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Population, consumption and equity

Robert Engelman demonstrates the importance of linking the issues of population and greenhouse gas reductions if global equity is to prevail.

The author directs the Population and Environment Program at Population Action International in Washington DC, USA.

The topic was barely on the table at the Fourth Conference of the Parties to the United Nations Framework Convention on Climate Change, but the issue of the fairness of current greenhouse gas emissions patterns hovered over the recently completed negotiations in Buenos Aires, Argentina.

The nature of the commitments agreed to at the Third Conference of the Parties in 1997 in the Kyoto Protocol obscured the point. It really isn’t so much nations — the size of which may be accidents of history, geography and demography — that emit greenhouse gases. It is human beings, living real lives, and possessing a framework of individual rights that has not yet evolved to capture this increasingly important one: the right to use the global atmosphere in ways that do not jeopardize the environment or other human beings.

Some human beings today send dozens of times their own body weight in carbon into the atmosphere each year, and take for granted their right to keep doing so. This, despite the impact of these emissions on other human beings who may send skyward less than their own weight. But as climate change becomes a more urgent public issue, and as governments face the need to decrease the global emissions total, more attention is likely to focus on the vast disparities in per capita emissions of carbon dioxide and other greenhouse gases.

One of the ironies of this change of focus will be an increase in interest in the impacts of different population futures on the goal of slowing human-induced climate change that does not also impoverish humanity. Indeed, the critical link between population and climate change can only be addressed from a perspective of equal access to the carbon-cycling properties of the atmosphere. Without this perspective, population’s role in climate change tends to be obscured by the yawning gap between high and low per capita emitters of greenhouse gases. There seems little scope for considering population’s role in future climate change while the industrialized countries, whose populations are growing relatively slowly and represent only a fifth of the world’s total, contribute two-thirds of all greenhouse gas emissions.

Linked to the key concepts of climate sustainability and atmospheric equity, however, population trends emerge along with technological innovation as the greatest source of hope that humanity may actually succeed in resolving the problem of climate change before catastrophic ecological change has occurred. To illustrate this key point and to demonstrate the importance of per capita emissions in understanding climate change, Population Action International released an update to its 1994 climate report, Stabilizing the Atmosphere: Population, Consumption and Greenhouse Gases, at the Fourth Conference of the Parties (see Tiempo, Issue 16, June 1995, for an excerpted account of this report).

Figure 1: A sample of per capita carbon emissions country profiles (metric tons of carbon from fossil fuel combustion and cement production). Note the change in vertical scale from country to country.

The new report, Profiles in Carbon: An Update on Population, Consumption and Carbon Dioxide Emissions, features a nearly half-century record of per capita carbon dioxide emissions from fossil fuel combustion and cement production of 179 countries (Figure 1). Figure 2 shows the geographical distribution of high, middle and low emitters in 1995.

The disparities in per capita emissions are vast indeed, demonstrating the impact unequal consumption patterns have on atmospheric change. According to Population Action International’s analysis, 20 per cent of the world’s population is responsible for 63 per cent of carbon dioxide emissions, while another 20 per cent is responsible for only 2 per cent of these emissions (Figure 3).

Figure 2: The 20 per cent of highest emitters (lightest grey), the middle emitters, and the
20 per cent of lowest emitters (darkest grey). White indicates no data.

This inequity correlates to some degree with per capita income and is similar to inequalities in wealth identified recently by the United Nations Development Programme in its Human Development Index (Tiempo, Issue 29, September 1998).

Those populations with the most financial and technical resources to adapt to climate change are disproportionately putting at risk other populations who lack these resources — and who are scarcely contributing to the problem, if at all. The situation is even less just given recent predictions that agriculture in the temperate latitudes may experience few serious impacts from climate change, while farmers in the tropical latitudes of the developing world may face significant challenges in food production. Climate change “winners” are considered likely to be the most northern populations of North America, Europe and Asia, where only a tiny fraction of the world’s 5.9 billion people live.

Consider the estimate of the Intergovernmental Panel on Climate Change that global carbon emissions would need to be cut by at least 60 per cent to stabilize carbon dioxide concentrations at roughly current levels. This suggests that, based on 1995 carbon dioxide emissions plus population data, 2.55 billion human beings living in 69 countries emitted so little carbon dioxide on a per capita basis they essentially were helping to bring the atmosphere into balance. These people were hardly compensated for their global good citizenship, and in fact they were living in poverty in close correlation to the magnitude of their contribution.

Figure 3: Relative shares of global carbon dioxide emissions by high, middle and low emitters.

These figures do not include emissions from biomass burning and land-use changes because of a lack of comparable country data. No doubt the full picture would reduce the proportion of “under-emitters” relative to “over-emitters” to some extent. Fossil fuel carbon is fundamentally different from that found in trees and soils, however, in one important respect — it was accumulated over hundreds of millions of years and buried securely underground. Once it is in the atmosphere — or in plants, soils and oceans — it will never be locked away so securely again.

In any event, the point remains the same. One of the best arguments against voluntary emission commitments by non-Annex I countries (a major topic of discussion in Buenos Aires) is that such commitments could result in long-term limits on per capita emissions that, even if generous by the country’s historical standards, would condemn its citizenry to second-class status in using the world’s fossil fuel reserves. And these are arguably the natural resources most associated, in today’s world, with prosperity. What government would agree to that?

Much more likely, eventually, is a climate agreement that drives global emissions reductions through incentives based on the equal human right to use the atmosphere. This could take the form of government-to-government tradable emission permits based on the per capita emissions of trading partners. Both the benchmark for trading and the price of trades could be set by international agreement, through a process that would reflect public perceptions of the urgency of the climate threat and the political will to address the issue. The goal would be to bring global emissions as close as possible to agreed-upon ceilings aimed at stabilizing atmosphere and climate, respecting equal human rights to use the atmosphere.

Where human population goes as climate change unfolds, however, will make a huge difference to how generous individual emissions allocations will be in the coming centuries. The good news is that, contrary to the assumptions of many analysts in the climate change field, the range of possible population paths in the 21st and 22nd centuries is wide indeed (Figure 4). Whether world population doubles or triples yet again or peaks by the middle of the next century depends in large part on policies and programmes that governments put into place today.

Figure 4: World population in 1850, the present-day and two projections for the year 2150.

All the world’s governments agreed on the principles and strategies governing these policies in 1994 at an historic international conference on population and development held in Cairo (Tiempo, Issue 13, November 1994). All action on population, the nations agreed, should be grounded in human rights and the free and informed decisions that individuals and couples make about their childbearing. In particular, population policies and programmes should consist of social investments in human development — especially improved access to family planning and related health services, to education for girls, and to economic opportunities for women. Global population policies are founded on the same basic principles of human rights and fair opportunities for development that governments are struggling to respect while addressing climate change through the UN Framework Convention on Climate Change and the Kyoto Protocol.

If governments follow through on the commitments made in Cairo in 1994, the future of world population change could resemble the United Nations’ long-term low population scenario, which extends to the year 2150 (Figure 5). Intriguingly, with regard to the overall trend, this curve somewhat resembles another projection, also shown in Figure 5, representing a global carbon dioxide emissions path that would be needed to stabilize atmospheric carbon dioxide concentrations at 450 parts per million by volume, just under a doubling from pre-industrial times. This path was proposed by Tom Wigley, Richard Richels and James Edmonds in Nature in January 1996.

Figure 5: Emissions path needed to stabilize atmospheric carbon dioxide concentrations at 450 parts per million by volume according to Wigley, Richels and Edmonds and the UN low population projection. Estimates are given at ten-year intervals.

The Intergovernmental Panel on Climate Change has proposed similar paths, but those of Wigley, Richels and Edmonds allow for even greater near-term emissions increases while imposing more stringent emissions cuts in future years. Their emissions trajectories, the authors argue, are more politically realistic because of the near-certainty of continued emissions growth over the next few years. The paths would produce long-term climate change similar to that implied by stringent reductions today followed by more modest future cuts as it is total emissions over a given time period, more than the timing of emissions changes within that period, that will determine future climate.

If one converts the historic and proposed global carbon dioxide emissions path to comparable per capita emissions paths based on the full range of United Nations’ population scenarios, the result is instructive. If population follows the high path, growing to 27 billion people by 2150, the resulting global per capita emission capable of stabilizing atmospheric carbon in that year would need to be held to the level of per capita carbon emissions from the middle of the 19th century. Under the low population projection, by contrast, with world population peaking around 7.7 billion and then gradually declining to 3.6 billion in 2150, the climate-sustainable per capita emission amounts to what it was just prior to World War II. The figure would actually be growing in the first half of the 22nd century, as world population gradually declined in the context of a relatively stable global ceiling on emissions.

Obviously, a transformation of energy use from waste to efficiency and from carbon to non-carbon sources will need to occur between today and 2150, regardless of feasible demographic change. Just as clearly, the challenge this transition poses will be eased by a lower rather than higher population trajectory, and that difference could prove critical to the global environment.

In recent decades the Law of the Sea established a key principle, which is that all human beings share an equal right to use the common property of humankind. Surely the atmosphere is such a global commons? Ultimately, the world’s governments will need to recognize that long-term efforts to slow climate change will depend on a fair allocation of that right based on per capita, more than national, emissions of greenhouse gases.

Once governments come to this realization, they are likely to reassess the priority of another historic agreement, the Programme of Action agreed to at the International Conference on Population and Development in Cairo in 1994. That agreement provides a road map to a stable or even gradually declining population in the next century, based on the healthy childbearing decisions of free and informed couples and individuals. It also points the way to a world in which all human beings have access to the global atmosphere for modest emissions of greenhouse gases that could continue indefinitely into the future without adding to the risk of human-induced climate change.

Profiles in Carbon advances three recommendations for immediate action:

  • the Intergovernmental Panel on Climate Change should specifically explore the interaction of population dynamics with other factors related to climate change in the Third Assessment Report;
  • the Programme of Action developed by the 1994 International Conference on Population and Development should be referenced specifically in future protocols to the Framework Convention on Climate Change, signalling a recognition that these two issues, climate and population, are inseparable, and,
  • a clearer focus on differences in per capita emissions of key greenhouse gases, especially carbon dioxide, is needed in the scientific and policy debate on the climate issue.

The report Profiles in Carbon: An Update on Population, Consumption and Carbon Dioxide Emissions is available at no cost to readers of Tiempo. To obtain a copy contact Akia Talbot at Population Action International at the address below. The full text of the report, including tabulated data for 1995, is also available at Population Action International’s web site.

Further information

Robert Engelman, Population Action International, 1120 19th Street NW, Suite 550, Washington DC 20036, USA. Fax: 1-202-2931795. Email: Web:

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