According to this
For people who are looking for ways to reduce their “carbon footprint,” here’s one radical idea that could have a big long-term impact, some scientists say: Have fewer kids.
Statistical study finds having children has long-term environmental impact. Under current conditions in the United States, for instance, each child ultimately adds about 9,441 metric tons of carbon dioxide to the carbon legacy of an average parent – about 5.7 times the lifetime emissions for which, on average, a person is responsible.
“Many people are unaware of the power of exponential population growth,” Murtaugh said. “Future growth amplifies the consequences of people’s reproductive choices today, the same way that compound interest amplifies a bank balance.”
According to Natasha Gilbert
Access to contraception could tackle global warming, says United Nations.
Thoraya Ahmed Obaid, executive director of the UNFPA, says that countries are probably shy of talking about this link because they fear that the discourse will turn to population control. “We understand these fears,” she says, “but if contraception and family planning were made available to all those who want it, this would slow population growth and have a huge impact on climate change.”
Economic growth is generally believed to be one of the key drivers of lowering fertility rates, but Obaid argues that education and access to family-planning services are more influential on population levels.
Paul van Gardingen, professor of international development at the University of Edinburgh, UK, agrees that the role of education and contraception “is stronger than the relationship between GDP [gross domestic product] and fertility. This is not to say that GDP is not important, but to say it is the thing that will reduce overall fertility and stabilize the global population is a bit tenuous,” he says.
The US has a high GDP, but relatively poor education or access to contraception compared to other developed countries. So the projected population growth of the US is also similar to that of developing countries.
According to this
Between 2009 and 2050, virtually all population growth will take place in the LDCs [less developed countries]. The small amount of population growth projected for MDCs [more developed countries] will be largely accounted for by the United States and Canada. In many MDCs, most growth will likely be due to immigration from LDCs. In the United States, however, natural increase (births minus deaths) still accounts for more than 50 percent of annual population growth.
and the US population is projected to grow from 307 million today to 439 million by 2050.
A person born in the US has a larger carbon footprint than a person born in a developing country. So improving US education and access to contraception could go a long way toward slowing global warming.
Update: Joel Kotkin in The Next Hundred Million points out some of the benefits to the US of the current trend. For example, according to the book review “The more, the better” by Nick Schulz
“In stark contrast to its rapidly aging rivals,” Mr. Kotkin writes in “The Next Hundred Million,” “America’s population is expected to expand dramatically in coming decades.” He points to a slowly rising birth rate and to the continuing in-migration of young workers from poorer countries. Most of America’s population growth between 2000 and 2050, he notes, “will be in its racial minorities, particularly Asians and Hispanics, as well as in a growing mixed-race population.” No other developed country, he says, “will enjoy such ethnic diversity.”
I admit, that sounds great. If the ecosystem survives our growth, America will still be riding high, but that survival is a big if.