What is the connection between carbon emissions, life expectancy and income?

Until recently, the following correlations have been held to be true: Human development depends on economic growth, economic growth requires additional energy and thus leads to increased emissions of greenhouse gases. Consequently, humanity cannot evolve without further exploiting Earth's resources. However, these correlations are neither as strong, nor as universally valid as originally thought. These mutual dependencies are the subject of numerous investigations.

Julia K. Steinberger (University of Leeds & Alpen-Adria-Universität), J. Timmons Roberts, Glen P. Peters, and Giovanni Baiocchi have jointly published a study in Nature Climate Change, in which they explore the links between carbon emissions and human development.

During their investigations, life expectancy, income, and carbon emissions were viewed in terms of how they relate to each other. In addition, emissions were categorized as either territorial (e.g. due to industrial production in the respective country), or consumption-based emissions (net values are derived by adding imported emission values and subtracting exported emission values based on the carbon embedded in goods and services). Overall, it is possible to show -- in accordance with the latter approach -- that most carbon-exporting countries, such as those from the former Soviet Union, Eastern Europe, the Middle East, or South Africa can be found in the middle range, both in terms of life expectancy and in terms of income. Carbon-importing countries, however, represent an exceptionally heterogeneous group, consisting of two extremes: On the one hand, these are the poorest countries, forced to import expensive fossil fuels as well as goods produced at high carbon intensity. On the other hand, this group includes those countries with the most developed socio-economic status, the highest life expectancy and a greater average per capita income.

The research revealed that although both territorial and consumption-based carbon emissions are highly correlated with human development, the shape and strength of the relationship between carbon emissions and income is entirely unlike the relationship between carbon emission and life expectancy.

The country comparison shows that while it is possible to simultaneously achieve low carbon emissions and high life expectancy, this only applies when the population's income is moderate. Economic and environmental objectives seem to contradict each other; this certainly appears to be the case for the highest per capita GDP values. Furthermore, researchers were able to demonstrate that a wide variety of development opportunities exist in these countries, which do not necessarily follow global trends. Commenting on the prospects for the future, Julia K. Steinberger explains: "Since countries currently exist with the same life expectancies as the UK and the US, but with a small fraction of their carbon emissions (and incomes), prioritising economic growth at the expense of climate stability seems less and less defensible."