It is a huge and desperately needed idea in an age of scarce resources and a planet undergoing climate change. Of that total, 1,900 have already been emitted by 2011: as of 2010 there were around 49 Gt emitted per year (IPCC, 2014). According to McGlade & Ekins (2015, p.187), [i]t has been estimated that to have at least a 50 per cent chance of keeping warming below 2°C throughout the twenty-first century, the cumulative carbon emissions between 2011 and 2050 need to be limited to around 1,100 gigatonnes of carbon dioxide. [