New modeling based on fossil plant records suggests the collapse of tropical forests at the end of the Permian, about 252 million years ago, kept Earth in a hothouse state for roughly five million years. Researchers from the University of Leeds and the China University of Geosciences mapped plant productivity before and after the extinction, then fed those maps into an Earth-system model. They found that when the forests disappeared, natural carbon removal slowed sharply, and CO2 stayed near 7,000 parts per million while equatorial temperatures held around 33 to 34°C. The study points to two linked mechanisms: dead vegetation no longer builds up peat and coal, and roots no longer accelerate the rock weathering that pulls CO2 out of the air. The authors estimate that land carbon uptake fell about 70 percent in the earliest Triassic. They stress the recovery clock ran in millions of years, and the article draws a direct line to present-day tropical forest loss and the risk of Amazon tipping points. For anyone tracking carbon markets or climate policy, the takeaway is that keeping existing forest sinks intact is mitigation, not an optional extra.
