The world's population is projected to reach 8 billion on Tuesday, according to the United Nations. It took 12 years for the global population to grow to that level from 7 billion.
The UN attributed the growth to "improvements in public health, nutrition, personal hygiene and medicine," but also noted that it's the world's poorest countries -- most of them in sub-Saharan Africa -- that are more likely to have the highest fertility rates. Continued rapid population growth in those countries, the UN said in a release, could thwart efforts to achieve sustainable development, blocking "the world's best pathway toward a happy and healthy future."
Meanwhile, rising income levels are a predominant driver of rapid climate change, the UN said. It's the countries with higher per capita income, not the countries with rapid population growth, that consume the most material resources and produce the most greenhouse gas emissions that are driving the climate crisis.
Those richer nations have a responsibility to cut back on "unsustainable patterns of production and consumption," the UN indicated, if they're to meet Paris Agreement goals for combating the climate crisis as the world grapples rising sea levels, warming temperatures and dangerous new weather patterns.
It will be another 15 years, or until sometime in 2037, before the global population is projected to reach 9 billion.