Forests
Like oceans, the world's forests are also massively important carbon sinks that absorb CO2, and then release oxygen. They also tend to be the areas on land with the richest diversity of plant and animal species.
However, forests also contain a valuable commodity – wood – and when forests are cut down, carbon is released rather than absorbed. To add to this problem, as temperatures rise, some of the world's most important tropical rain forests – including large amounts of the Amazon – could dry out and become savannahs rather than forests. This means that not only will they stop absorbing carbon but that they will start emitting rather than absorbing carbon – making climate change even worse.