Linking Population, Poverty and Development

Key Messages and Related Research on Population Dynamics And Climate Change

Population Dynamics

UNFPA documents

External papers


Consumption drives climate change, and different groups of people consume differently. However, many analyses of the impacts of population on climate change fail to take these differences into account. Age structure, household size and spatial distribution all affect per capita emissions, and should be integrated into climate change modeling.

Age Structure

Older people who are past their peak working years consume less and produce fewer greenhouse gas emissions than working-age people. Worldwide, the proportion of older persons is rising, with UNDP projecting an increase in the proportion of people over 60 years of age from 10 per cent in 2005 to 22 per cent in 2050. All things being equal, this will result in a reduction in emissions over time.

Household Size

Household sizes are declining in many places around the world, linked to processes like urbanization. Many argue that the household, and not the individual, is the best base unit for measuring emissions, as households generally consume together and often produce together. If household sizes are shrinking, the total number of households will increase even if the total population remains stable. Due to economies of scale, larger households, while emitting more in total, emit less per capita. Decreases in household size therefore mean more emissions, even without more people.

Spatial Distribution

The urban-rural distribution of the population is a major determinant of emissions levels, though not always in predictable ways, as described below.


The battle for a sustainable environmental future is being waged primarily in the world's cities, where population, economic activity and environmental issues are increasingly concentrated. As cities in the developing world grow, unmanaged urbanization can outpace infrastructure and environmental safeguards, leading to high pollution and carbon dioxide emissions and to increasing vulnerability for residents.

Yet, greater density in urban areas also allows urban residents in some cities to have lower per capita emissions relative to those living outside of the cities. Better urban planning, so essential to poverty reduction, women's empowerment and slum improvements, could help mitigate greenhouse gas emissions, while also providing resilient and adaptive environments to reduce vulnerability, particularly for impoverished urban dwellers.


UNFPA documents

  • Gender and Climate Change Key Messages
  • UNFPA's State of the World Population 2009 - Coming November 2009
  • Gender and Climate Change Toolkit (due out in 2009)


In every society, women and men have distinct responsibilities, knowledge and needs which are essential to addressing the effects of climate change. Women's historic disadvantages — their restricted access to resources and information and their limited power in decision-making — make them most vulnerable to the impacts of climate change. Rural women in developing countries are still largely responsible for securing food, water, and energy for cooking and heating. Drought, deforestation and erratic rainfall cause women to work harder to secure these resources. Women, therefore, have less time to earn income, get an education, or provide care to families. Girls regularly drop out of school to help their mothers gather fuel wood and water.

Women can be also critical agents in mitigating and adapting to climate change. Their responsibilities in households and communities position them well to develop strategies for adapting to changing environmental realities. They can play an essential role in the climate change negotiation process as well as in the development of sustainable and ecologically sound consumption and production patterns and approaches to natural resource management.

Vulnerability and Adaptation

The impacts of climate change are already apparent, from droughts and floods to weather patterns and destabilized livelihoods, and they are being felt disproportionately by those who are already impoverished. Adaptation means managing the unavoidable consequences of climate change. Analyzing population dynamics can clarify who is most vulnerable, why, and how interventions can most effectively reach them.

Particular groups of people are most vulnerable to impacts of climate change, including women, children, single, female-headed households, and the elderly. These groups tend to be most at risk for poverty and have the most tenuous livelihoods. In addition, living in urban slums can exacerbate vulnerability — housing stock and infrastructure is often substandard or non-existent in urban slums, and many are also located in flood plains or low coastal elevation zones where the risks from the impacts of climate change will be the greatest. The factors influencing population vulnerability therefore include location, poverty, demographic characteristics, and extent of protection provided to people by their housing, infrastructure, and social and economic support structures.

Migration or Displacement

The greatest single impact of climate change is likely to be human migration. Millions of people will be displaced by severe coastal weather events, shoreline erosion, coastal flooding, droughts, and agricultural disruption. Already the world is seeing large numbers of environmental refugees as people attempt to deal with changing climatic conditions.

While predictions of the number, characteristics and location of people who would be forced to migrate are still very rudimentary, the number is sure to be large. The international community has focused principally on issues of short- and long-term displacement linked to acute weather related events like hurricanes. Much more research is necessary on the possible links between long term environmental changes, including droughts and flooding, and international migration.

Reproductive Health

Improved reproductive health, including access to voluntary family planning, can help to mitigate climate change, reduce vulnerability to impacts and foster adaptation. Meeting the needs of some 200 million women worldwide who wish to avoid or delay pregnancy would prevent some 23 million unplanned births and 142,000 pregnancy-related deaths. In addition to contributing to eventual population stabilization, women's ability to plan their families can empower them to cope with the realities of a changing climate, including migration in the face of drought, floods and other extreme weather conditions. The contributions of women to addressing the effects of a changing climate are maximized when they are able to plan their pregnancies and protect their reproductive health.