Â鶹´«Ã½AV

This article is the second of a two-part series on views about global warming. focused on awareness of the issue and its causes. The second examines the relationship between these views and objective indicators of a nation's energy efficiency.

WASHINGTON, D.C. -- Â鶹´«Ã½AV data collected in 127 countries in 2007 and 2008 reveal a relationship between the percentage of citizens who believe global warming is a result of human activities and the amount of GDP produced for every unit of energy consumed.

According to data collected by the World Bank and summarized by the United Nations Development Programme, countries differ widely in how much energy they burn to produce the same amount of GDP. The previous graph focuses on 79 countries in Â鶹´«Ã½AV's data set where a majority (more than 50%) of the population report having at least some knowledge of global warming and for which the World Bank's energy efficiency measures are also available. After all, it is mainly in countries where most people have heard of global warming that one would expect perceptions of the causes of global warming to be related to a nation's energy efficiency.

The graph reveals that in countries where more people believe that global warming is the result of human activities, the amount of GDP that is produced per unit energy consumed is higher. In the United States, for example, 49% of the public believes that global warming is the result of human activities, a value that is below the international median of 54%. In keeping with this, the average amount of GDP that is produced for every kilogram of oil burned in the United States ($4.60) is on par with the international median of $4.80 (U.S. dollars in 2000). That is, when U.S. residents burn the equivalent of about a quart of oil, they typically produce $4.60 in goods and services.

To appreciate this association, consider some examples of countries that fall well below and well above the world median in their beliefs that global warming is the result of human activities. In Zimbabwe, Iceland, and Uzbekistan, less than half of respondents say they believe global warming is the result of human activities. All three of these countries also produce less than $3.00 in earnings (U.S. dollars in 2000) for every kilogram of oil burned. In contrast, Costa Rica, Hong Kong, and Colombia all rank near the top of the international list, with at least 75% of respondents saying they believe global warming is the result of human activities. In all three of these countries, residents produce at least $10.00 in earnings for every kilogram of oil burned.

Readers may wonder if this association between public opinion and energy efficiency simply reflects the wealth or level of development of different nations. Wealthier nations do produce their GDP somewhat more efficiently. Further, the citizens of wealthier nations are more likely to report that global warming is the result of human activities. However, the association described here still holds up after controlling statistically for a nation's GDP. It also holds up after controlling for a nation's literacy rate (an alternate indicator of development).

Discussion

Whereas the connection between views about global warming and efficiency of GDP production has implications for public policy, the question of causality remains. Any number of factors could be affecting the relationship, ranging from news and policies about global warming to technologies available in each country. A recent survey of earth scientists found that 97% of climatologists surveyed believe that humans play a role global warming. However, policy-makers should be aware that public opinion on the causes of global warming varies widely. Further, such public perceptions may play a role in economic and environmental outcomes.

Click page 2 to see rankings of all 79 countries on perceptions of global warming and GDP per unit energy consumed.