Have one fewer child if you want to fight climate change, study says

If you've been chomping at the bit to battle climate change, you can now give those choppers a break and save the world.

A study released Wednesday in Environmental Research Letters points out four "high impact" actions you can take right now to be kinder to Mother Earth.

To start with, do away with your desire to have one more child.

Did you know that would amount to "an average for developed countries of 58.6 tonnes CO2-equivalent (tCO2e) emission reductions per year" per person? (Well, person not born, anyway.)

What's more, an American family that chooses to have one fewer child "would provide the same level of emissions reductions as 684 teenagers who choose to adopt comprehensive recycling for the rest of their lives," the study added.

The folks behind the study went all out on the have-one-fewer-child solution, leaning on another study that "quantified future emissions of descendants based on historical rates, based on heredity." In other words, "half of a child's emissions are assigned to each parent, as well as one quarter of that child's offspring (the grandchildren) and so forth. This is consistent with our use of research employing the fullest possible life cycle approach in order to capture the magnitude of emissions decisions."

Next, commit to living car-free.

It won't lob off CO2 emissions nearly as much as eschewing an extra offspring — just 2.4 tCO₂e saved per year per person — but it still qualifies as "high impact."

Naturally, if one chooses "biking or walking" over car travel, the emissions saved is much higher than if one chooses public transit over car travel, the study says. "But even if the number of kilometers traveled remains constant, it adds, a switch from driving a sedan to taking public transit has been shown to reduce emissions by 26%–76%."

Oh, and "a car-free lifestyle reduces traffic congestion and petroleum dependence and avoids the environmental toxicity issues surrounding electric vehicle production, making it advantageous even in an era of low-emission vehicles."

Want more? Avoid air travel (1.6 tCO₂e saved per roundtrip transatlantic flight) and eat a plant-based diet (0.8 tCO₂e saved per year), the study added.

One additional point the study notes is that teenagers are the ideal target for exacting change in these areas.

"Adolescents can also choose their own diets, can influence family decisions on vacations (e.g. flying vs. staying local) and should be informed of the environmental consequences of family size as they are likely becoming sexually active," the study said. "Though a 50-year-old car owner with an established lifestyle living in the suburbs might be better able to adopt a recommendation to drive a more efficient car, there are qualitative (paradigm shifting of social norms) and quantitative (emissions reduction) reasons for an adolescent to instead receive the high-impact message: 'live car free'."