Going into debt with nature is a dangerous thing. When our stocks of water, land and clean air are spent – we don’t have a second planet to borrow from. But that’s exactly the way that Earth is heading. 1 August 2018 marks an annual event, “Earth Overshoot Day”: the day on which the natural resources the planet can regenerate within one year are exhausted. This is the earliest date on which Earth Overshoot Day has ever been reached.