Why a 2.5 tonne target?

The world is already warming and the climate is changing. However, limiting global warming to 1.5C will significantly reduce the risks and impacts of climate change. 

2.5 tonnes is important because it is the amount of carbon that the average person globally should be emitting by 2030 that is consistent with 1.5C of warming. It is based on estimates from the UN about the amount of carbon budget we all have left.