Let’s talk trash, just for a few minutes. In the time it takes you to read this pithy blog, more than 14,000 tonnes of waste will be generated: that’s enough to fill the Pentagon in less than a day. More than 1.5 billion tonnes of trash will be generated this year alone. And if you’re inclined to read this blog again in 2025, the amount will have increased to 23,000 tonnes. The annual trash generated at that time will be more than 2.2 billion tonnes a year. That’s enough garbage to fill the Roman Coliseum 730 times, or a line of garbage trucks 900,000 km long, 23 times around the world. Last week’s release of What a Waste: A Global Review of Solid Waste Management summarizes the issue.

Our cities generate enormous amounts of waste, and they’re just getting started – volumes will likely to increase beyond 2100, and we should plan for about a peak volume, four times what we have today. In today’s dollars, annual waste management costs will eventually exceed $1 trillion, and this cost is almost entirely borne by cities (this amount, for example, eclipses any sort of financial contributions to deal with climate change now being discussed within UNFCCC negotiations). Clearly we have a problem. But why is this particularly relevant to the climate change community?