CO2 ISSUES

Different Ways of Looking at the Carbon Dioxide issue: What do the Nations of the World Have To Do?

Aerosol and Air Quality Research Laboratory (http://aerosols.wustl.edu/aaqrl)

Department of Energy, Environmental and Chemical Engineering
Washington University in St. Louis

Tel: 314-935-5548

[PLEASE ACKNOWLEDGE AUTHORS IF YOU USE ANY OF THE INFORMATION IN THIS REPORT]

The nations of the world are meeting in Copenhagen, Denmark in December 2009 to discuss, decide and hopefully agree upon strategies to combat the continued increase of atmospheric carbon dioxide concentrations. While representatives from different nations will be attending the UN Summit in Copenhagen, it should be clear that they represent their only home “planet Earth”, and hence should work together to come up with implementable actions.

The problem is rather complex, and this paper outlines different ways of examining the carbon dioxide issue. A series of data are plotted to facilitate this understanding. Finally, some broad recommendations are proposed. This report does not delve into the impacts of carbon dioxide on climate change; but relies on available data (www.eia.doe.gov) to examine carbon dioxide emissions. Clearly, the increasing levels are impacting the climate, and hence the need for action. The follow up action would be in the reduction of emissions of carbon dioxide, the subject of this report.

There is a carbon dioxide cycling on the planet, with both natural and anthropogenic sources and sinks. The magnitude of the natural sources and sinks are large, and the net balance has resulted in a certain concentration of carbon dioxide in the atmosphere. However, it is now well understood that anthropogenic or man-made emissions of carbon dioxide have resulted in a significant increase of atmospheric concentrations of carbon dioxide over the last 50 years.

Figure 1 Atmospheric carbon dioxide concentrations as a function of total global anthropogenic emissions starting from 1950 to 2006.

As the contributions from the natural sources and sinks have been similar over this time period, the changes in atmospheric levels (Figure 1) can be attributed to anthropogenic sources. In the scientific community, there is now an understanding that the increased carbon dioxide levels are altering the global climate patterns. Though the climate models are very complex and associated with uncertainties, there is a well accepted understanding that anthropogenic emissions of carbon dioxide have to be curtailed to arrest the continued rise in atmospheric levels, which may result in unknown, catastrophic climate changes.

There are number of ways in which the carbon dioxide issue can be examined for various nations. Data for different nations have to be examined, as eventual regulation and control of emissions will be implemented at a national scale. These can be summarized as follows:

a) the cumulative emissions of carbon dioxide over the last hundred years,

b) temporal changes of emissions of carbon dioxide

c) the total emission of carbon dioxide for the different countries

d) the per capita carbon dioxide emissions

e) the carbon dioxide intensity (carbon dioxide emissions per GDP)

Figure 2 Cumulative contributions of the major CO2 emitting nations over the last 100 years. The contributions in 20 year increments is also illustrated.

Many of the developing nations are looking at the United States as a prime contributor over the past many years. One argument is that the United States has used inexpensive fossil fuels to develop its economy, and should bear the greater responsibility. While this is true, by no means, can we afford the developing nations to emit a cumulative amount equal to that of the United States, before they begin to impose cuts.

Another interesting feature in Figure 2 is the rate of increase of carbon dioxide emissions. While the amounts emitted by the US have remained approximately constant in the last 20 years (1986 to 2006) in comparison to the previous 20 year period (1966 to 1985); the same is not true for China where the rate has been increasing significantly. The same is true for India, where the rate has been increasing, albeit not as much as China. This is very clearly illustrated in Figure 3, where the carbon dioxide emissions for China, USA and India are plotted as a function of the year.

Figure 3 Annual emissions of carbon dioxide for USA, China and India from 1980 to 2006. China has the highest rate of increase in recent years, and is now the largest emitter of carbon dioxide.

Most nations of the world are highly reliant on fossil fuels. Hence, the carbon dioxide emissions per year are correlated to the primary energy consumption as plotted in Figure 4. The relative distribution of the carbon dioxide emissions per energy consumed however varies. Clearly, nations such as France have a lower ratio as their portfolio has nuclear energy (carbon free source) in the mix. Certain smaller countries such as Norway have a large fraction of hydroelectric sources in their mix. However, by and large, fossil fuels dominate, and Figure 4 illustrates the trend clearly.

Figure 4 Annual carbon dioxide emissions plotted as a function of primary energy consumed by the various nations. China and USA are the lead consumers of energy and production of carbon dioxide, followed by Russia, Japan and India.

Figure 5 is a plot of per capita carbon dioxide emissions per year as a function of per capita energy consumption. The relative position of the various countries change due to population differences and various stages of developed status. The relative positions also change due to inefficiencies in energy usage and different portfolios of fossil fuels that are used. For example, China uses less primary energy than the United States, however, emits more carbon dioxide (Figure 4). This is due to more of coal in their primary energy mix. The dotted lines indicate the ratio of carbon dioxide emitted per kwH energy content of the primary energy source. Clearly, coal emits the highest amount of carbon dioxide of all the fossil fuels. Figure 5 pushes India and China to the bottom of the curve due to their large populations that are still to climb the development ladder. If the entire population were highly productive, then the energy consumed would be very high; and if the mix was based on fossil fuels, then the carbon dioxide emissions would be very high.

Figure 5 Per capita carbon dioxide emissions as a function of per capita energy consumption. While the graph has a linear correlation, the relative order of the nations is changed. India and China with large populations move to the lower end of the curve. An alarming fact is that if these nations were fully developed, the carbon dioxide emissions as a whole would be extremely large. [Adapted from Thimsen, PhD Thesis, WUStL, 2009]

The next graph, Figure 6, plots the carbon dioxide intensity (carbon dioxide emissions normalized by the GDP). Clearly, the United States of America has been a relatively more efficient user of energy with respective to production of GDP – and hence has a low carbon dioxide intensity even though its energy portfolio is dominated by fossil fuels. France and Norway have even lower carbon dioxide intensities as their energy portfolios have a sizeable fraction of non – carbon emitting sources (nuclear and hydroelectric). India, China and Russia are poor with respect to this indicator. Hence, these nations are proposing that they will reduce their carbon dioxide intensities over the next decades.

Figure 6 Carbon dioxide intensity (carbon dioxide emissions per unit GDP) for various countries. The intensity could be low due to efficient use of energy, or due to non-carbon based sources in the energy mix.

The energy portfolios of some of the nations who are the highest carbon dioxide emitters is shown in Figure 7. Clearly, fossil fuels dominate the energy portfolios, and hence it is important for these nations to develop strategies to reduce carbon dioxide emissions.

Figure 7 Energy portfolios of nations that are high carbon dioxide emitters. As expected, fossil fuels dominate the portfolios. India and China that are on a fast development path are more reliant on coal.

What should the nations of the world do to tackle the carbon dioxide issue? First, one nation or a group of nations should not be pointing at another group to take action, before they indicate that they would take action. While there maybe a historical basis of inequities in CO2 emissions, it is imperative that all nations take collective action. Here are some suggestions:

1) All nations of the world should return from Copenhagen with a promise to curtail carbon dioxide emissions. Clearly, the cuts should be graded – but all nations have to cut emissions. Different nations will have to come up with different methodologies and approaches – but all have to implement programs that result in reduction of carbon dioxide emissions. It is clear that the developed nations should transfer technologies that will help developing nations in the reduction of carbon dioxide emissions. The first and foremost is the demonstration and deployment of technologies for the capture of carbon dioxide from fossil fuel systems.

2) Developed nations should agree to accept higher reduction standards (based on past cumulative contributions). Developing nations should also impose cuts – based on the best available technology.

3) The pricing structure and impacts of the cuts should be evaluated. Emission cuts should not result in shift of manufacturing to higher polluting regions (with a clear price tag for goods produced in high carbon dioxide emitting nations). Eventually the public at large have to pay more for energy use (as carbon dioxide mitigation technologies will be adopted).

4) Whatever agreements are adopted should result in a reduction of total global carbon dioxide emissions (with graded contributions from all nations). Carbon trading and other “passing the buck” type approaches may not be the most effective. A technology based approach should be adopted to curtail emissions of carbon dioxide.

5) Technology for curtailing carbon dioxide emissions should be demonstrated starting “now”, without waiting for further action. Energy efficiency programs, alternate energy source development and other approaches that help us operate in a carbon constrained world should be researched, developed and deployed so that transformational changes can result.

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