The Ecological "Arc" of the World Economy

The following entry contains nothing new about carbon emissions that hasn't already been picked up by the media; instead, it seeks to present the facts differently. 

The map below shows the total size of CO-2 emissions over five decades where each bubble represents total emissions by a country. If you hit the play button, you will see the gradual growth of emissions over time. Quite striking is the rise of China over the past decade dislodging the US as the biggest emitter with 6 million kilo tons (kt) of emissions compared to 5.7M for the US. Russia and India follow suit with about 1.5M kt each, and Japan ranks fifth with 1.3M kt.

The next chart plots the CO-2 emissions per capita of each country along the vertical axis with  average incomes (gross national income per capita) on the horizontal axis based on purchasing power parity (or PPP) measuring income in terms of what citizens can afford based on the cost of goods and services relative to wages. The bubbles represent the population size of each country.

One sees clearly an "arc" that gradually slopes upwards such that as countries get richer, each citizen consumes more resources and generates more pollution. From 1980, this arc gradually moves rightwards reflecting technological advances that have made industries more efficient in their use of resources, i.e. it takes less carbon to produce a dollar's worth of goods. In 1980, the point at which emissions per capita started to rise was at $1,000. In 2006, it was close to $4,000.

For the world economy to grow in a sustainable way, rapid technology development is needed to make production less reliant on carbon so that as poorer countries move up the income scale, they do not cause environmental damage at a rate similar to that of rich countries in the past. The arc needs to be flattened and pushed rightwards. It is not viable to prevent the rise of affluence in poorer nations as poverty tends to be correlated with faster population growth.

China with its 1.3 billion people earning $4,700 on average is already on the upward sloping part of the arc. Displacement of industries from rich countries that have stringent environmental policies is largely responsible. Egypt which has about the same level of income per person as China, emits 3-kt per capita compared to China's 5-kt reflecting a different mix of industries. India with an average income of $2,500 per person still lies on the flat portion of the arc and has a relatively low carbon footprint of 1-kt.

For the arc to flatten and shift rightwards, incentives are needed to encourage investments in new technology that will shift production away from carbon intensive methods and into cleaner ones. The rate of technological progress has to be faster than economic progress of poorer nations. The arc has to be bent downwards faster to accommodate the bigger but poorer nations who are "catching up" with the smaller but richer ones. If not, the future well-being of all those who live on the arc could be at-risk. 

For a discussion on the history of the science behind global warming, I found the following source quite illuminating: http://www.aip.org/history/climate/ from the American Institute of Physics.