The Physical Science Basis, AR6

The first of the sixth round of IPCC Assessment Reports focuses on the realities of climate change but it makes that carbon removals are urgently needed – and that planting trees alone won’t do it. It estimates the remaining carbon budget for a 1.5DC scenario at 400-500 billion tonnes of CO2 from the start of 2020, with human activities currently emitting around 40 billion tonnes of CO2 each year. Within this decade, in other words, annual carbon removals equal to or greater than annual emissions are needed to stabilise or ideally reverse aspects of climate change.