U.S. Population Predicted to Boom by 2050

WASHINGTON, DC, August 18, 2004 (ENS) - With 294 million people, the United States is now the world's third most populous country after China and India. According to a new forecast from the Population Reference Bureau, the U.S. population will increase by 45 percent over the next 45 years, the only industrialized nation projected to experience a major population increase.

The total world population will likely reach 9.3 billion by mid-century, up from the 6.3 billion people on Earth today.

Times Square, New York City (Photo courtesy FreeFoto)

This population increase, made up of a combination of an increasing birth rate and increasing immigration, will result in a population density of 79 people per square mile by 2050, the Population Reference Bureau (PRB) predicts.

This will put pressure on all U.S. natural resources - water, agricultural land, fuel, timber, fisheries - and living space.

According to the PRB forecast, which is based recent census or official national and United Nations data, all regions of the world except Europe will continue to grow. Developing countries in Africa and Asia will account for about 90 percent of the increase in world population projected by 2050, while the populations of most developed countries will decrease.

New houses under construction in Longmont, Colorado (Photo by Warren Gretz courtesy NREL)

For example, Western European populations will shrink, while Western Asian nations are expected to gain about 186 million people by 2050, says Carl Haub, who heads the Population Reference Bureau.

"The demographic contrasts between Japan and Nigeria, two countries with roughly equal population sizes today, illustrate the differing challenges faced by rich and poor countries," said Haub.

Whereever the population is increasing, there will be an increase in demand for water. A University of New Hampshire study has found that population growth and economic development, in tandem with global climate change, will impact the availability of fresh water over the first quarter of this century.

The research reveals that climate change accounts for 20 percent of the impending increase in water scarcity, whereas population change and economic development account for the remaining 80 percent.

This week's drought map from the U.S. Department of Agriculture's Drought Monitor shows nearly half the country is experiencing drought conditions. (Map courtesy USDA)

Published in the July 14 issue of the journal "Science," the four UNH authors conclude that nearly two billion people currently suffer from severe water scarcity, a far higher estimate than from previous assessments. According to current United Nations estimates, 1.1 billion people do not have sufficient safe water.

An additional one billion are expected to face water scarcity by the year 2025 due to increasing population and global climate change, says lead author Charles Vorosmarty, research associate professor in UNH's Institute for the Study of Earth, Oceans, and Space.

Vorosmarty says that, while the scientific community has increased its resources devoted to the study of global climate change, the "human issue" has received far less attention. He says it will be necessary to consider how climate change and climate extremes interact with surface and groundwater, as well as how humans respond and adapt to water stress. These adaptations will involve costly investment in infrastructure like sewage treatment plants, reservoirs and irrigation.

"In light of this research," says co-author Richard Lammers, UNH research scientist, "one of my concerns is that this combination of climate and population change could drive various regions into water related conflict."

"We're really not prepared for global climate change if we don't pay attention to population growth," said Lammers. "It makes sense to study and get ready for both."