June 19, 2017

The most ignored factor in climate change

LA Times, 2015 - Earlier this month, Pope Francis made news when he said that not only was climate change real, but it was mostly man-made. Then, last week, he said that couples do not need to breed “like rabbits” but rather should plan their families responsibly — albeit without the use of modern contraception.

Though the pope did not directly link the two issues, climate scientists and population experts sat up and took notice. That's because for years, they have quietly discussed the links between population growth and global warming, all too aware of the sensitive nature of the topic. Few of them can forget the backlash after then-Secretary of State Hillary Rodham Clinton said in 2009 that it was strange to talk about climate change without mentioning population and family planning. Critics immediately suggested that she was calling for eugenics, thus shutting down the conversation and pushing the issue back into the shadows. The pope's support of smaller families might help that discussion come back into the light, where it belongs.

Biological Diversity - Sensitive subject or not, the reality is that unsustainable human population growth is a potential disaster for efforts to cut greenhouse gas emissions. These days, the biggest population growth is occurring in developing nations, which is why any discussion must be sensitive to the perception that well-off, industrialized nations — the biggest climate polluters, often with majority-white populations — might be telling impoverished people of color to reduce their numbers. In fact, person for person, reducing birth rates in industrialized nations has a bigger impact on greenhouse gas emissions because affluent people use more of the Earth's resources and depend more heavily on fossil fuels.

The largest single threat to the ecology and biodiversity of the planet in the decades to come will be global climate disruption due to the buildup of human-generated greenhouse gases in the atmosphere. People around the world are beginning to address the problem by reducing their carbon footprint through less consumption and better technology. But unsustainable human population growth can overwhelm those efforts, leading us to conclude that we not only need smaller footprints, but fewer feet.

Portland, Oregon, for example, decreased its combined per-capita residential energy and car driving carbon footprint by 5 percent between 2000 and 2005. During this same period, however, its population grew by 8 percent.

A 2009 study of the relationship between population growth and global warming determined that the “carbon legacy” of just one child can produce 20 times more greenhouse gas than a person will save by driving a high-mileage car, recycling, using energy-efficient appliances and light bulbs, etc. Each child born in the United States will add about 9,441 metric tons of carbon dioxide to the carbon legacy of an average parent. The study concludes, “Clearly, the potential savings from reduced reproduction are huge compared to the savings that can be achieved by changes in lifestyle.”

Scientific American -  No doubt human population growth is a major contributor to global warming, given that humans use fossil fuels to power their increasingly mechanized lifestyles. More people means more demand for oil, gas, coal and other fuels mined or drilled from below the Earth’s surface that, when burned, spew enough carbon dioxide (CO2) into the atmosphere to trap warm air inside like a greenhouse.

According to the United Nations Population Fund, human population grew from 1.6 billion to 6.1 billion people during the course of the 20th century. (Think about it: It took all of time for population to reach 1.6 billion; then it shot to 6.1 billion over just 100 years.) During that time emissions of CO2, the leading greenhouse gas, grew 12-fold. And with worldwide population expected to surpass nine billion over the next 50 years, environmentalists and others are worried about the ability of the planet to withstand the added load of greenhouse gases entering the atmosphere and wreaking havoc on ecosystems down below.

“Population, global warming and consumption patterns are inextricably linked in their collective global environmental impact,” reports the Global Population and Environment Program at the non-profit Sierra Club. “As developing countries’ contribution to global emissions grows, population size and growth rates will become significant factors in magnifying the impacts of global warming.”


Boffin said...

The antidote to overpopulation is prosperity (and female education).

Pretty generally around the world fertility drops - and drops dramatically - with economic development and prosperity.

The wrong thing to do is lock regions, cultures, and countries into poverty with "green" thinking. That's a recipe for continuous misery.

Anonymous said...

Education for women is more important than prosperity for lowering birth rates. There are enough cases in development work where simply educating women has led to dramatic reductions of family size. Women's education is usually the foundation of prosperity for these communities. Another aspect of this is terminology, in locations where family planning is an urgent need, but large families are valued, it's better to talk about birth control as child spacing. Teaching women how to avoid pregnancy until it's desired isn't as disruptive to the culture as saying "don't have children". Child spacing can achieve much of what population control hopes to accomplish, without threatening people and their traditions. A woman who child spaces may still have 3-4 children, but that is a huge improvement over women having much larger families that they cannot feed and health risks to the mother for not taking a break from being pregnant.