The world’s population will hit 9.3 billion by 2050 and 10.1 billion by 2100, UN experts say. It’s set to reach 7 billion by the end of this year. The UN uses the figures, which depend on fertility expectations, to set up programs to address issues from maternal mortality to climate change, the AP reports. A UN official sees "serious implications" for providing food, water, energy, work, and education to the poorest countries, Bloomberg notes. (More population stories.)