Alexandra Olson

UNITED NATIONS (AP) — The United Nations forecast Thursday that the world's population will increase from 7.2 billion today to 8.1 billion in 2025, with most growth in developing countries and more than half in Africa. By 2050, it will reach 9.6 billion.

SANDAG's regional growth forecast for San Diego through 2050.

"This figure shows worldwide greenhouse gas emissions by sector from 1990 to 2010. For consistency, emissions are expressed in million metric tons of carbon dioxide equivalents. These totals include emissions and sinks due to land-use change and forestry.

Mark Tran, The Guardian

UN special rapporteur on the right to food champions agroecology as sustainable alternative to existing framework

Lauren Riga

As the world is undergoing the largest wave of urban growth in history, increasing from approximately 3.4 billion in 2009 to 6.4 billion in 2050

Poverty will be a main problem in this country. In about 20 years, there will be an increase in active population. The same thing will happen to other developing countries where there won't enough jobs for the active population and a much higher unemployment rate.

With technology improving, life expectancy will increase. In about 20 years, the active population of 2010, aka the baby boomers, will shift up, increasing the inactive population. The same thing will happen to many other developed countries where the level of dependency will increase which means there will not be enough active workers to support the elderly.

Robert Engelman

Although most analysts assume that the world’s population will rise from today’s 7 billion to 9 billion by 2050, it is quite possible that humanity will never reach this population size.

This graph is showing the impact of AIDS on South africa population

World population growth rate showing the declining rate throughout the years.