UPDATE: 2020-12-16 The world’s human population is as of today 7.8 billion, almost 8 billion.
UPDATE: 2011-10-31 There are officially now 7 billion people on the planet. You can see them all here – http://www.7billionworld.com/ This is, of course, just a best guess, and I demand a recount!
The United Nations estimates that the world population will reach 7 billion (that’s 7,000,000,000 even in the UK where the old definition of a billion (as a million squared) was abandoned under US pressure years ago). The UN data is based on best estimates but obviously cannot be 100% accurate. Your neighbour’s newborn hasn’t been registered yet, neither has the death of the old guy down the road, multiply at least once or twice per neighbourhood and I suspect that we could not possibly know the world population to at least +/- 10 million or so. Setting aside the fact that we don’t have an ongoing world census…
Nevertheless, the “official” data suggest that, at the time of writing, we have just under 10 hours (at 08h00 GMT, 2011-10-31) before we click past the 7 billion mark. The US census suggests we won’t actually reach 7 billion until April 2012, which gives an error margin of 10 million, as I suggested, if there are approximately 70000 more people on the planet each day.
Why is the number relevant? Well, it puts into stark relief the potential impact humanity can have on the world. In 1999, there were “just” 6 billion people. The world population has doubled since the year I was born. (In pseudofact, I was the 3,500,000,000th person alive on the day of my birth). It’s just a number, but it’s a big number and emphasises once again that we can no longer think of the planet in terms of the first, second, and third world. There really is just one world, with limited resources, oceans and atmosphere all interconnected and a single species (that has amounted to almost 100 billion people since our species emerged) that seems to hold the key to the survival of countless others.