A recent article in the New York Times by Eduardo Porter (here) points out that if one considers only carbon dioxide emissions (CO2) from the combustion of fuels, then worldwide emissions have been flat for 3 years in a row.
The finding comes from a news release issued by the International Energy Agency (IEA). Figure 1 shows the data. Between 1980 and 2014, global CO2 emissions from fuel combustion grew from 17.7 billion metric tons to 32.3 billion metric tons. However, in 2015 they stayed at 32.3 billion metric tons, and in 2016 emissions were 32.1 billion metric tons. (IEA 2017a, 2017b)
Since 2005, CO2 emissions from fuel combustion have declined in the OECD from 12.8 billion metric tons to 11.7 billion metric tons, a decline of 8.6%. In the United States, emissions declined from 6.71 billion metric tons to 5.00 metric tons (a decline of 25%). That’s good work, however it needs to be put in context. Compared to 1990, OECD emissions in 2016 were 6.4% higher, and USA emissions were 4.1% higher. (IEA 2017a)
I don’t have breakouts by country for 2016, but in 2015 the world’s largest emitter of CO2 from fuel combustion was the People’s Republic of China (mainland China), at 7.28 billion metric tons. Even China is reducing its emissions, however, by 1% in both 2015 and 2016. (IEA 2017a)
Emissions from fuel combustion may be the best estimate of worldwide emissions available. They constitute the largest percentage of emissions, and it is virtually impossible to inventory how much methane is being released by every bog or permafrost around the world, or how much nitrogen oxide from farm chemicals, etc.
In August I posted that the American Meteorological Society reported that in 2015 the concentration of CO2 in the atmosphere averaged above 400 ppm for the first time ever. It was my opinion that this was terrible news: 400 ppm was something akin to a threshold we needed not to cross in order to avoid the worst effects of climate change. We crossed it decades before anybody thought we would. Further, the concentration of greenhouse gases was continuing to increase, and the rate of increase seemed, if anything, to be growing over time. Figure 2 repeats the chart showing the trend over time.
How can one reconcile that post with the new findings? Imagine you are on the Titanic, and an hour ago the ship struck an iceberg. The ship’s crew happily reports that the amount of water getting into the ship is no longer increasing minute-by-minute. Well, that’s nice to hear, but water is still pouring into the ship, and unless you can stop the water getting in, the ship will still sink. The CO2 situation is similar, but in reverse. The rate at which the world is putting CO2 into the atmosphere may not be going up, but we are still putting billions of tons of it into the atmosphere every year. It is more than enough to cause climate change. We don’t need emissions to flatten, we need them to decrease to a fraction of what they are today.
So, it is good news that worldwide emissions have not grown over the last 3 years. Perhaps it even tends to validate the efforts we’ve been making: maybe moving away from fossil fuels, especially coal, has helped stabilize emissions. But we have a long way to go before we stop this vessel of ours from sinking.
UPDATE: The Global Carbon Project released a report published 11/13/2017 (after this post was written) that projects 2017 carbon emissions from combustion of fuels will increase 2% from 2016. If their estimates prove correct, then the period of flat emissions will be over, and emissions will have resumed their upward climb. (Global Carbon Project, 2017)
Earth System Research Laboratory. 2017. Full Mauna Loa CO2 Record. Downloaded 2017-06-15 from https://www.esrl.noaa.gov/gmd/ccgg/trends.
Global Carbon Project. 2017. Global Carbon Budget: Summary Highlights. Viewed online 11/15/2017 at http://www.globalcarbonproject.org/carbonbudget/17/highlights.htm.
International Energy Agency. 2017a. CO2 Emissions from Fuel Combustion: Highlights. Downloaded 11/09/2017 from https://www.iea.org/publications/freepublications/publication/CO2EmissionsfromFuelCombustionHighlights2017.pdf
International Energy Agency. 2017b. IEA Finds CO2 Emissions Flat for Third Straight Year Even as Global Economy Grew in 2016. Downloaded 2017-11-09 from https://www.iea.org/newsroom/news/2017/march/iea-finds-co2-emissions-flat-for-third-straight-year-even-as-global-economy-grew.html.