We’re always reading about how many billions of tons of carbon dioxide are spit into the atmosphere each year. The concept is difficult to wrap our heads around because, let’s face it, carbon dioxide is a gas (as in soda bubbles), so how do scientists weigh it? In any case, the seven-billion-plus humans on the planet are causing nine-billion-plus tons of CO 2 to contribute to global warming annually. CO 2 output has more than quadrupled in the last 50 years.

According to Jake Abrahamson, writing in the May/June issue of Sierra magazine, CO 2 levels are likely to double again over the next half century. At that point the Greenland ice sheet will start caving in. What, you may ask, is the Greenland ice sheet? It is a sheet of thick ice that covers most of Greenland. If it melts, the world’s oceans would likely rise about 22 feet. If that happens, people will be buying beachfront property in Tennessee.

What, pray tell, could we do to stop this headlong drive to crash ourselves into an environmental brick wall? How about, say, family planning? Right now the world grows by more than the population of Akron, Ohio each day. Akron has about 218,000 people. Put another way, we need to accommodate the equivalent of another mid-size city – population-wise – each day! Housing, schools, transportation, roads, food, waste disposal, consumer supplies, the whole shebang . . . every day!

Abrahamson contends that a concerted, worldwide family planning campaign can do as much to reduce emissions as conserving electricity, trapping carbon, or using alternative fuels. What if we were to initiate five strategies to slow population growth?

Photo: Marie Stopes International The U.N. Population Fund (UNFPA) estimates there are 215 million women who would like access to contraceptives but cannot get them for various reasons. Contraceptives for these women would reduce unintended pregnancies from the current 76 million to 22 million, annually.

Women who benefit from literacy tend to have smaller families (with the bonus of lower child mortality rates). They are also less likely to bear children before they can afford to.

Comprehensive sex education would limit teen pregnancy rates. We have discussed the impact of consumer consumption frequently in this venue. Nearly half of the world’s population is under age 25. The reproductive decisions and behaviors of the current generation of young adults will reverberate for decades. According to Abrahamson, by having a child, an American woman increases her CO 2 footprint sixfold.

Where women lack essential human rights, they lack control over their own fecundity. Gender equality, including suffrage, education and control over women’s own bodies, has to be taught to cultures that value male dominance. This is no easy task, but it has happened all over the globe.

“Where welfare is tied directly to the land, aid groups are promoting a development approach called population, health and environment (PHE), which integrates improved access to health services, with models for sustainable resource use.” This dynamic development is most important for societies in tropical wilderness area.

The Sierra article compares these population efforts with eight other CO 2 -reducing goals:

Replacing oil and gas with renewable energy sources;

Cut consumer power use by 25 percent;

Run cars on clean hydrogen;

Double vehicle fuel economy;

Replace coal with solar energy;

Replace coal with wind;

Practice conservation tillage;

Stop deforestation.

In our book, Enough of Us: Why we should think twice before making children, we direct our case at the United States. But as far as worldwide reform goes, we see little chance of wholesale reform without America taking the lead. We must lead both by example and by reaching out to people all over the globe, with both education and money. Even while our own economy is struggling mightily, we must make the effort or future generations will suffer the consequences of our lack of foresight.

We Americans have the knowledge and the means. Now we must muster the will. At seven billion, there are lots more than enough of us.