Carbon dioxide emissions are an area of significant concern in the international system. Many scientists have suggested that such emissions are causing global warming, the increase of the worldÕs net temperature. The Kyoto talks have sought to create a treaty that would reduce carbon dioxide emissions in industrialized countries. Many of these talks have been critical of the United States for their large per capita carbon dioxide emissions. Many players in the international system were particularly upset when the United States refused to ratify the Kyoto treaty. This has left the impression in many nations that the United States does not care about world environmental problems.

Is the United States truly at fault for having such high per capita carbon dioxide emissions? There must be reasons for the United States consuming more energy then the rest of the industrialized world, and releasing much more carbon dioxide gas. Several reasons in the past have been suggested, including the lack of energy efficiency in America, our love for big sport utility vehicles, and our status as a wealthy industrial leader. Yet, it seems that all of those suggestions are flawed in at least some way. The United States has made great strides since the 1970s in energy conservation. Many sport utility vehicles are relatively efficient, and their popularity is often overstated in popular media. A postindustrial state should be releasing fewer emissions due to its smaller amount of heavy industry and better social regulation. There is probably a better reason states like the United States release significantly more carbon dioxide per capita then states like Germany and France.

Hypothesis:
Larger States Produce More Carbon Dioxide

One must consider an important difference between the United States and the many smaller European states. The United States has the worldÕs second largest landmass of high-income states. Only Canada has a larger landmass. It seems that the size of big states demands greater fuel consumption and subsequent carbon dioxide emissions for several reasons. Large states typically have to transport various products manufactured at great distances away. Typically, such states have many places where transport by barge and other efficient ways are impractical. Instead, they must rely on less efficient tractor-trailers to transport goods around the country. Similarly, there are big differences in the distance that goods need to be moved. German cars need not be moved as far to be sold in France as American cars to be sold in California. Also, there is a big difference in the transportation systems in big states and small states. With a larger landmass, it takes significantly more energy to move people around the country in large country. Mass-transit is impractical in large states such as the United States, due to the spread out nature of the population. Cost and time make it prohibitive to have subways and buses run outside cities and major suburban hubs. Suburbs dominate land-rich nations; there is space for more than the population to live in suburbs in the United States. Similarly, land rich nations have significant rural populations with many long-distance commuters. Around 20% of American citizens live in rural areas and an even larger percentage of Canadians live in such areas (US Census). Larger states have room for superhighways and streets big enough to hold larger vehicles. Driving a Chevy Silverado around narrow European streets is impractical, even if a person is a mechanic who needs the room to carry tools and the ability to tow large trailers. Few Europeans need off-road capabilities in their vehicles. This is probably why large vehicles with higher fuel consumption are more common in larger nations. It is likely that large nations will have significantly larger carbon dioxide emissions then smaller nations.

Methodology

To test the hypothesis that states with larger land mass will produce larger carbon dioxide emissions per capita; this paper will examine the relationship of carbon dioxide emissions and land area. Thirty-nine high-income countries will be considered, as defined by the World Bank (Databank, 2003). It is reasonable only to consider high-income countries, as they are similar in wealth, their stages of industrialization, and all have some form of state-capitalism. As such, state regulation will be similar, as will citizensÔ abilities to select and purchase material goods such as large cars. Certain countries would not make sense to include in this comparison due to their distinct characteristics that make them different from other high per-capita countries in carbon dioxide emission levels. Table B labels these abnormal states as Ôexcluded statesÕ. The excluded states are not included in any calculations or graphs used in this paper. The five major-oil-producing nations that have an effective high per capita income is not equal to small and non oil producers. Their oil production leads to significant carbon dioxide emissions per capita. All five of these states produced over 20 tons per capita of carbon dioxide, significantly more then the rest of the high-income nations of the world. They were therefore excluded from calculations. Singapore was excluded due to itÕs extreme differential in per capita wealth, and its status of a country industrializing. SingaporeÕs significant industrialization has caused it to have per capita carbon dioxide emissions different from other states of similar size. Luxembourg had high per capita carbon dioxide emissions that could not be explained and therefore were excluded. The US Virgin Islands were excluded due to their suspect numbers. Average emissions for the Virgin Islands is well over 100 tons per capita. There is no clear reason on why such numbers should be so high. Including such numbers would distort the graph and correlation, and would make the data less useful.

Results

The evidence in the table, graph, and linear regression appears to support the hypothesis that larger states are more likely to produce greater carbon dioxide emissions per capita then smaller states. The largest wealthy states such as Australia, Canada and the United States produced significantly larger emissions then moderately sized European states. Many of smallest high-income states such as Cyprus, the Bahamas, and Slovenia produced smaller per-capita emissions then medium-sized states such as the Netherlands, United Kingdom, and Italy.

Limitations

Yet, the results of this study are limited in their usefulness. The linear regression showed that correlation between per capita carbon dioxide emissions and land area is not particularly strong. After calculating the correlation, there was a r2 value of 0.635425. This is not an indication of a strong correlation, but it shows that there is a relationship between land area and carbon dioxide emissions. The graph shows that there is no significant correlation between state size and carbon dioxide emissions for states of a similar size to one and another, as for many European states. Instead, other factors may be causing a discrepancy between expected per-capita carbon dioxide emissions and real carbon dioxide emissions. For example, the United Kingdom was predicted to release 8.00 metric tons of carbon dioxide per capita, but they actually produced an average of 9.225 metric tons per capita in 1998 and 1999. However, this is not surprising, as the United Kingdom is a particularly wealthy country, with extensive industry that produces a significant amount of carbon dioxide.

One major flaw in this study, was a lack of comparable states. Every country in the world has a different gross domestic product, is in a different stage of industrialization, and has a different population with disparate cultural preferences. This paper attempts to counteract such tendencies by only considering high-income states as classified by the World Bank Databank (2003). In particular this posed a problem for comparing large countries, as there are only three large high-income countries. The additions of Russia and China to this list were considered, but their lower per capita wealth appeared to influence their carbon dioxide emissions data in ways that are not productive to this study. Australia, the United States, and Canada are big carbon dioxide producers and have large landmasses, but there may exist factors that are specific just to these three countries. For example, inefficient automatic transmissions are common in North America, while Europeans prefer manual transmissions. There is no obvious relation between this fact and land size, as when driving on high-speed roads shifting is rarely necessary. Most of the full-size pickup trucks and sport utility vehicles are manufactured and sold in North America. A logical conclusion of the preference of North American manufactures producers creating such vehicles would be larger vehicle sales of large vehicles. Neither of these facts is considered in the study of the hypothesis.

A future study of per-capita carbon dioxide emissions versus land area should also consider gross domestic product, population, and cultural preferences. Adding these variables would not only correct for biases, but might also lead to additional answers on the causes the increase in carbon dioxide as country size grows. The study is too simplistic to prove the exact reason for the increase in carbon dioxide emissions as country size increases.

Conclusions:
Evidence Supports the Hypothesis, But More Study is Needed

The United States receives more blame then it likely deserves for its contribution to global warming. It appears that high-income states with large landmasses contribute more carbon dioxide to the atmosphere then smaller wealthy states. The correlation between the two variables is weak, but there is a definite increase of carbon dioxide emissions in the US, Canada, and Australia compared to the smaller wealthy European states. It should be noted that this paper does not show any thing beyond the weak correlation of country size and carbon dioxide, so making assumptions on the causes of global warming may be misleading.

Table A: Included States

Note: Several high-income countries were not considered in this paper due to abnormally high per capita carbon dioxide emissions. They are listed on Table B.

Source: World Bank. (2003). WorldBank Databank. Retrieved November 7, 2003 from the World Wide Web: http://devdata.worldbank.org/data-query/Datasets Used: High Income Countries: 1999 Land Area (in Square Kilometers), 1998/1999 (averaged) Carbon Dioxide Emissions Per Capita (in Metric Tons)

Table B: Excluded States

Note: The excluded states are not included in any calculations or graphs used in this paper. The five major-oil-producing nations that have an effective high per capita income is not equal to small and non oil producers. Their oil production leads to significant carbon dioxide emissions per capita. All five of these states produced over 20 tons per capita of carbon dioxide, significantly more then the rest of the high-income nations of the world. They were therefore excluded from calculations. Singapore was excluded due to itÕs extreme differential in per capita wealth, and its status of a country industrializing. SingaporeÕs significant industrialization has caused it to have per capita carbon dioxide emissions different from other states of similar size. Luxembourg had high per capita carbon dioxide emissions that could not be explained and therefore were excluded. The US Virgin Islands were excluded due to their suspect numbers. Average emissions for the Virgin Islands is well over 100 tons per capita.

Source: World Bank. (2003). WorldBank Databank. Retrieved November 7, 2003 from the World Wide Web: http://devdata.worldbank.org/data-query/

Datasets Used: High Income Countries: 1999 Land Area (in Square Kilometers), 1998/1999 (averaged) Carbon Dioxide Emissions Per Capita (in Metric Tons).

Table C: Included States by Fifth

Source: Table A averages for each fifth.

Table D: All States by Fifth

Source: Table A and B averages for each fifth.

References

World Bank. (2003). WorldBank Databank. Retrieved November 7, 2003 from the World Wide Web: http://devdata.worldbank.org/data-query/

US Census Bureau (2002). Metropolitan Area and Central City Population Estimates for July 1, 1999 and Revised April 1, 1990 Census Population Counts. Retrieved April 5, 2002 from the World Wide Web: http://www.census.gov/population/www/estimates/metropop.html