Ancient Extinction Offers Climate Change Warning

A calamitous event nearly 250 million years ago, known as the Great Dying, wiped out vast amounts of life. Scientists are now suggesting that the loss of plant life was a major contributor, with dire implications for our future.

The Devastating Great Dying Explained

The Great Dying witnessed the extinction of 81% of marine species, 70% of terrestrial vertebrates, a huge number of insects, and numerous plants. This cataclysmic event is believed to have been triggered by extensive volcanic activity in Siberia.

These eruptions created the Siberian Traps lava plain. They ignited oil and coal deposits, and released dangerous emissions like methane. The combination of atmospheric CO2, sulphur dioxide, and methane decimated the ozone layer, unleashed solar radiation, and acidified the oceans.

Evidence from sediment layers reveals the enormous scale of devastation, with studies in South China showing the disappearance of 286 out of 329 marine animals between two sedimentary zones.

Forest Demise Prolonged Warming

While volcanic activity initiated the mass extinction, researchers have long puzzled over the prolonged warming that followed. Unlike other global warming events in Earth’s history, this one lasted for five million years.

A new study in Nature Communications proposes a theory linking the duration to the loss of tropical forests, arguing that the demise of these forests exacerbated the atmospheric situation. Plants play a crucial role in removing and trapping atmospheric carbon dioxide.

Insufficient carbon capture, the paper argues, sealed the fate for many organisms. A recent study published by the World Wildlife Fund found that deforestation accounts for 15% of global greenhouse gas emissions (WWF).

A Dire Warning for Today

Dr. Zhen Xu, lead author from the School of Earth and Environment at the University of Leeds, stated, “Critically, this is the only high temperature event in Earth’s history in which the tropical forest biosphere collapses, which drove our initial hypothesis. Now, after years of fieldwork, analysis and simulations, we finally have the data which supports it.”

The paper’s authors emphasize a crucial lesson, namely that our current loss of tropical rainforests could significantly worsen long-term temperature increases. Scientists warn that we may be approaching a tipping point where the overheating of the planet becomes inevitable.

The paper concludes with a stark warning: “We believe this case study indicates that beyond a certain global temperature, vegetation die-back will occur, and can result in further warming through removal of vegetation carbon sinks. Our study demonstrates that thresholds exist in the Earth system that can accelerate climate change and have the potential to maintain adverse climate states for millions of years, with dramatic implications for global ecosystem behavior.”