How The World Is Changing After Its Population Hit 8 Billion

Much of the worlds population growth has come in the last century as better living standards and health advancements extended life expectancy.

The world's population reached 8 billion Tuesday, according to estimates from the United Nations, even as the international body said that a surge in births in lower income countries is likely to create risks.

Here's what it means for the next few decades:

Slowing Population Growth

Much of the world's population growth has come in the last century as better living standards and health advancements extended life expectancy, with the total number of people on earth growing from just 2 billion in 1927 to 6 billion by 1998. Still, there are early signs that this surge is slowing.