Population and Climate Change

Climate change is humanity’s most critical challenge, and the risks are multiplying. By burning fossil fuels and deforesting vast areas, humans have increased concentrations of greenhouse gases in the atmosphere to levels unprecedented in at least 800,000 years. As a result, the Earth’s average temperature is rising, endangering food security, the availability of fresh water, and human health. Demographic trends play an important role in understanding and confronting the world’s climate crisis.

Regardless of future emissions trends, the warming that has already resulted from the pre-industrial period to the present will continue for hundreds to thousands of years. These changes will continue to impact people in many ways, but specifically in terms of our capacity to use and manage land, adapt to extreme weather events, produce food, and access vital resources like fresh water. Limiting the global temperature rise is imperative to humanity’s survival.

Preventing further climate change requires ending the burning of fossil fuels for energy, industry, and transportation. This is especially imperative for high consuming regions such as Northern America, Europe, Australia, and China. Stopping forest loss, planting new forests, and managing land to conserve soil carbon are additional important steps to limiting warming that both industrialized and developing countries must prioritize.

Climate change is closely linked to population growth. In high-income countries especially, population growth directly causes climate change because each additional person causes significant emissions throughout their lifetime. High consuming lifestyles in the most affluent countries result in much higher per capita emissions than in middle- and low-income countries, where most of the world’s population lives and is projected to grow. In contrast, people living in low-income regions contribute very little to overall emissions but are disproportionately vulnerable to the weather extremes, water stresses, and food production challenges associated with a warming climate. In the center of the spectrum are middle-income countries, home to 75% of the world’s population. In these places, industrialization will increase consumption over the coming decades. Without changes to how economies tend to grow, carbon emissions will rise. One of the many unjust realities of the climate crisis is the unevenness of development trajectories across the world: The very processes of industrialization that have historically facilitated increases in living standards, overall health, and economic growth for affluent nations now also act as environmental threats for which consequences are more immediate and life-threatening than ever before.

Population pressures compound the negative effects of climate change. Both population growth and climate change contribute to resource depletion, economic insecurity, and decreased overall health. Growing populations increase demand for these diminished natural resources, furthering environmental degradation and posing challenges for equitable resource allocation. Additionally, population pressures undermine food security, poverty alleviation, access to education, the status of women, and climate adaptation.

As there is no panacea for combating climate change, a wide variety of options needs to be exercised. An integrated approach includes educating girls and empowering women to make their own childbearing decisions.

Worldwide, many of the same regions that experience high fertility, low economic status, and high climate vulnerability also have a high unmet need for contraceptives and reproductive health services. Recent research from Project Drawdown shows that family planning, together with girls’ education, could prevent emissions of 85 gigatons of CO2 equivalent by 2050—equivalent to what could be achieved by shutting down 22,000 coal-fired power plants.