As the human population of the Earth hits 7 Billion, welcome to the Anthropocene era. Scientists are no longer classifying our timescale on geological criteria but instead using the long-term alteration of the natural world by humanity.
We now occupy or manipulate most of the land in nearly every continent except Antartica and are steadily killing off or emptying vast tracts of the oceans. We appropriate anywhere from 24 percent to nearly 40 percent of the photosynthetic output of the planet for our food and other purposes, and more than half of its accessible renewable freshwater runoff.
Space is not the problem, we could all fit into Greater London with room to move. It is because our population is so large and growing so fast that we must care, ever more with each generation, how much we as individuals are out of sync with environmental sustainability. Our diets, our acquisition of new technology, our means of transport, and our urge to keep interior temperatures close to 22C no matter what is happening outside, doesn’t make us bad people, but the collective effect on our planet is simply not sustainable.Action means doing a lot of different things right now. We can't stop the growth of our numbers in any acceptable way immediately. But we can put in place conditions that will support an early end to growth, possibly making this year's the last billion-population day we ever mark.
Simultaneously, we need a swift transformation of energy, water, and materials consumption through conservation, efficiency, and green technologies. We shouldn't think of these as a sequence of efforts, dealing with consumption first, because population dynamics take time to turn around, but as simultaneous work on multiple fronts.
