Figuring out the environmental impact of our clothing is notoriously difficult. Estimates of fashion's carbon footprint range from four  to 10 percent of global greenhouse gas emissions due to the difficulty in measuring the industry's vast and impractical supply chain. It is therefore not surprising that many consumers struggle to understand the impact of their own wardrobes, given the lack of available data and the huge variety of materials and production methods used. (EMILY CHAN, British Vogue)