It is always difficult to encapsulate a 12-month period, let alone the 365 turbocharged 24-hour news cycles that seem to have become the new normal. So much happens in the course of a year — from governments, companies, activists and many others — that it all becomes a blur. That certainly is true in the world of sustainability. From the launch of Loop, the circular economy wunderkind, in January to the colossal failure of COP25 in December, from the burning Arctic and Amazon to the dizzyingly weird weather, it’s another year of ups and downs, reasons for both optimism and despair.