using these revisions to draw conclusions about remaining carbon budgets associated with staying within the 2°C or 1.5°C warming targets.
Implications for limiting warming to 2°C
As previously discussed by Carbon Brief, the later that global emissions peak, the more rapid the reductions must be to limit warming to 2°C. The figure below shows how the rate of reduction varies based on peak year, adding in the new estimated 2017 emissions.
Emission reduction trajectories associated with a 66 percent chance of avoiding more than 2°C warming by starting year, with new 2017 emissions added. Solid black line shows historical emissions, while dashed black line shows emissions constant at 2016 levels. Data and chart design from Robbie Andrew at CICERO and the Global Carbon Project. Chart by Carbon Brief using Highcharts.
The increase in emissions in 2017 makes it more challenging for the world to limit warming to "well below 2°C", as per the Paris agreement—at least in the absence of large-scale removal of carbon dioxide from the atmosphere from as-yet-unproven negative emission technologies later in the century.
While the slowdown in emissions over the past few years and the "peaking" of emissions by a number of countries has been cause for cautious hope, this is tempered by the uptick in emissions projected in 2017. According to UN Environment, existing commitments by nations fall well short of what is needed to meet warming targets and emissions will not fall quickly until the world undertakes much more ambitious mitigation actions.
Reposted with permission from our media associate Carbon Brief.
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Global Banks, Led by JPMorgan Chase, Invested $1.9 Trillion in Fossil Fuels Since Paris Climate Pact
By Sharon Kelly
A report published Wednesday names the banks that have played the biggest recent role in funding fossil fuel projects, finding that since 2016, immediately following the Paris agreement's adoption, 33 global banks have poured $1.9 trillion into financing climate-changing projects worldwide.
By Patti Lynn
2018 was a groundbreaking year in the public conversation about climate change. Last February, The New York Times reported that a record percentage of Americans now believe that climate change is caused by humans, and there was a 20 percentage point rise in "the number of Americans who say they worry 'a great deal' about climate change."
England faces an "existential threat" if it does not change how it manages its water, the head of the country's Environment Agency warned Tuesday.
By Jessica Corbett
A new analysis revealed Tuesday that over the past two decades heat records across the U.S. have been broken twice as often as cold ones—underscoring experts' warnings about the increasingly dangerous consequences of failing to dramatically curb planet-warming emissions.
By Madison Dapcevich
Ask any resident of San Francisco about the waterfront parrots, and they will surely tell you a story of red-faced conures squawking or dive-bombing between building peaks. Ask a team of researchers from the University of Georgia, however, and they will tell you of a mysterious string of neurological poisonings impacting the naturalized flock for decades.
The initial cause of the fire was not yet known, but it has been driven by the strong wind and jumped the North Santiam River, The Salem Statesman Journal reported. As of Tuesday night, it threatened around 35 homes and 30 buildings, and was 20 percent contained.
The unanimous verdict was announced Tuesday in San Francisco in the first federal case to be brought against Monsanto, now owned by Bayer, alleging that repeated use of the company's glyphosate-containing weedkiller caused the plaintiff's cancer. Seventy-year-old Edwin Hardeman of Santa Rosa, California said he used Roundup for almost 30 years on his properties before developing non-Hodgkin's lymphoma.
"Today's verdict reinforces what another jury found last year, and what scientists with the state of California and the World Health Organization have concluded: Glyphosate causes cancer in people," Environmental Working Group President Ken Cook said in a statement. "As similar lawsuits mount, the evidence will grow that Roundup is not safe, and that the company has tried to cover it up."
Judge Vince Chhabria has split Hardeman's trial into two phases. The first, decided Tuesday, focused exclusively on whether or not Roundup use caused the plaintiff's cancer. The second, to begin Wednesday, will assess if Bayer is liable for damages.
"We are disappointed with the jury's initial decision, but we continue to believe firmly that the science confirms glyphosate-based herbicides do not cause cancer," Bayer spokesman Dan Childs said in a statement reported by The Guardian. "We are confident the evidence in phase two will show that Monsanto's conduct has been appropriate and the company should not be liable for Mr. Hardeman's cancer."
Some legal experts said that Chhabria's decision to split the trial was beneficial to Bayer, Reuters reported. The company had complained that the jury in Johnson's case had been distracted by the lawyers' claims that Monsanto had sought to mislead scientists and the public about Roundup's safety.
However, a remark made by Chhabria during the trial and reported by The Guardian was blatantly critical of the company.
"Although the evidence that Roundup causes cancer is quite equivocal, there is strong evidence from which a jury could conclude that Monsanto does not particularly care whether its product is in fact giving people cancer, focusing instead on manipulating public opinion and undermining anyone who raises genuine and legitimate concerns about the issue," he said.
Many regulatory bodies, including the U.S. Environmental Protection Agency, have ruled that glyphosate is safe for humans, but the World Health Organization's International Agency for Research on Cancer found it was "probably carcinogenic to humans" in 2015. A university study earlier this year found that glyphosate use increased cancer risk by as much as 41 percent.
Hardeman's lawyers Jennifer Moore and Aimee Wagstaff said they would now reveal Monsanto's efforts to mislead the public about the safety of its product.
"Now we can focus on the evidence that Monsanto has not taken a responsible, objective approach to the safety of Roundup," they wrote in a statement reported by The Guardian.
Hardeman's case is considered a "bellwether" trial for the more than 760 glyphosate cases Chhabria is hearing. In total, there are around 11,200 such lawsuits pending in the U.S., according to Reuters.
University of Richmond law professor Carl Tobias told Reuters that Tuesday's decision showed that the verdict in Johnson's case was not "an aberration," and could possibly predict how future juries in the thousands of pending cases would respond.