By Kristiina Joon
Disappointingly, 2019 saw global carbon emissions continue to rise, as outlined in the UN Emissions Gap Report.
Atmospheric carbon dioxide levels reached a recorded-breaking level of 415 ppm as measured by the Mauna Loa Observatory; this is roughly 1.5 times higher than the concentration at the beginning of the last century.
The good news is that whilst 2019 saw emissions rise, the rate of increase is slowing down. “Emissions from coal, oil and natural gas expanded by about 2% globally in 2018. In 2019 it is predicted emissions rose by 0.6% and this is about a third of the growth rates we’ve seen of the previous years, so it is actually a quite significant slowdown.” says the Executive Director of the Global Carbon Project.
The bad news is there is no sign of these emissions peaking in the next few years. Given that the level of warming depends on the total, cumulative emissions, the longer we allow them to rise, the more drastic will the cuts to emissions need to be to stay within 1.5°C or 2.0°C warming scenarios.
What does our procrastination mean in practice?
In order to keep warming under 2 degrees carbon dioxide emissions must fall by 25% over the next decade. Yet 1.5 degrees is the only chance of survival for many regions and we would need to cut emissions by a staggering 55% to achieve this.
The earlier we act, the easier this will be. 10 years ago, if countries had acted on the science, governments would have needed to reduce emissions by 3.3% each year. Now that figure has more than doubled to a reduction of 7.6% every year.
Sources of CO2
Despite commitments to reduce fossil fuel use, almost all human activities that produce greenhouse gases saw a rise in emissions in 2019 compared to 2018. This includes the burning of fossil fuels for generating electricity, transportation, cement production needed for construction, and land-use change. The burning of coal continues to be the largest contributor of global emissions, followed by oil. Together these two sources contribute to about 70% of the total emissions. Gas emissions add up to about 20% of the total emissions, and the production of cement gives 5-10%.
However, whilst coal is a large contributor, it is on the decline whereas the burning of natural gas is predicted to have risen by 2.6%. Unfortunately an increased use of gas is not replacing coal but being used as an additional source of energy in many regions.
Emissions from land-use change are difficult to quantify and estimates have large uncertainties, so it is difficult to report an exact number.
Who are the major emitters?
Country rankings change considerably when comparing absolute and per capita emissions: per capita emissions are by far the highest in the US and have now in China reached a similar level to the EU. The largest emitters have the opportunity to make the biggest changes globally.
The graph above shows territorial emissions. Such a measure of emissions can unfairly square the blame on countries like China because it doesn’t take into account consumed emissions, which can be significantly larger in regions like the EU and the US. As major importers of energy and goods, they have a very high level of consumed emissions in addition to territorial emissions. EU per capita emissions are higher than Chinese when consumption-based emissions are included. The graph therefore covers a multitude of sins - namely those of regions with much higher carbon footprints than at first appears.
This is not to say China is absolved of its responsibility to reduce its emissions (if China’s increase in CO2 emissions were removed from the global total, the rest of the world managed to lower emissions by -0.02GtCO2.) Rather, we must accept our collective responsibility and take the disastrous rise in emissions alongside the extreme weather events of this past year as a wake-up call to take on more fundamental changes.
United Nations Environment Programme (2019). Emissions Gap Report 2019
Friedlingstein et al. 2019 ‘Global Carbon Budget 2019’, Earth Syst. Sci. Data, 11, 1783–1838, 2019
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