In the quest to address humanity’s most pressing challenges, scientists often turn to nature for inspiration. When it comes to tackling global warming, the study of Earth’s geological history provides a valuable long-term perspective.
Throughout history, catastrophic volcanic eruptions have released massive amounts of carbon into the atmosphere and oceans, leading to rapid climate warming and mass extinctions. These events may have also disrupted carbon-climate regulation systems for millions of years, emphasizing the importance of understanding geological history in addressing climate change.
Earth and environmental scientists from ETH Zurich, in collaboration with researchers from the University of Arizona, University of Leeds, CNRS Toulouse, and the Swiss Federal Institute for Forest Snow and Landscape Research (WSL), conducted a groundbreaking study on the impact of major climatic shifts on vegetation and Earth’s natural carbon-climate regulation system.
By analyzing isotopes in sediments and using a specially designed model to simulate vegetation’s role in the geological climate system, the research team investigated how the Earth system responds to significant carbon release from volcanic events. The study focused on three major climatic shifts in geological history, including the Permian-Triassic mass extinction caused by the Siberian Traps event around 252 million years ago.
“The Siberian Traps event released some 40,000 gigatons (Gt) of carbon over 200,000 years. The resulting increase in global average temperatures between 5 – 10°C caused Earth’s most severe extinction event in the geologic record,” ETH Zurich professor Taras Gerya said.
“The recovery of vegetation from the Siberian Traps event took several millions of years, and during this time, Earth’s carbon-climate regulation system would have been weak and inefficient, resulting in long-term climate warming,” explains lead author Julian Rogger, ETH Zurich.
The severity of such events is directly linked to the speed at which emitted carbon is removed from Earth’s atmosphere through processes like silicate mineral weathering or organic carbon production. This crucial removal of carbon plays a significant role in shaping the impact of these events.
Furthermore, the duration for the climate to stabilize is influenced by how quickly vegetation adapts to rising temperatures. Some species evolve, while others migrate to cooler regions. However, in instances of catastrophic geological events, plant species may not have adequate time to adjust to prolonged temperature increases. This leads to long-lasting consequences, leaving a lasting imprint on the climate for thousands, or even millions, of years.
The study reveals that disruptions to vegetation have led to prolonged and intensified periods of climate warming in the past. This finding underscores the vital role of vegetation in regulating Earth’s climate and emphasizes the potential long-term impact of human-induced changes to natural systems. It’s a compelling reminder of the importance of preserving and protecting our planet’s ecosystems.
“Today, we find ourselves in a major global bioclimatic crisis,” comments Loïc Pellissier, Professor of Ecosystems and Landscape Evolution at ETH Zurich and WSL. “Our study demonstrates the role of the functioning of vegetation in recovering from abrupt climatic changes. We are currently releasing greenhouse gases at a faster rate than any previous volcanic event. We are also the primary cause of global deforestation, which strongly reduces the ability of natural ecosystems to regulate the climate. This study, in my perspective, serves as a ‘wake-up call’ for the global community.”
Journal reference:
- Julian Rogger, Emily J. Judd, Benjamin J. W. Mills, Yves Goddéris, Taras V. Gerya, Loïc Pellissier. Biogeographic climate sensitivity controls Earth system response to large igneous province carbon degassing. Science, 2024; DOI: 10.1126/science.adn3450
