How the demographic transition interacts with the climate crisis is complex and murky. Little research has been done on the topic, and the demographic data are very macro. Most evidence is anecdotal. In Laura Spinney’s article “Why declining birth rates are good news for life on Earth” she writes how fertility rates are falling globally.
Some women don’t want to bring children into the world, children whose lifetime carbon footprints will only exacerbate conditions on a planet that already emits too many greenhouse gases. Others hesitate to give birth to children who will face difficult if not intolerable living conditions as they age. They want to spare them a struggle to survive in a hostile environment.
Alternately, the media raises false alarms about declining sperm counts, lower fertility rates, an ageing population, and — horrors! — depopulation. Religious pro-natalists chant the sanctity of life and extoll the precept of ‘Be fruitful and multiply’; they silently valorize the increase in their number, power, and prestige, while remaining indifferent to the quality of life those children will have.
When the dominant if rarely acknowledged paradigm is growth, as it is with capitalism, children are necessary and valued highly. However, the resources of the Earth are finite, so ultimately the paradigm is unsustainable. We humans have reached that point in numbers, development, and rapacity. We now need to adopt a new paradigm: sustainability. The maternal parity rate for a steady population is about 2.1 births per mother. Fertility rates close to 2 are sustainable. The demographic transition from high infant mortality, high fertility, to low infant mortality, low fertility that began over 200 years ago with better nutrition and the beginning of medical science, continues to this day. As women become healthier, more educated, have more options, and more of their children survive to adulthood, they will continue to have fewer children. Mostly, that’s better for everyone, for the climate, and for the sustainability of life on Earth.