As the United Nations COP30 climate change conference convenes in Belém, Brazil, the world's attention will turn to the heart of the Amazon rainforest – a region that symbolises both hope and concern in the fight against climate change.

Once considered one of Earth's most vital carbon sinks, the Amazon is now showing troubling signs – satellite observations reveal that parts of this vast ecosystem are no longer absorbing carbon dioxide as they once did. In some areas, the forest has even become a net source of carbon emissions.