Nations that emit the most greenhouse gases would have the most responsibility for overshooting the 1.5C goalschankz/ShutterstockEach country should be held responsible for how much it is to blame when the world overshoots the 1.5C warming limit by assigning a net-zero carbon debt if it has pumped out more than its fair share of emissions, a team of climate scientists is proposing.The aim is to encourage those with greater responsibility for the overshoot to make amends by, say, removing carbon dioxide from the atmosphere or helping other countries reach net-zero faster.