With 2 billion people to be added to our human ranks by 2050 and an additional 1 billion more by 2100, demographic trends and variables play an important role in understanding and confronting the world’s climate crisis. Population growth, along with increasing consumption, tends to increase emissions of climate-changing greenhouse gases. Rapid population growth worsens the impacts of climate change by straining resources and exposing more people to climate-related risks—especially in low-resource regions.