Latest news with #PermianTriassic
Yahoo
08-07-2025
- Science
- Yahoo
Climate tipping point might have been crossed before the ‘Great Dying'
If you purchase an independently reviewed product or service through a link on our website, BGR may receive an affiliate commission. One of the most notable extinction events in Earth's history has provided us with a new discovery. Recently discovered fossils from the time period known as the 'Great Dying' have revealed that the climate tipping point had likely already been crossed before the event began. The Great Dying, which is scientifically known as the Permian-Triassic Mass Extinction, took place roughly 252 million years ago. This event led to the extinction of most marine species, as well as significant declines in land-based plants and animals. While the event is usually attributed to extreme global warming caused by a period of volcanic activity, scientists have always been perplexed about why the intense greenhouse conditions continued for roughly five million years after the extinction event. Today's Top Deals XGIMI Prime Day deals feature the new MoGo 4 and up to 42% off smart projectors Best deals: Tech, laptops, TVs, and more sales Best Ring Video Doorbell deals According to the fossils discovered from the time period, scientists may have found their answer. Based on the findings, which the researchers have published in Nature Communications, the demise and slow recovery of tropical forests from the time period limited what we call carbon sequestration. This is the process where carbon dioxide is removed from the atmosphere and held in plants and the soil. It's vital to controlling the state of the climate across our planet. Without this process, carbon dioxide couldn't be removed as stably from the atmosphere, allowing it to continue building up. This resulted in prolonged periods where high levels of carbon dioxide existed in the atmosphere. As such, the researchers believe the climate tipping point had already been crossed before the volcanic activity that fostered the event actually began. This is the only high-temperature event in Earth's history that we know of where the important biosphere found in the tropical forest collapsed. That's why the researchers began going down this path of study in the first place. And after years of collecting data and looking at fossil records, the researchers finally have the data to back up the hypothesis. This belief also seems to back up the idea that there are various tipping points, or thresholds, that exist in the Earth's climate-carbon system. And when these tipping points are reached—similarly to how we have come close to them now—global warming can be amplified greatly. If the tipping point had been reached, then it could have helped spur along the volcanic activity to which researchers often attribute the event's beginning. What we do with this data, though, is up to the researchers. It could be vital to understanding the state of our own fight against climate change, as well as the possibility of whether or not we'll be able to stop ourselves from crossing the tipping point again. More Top Deals Memorial Day security camera deals: Reolink's unbeatable sale has prices from $29.98 See the
Yahoo
04-07-2025
- Science
- Yahoo
'The Great Dying' mass extinction was a warning from the trees, study says
It happened before, and could happen again…. That's the message in a new study about the catastrophic collapse of Earth's tropical forests due to natural volcanic causes 252 million years ago. The collapse of tropical forests was the primary cause of the prolonged global warming that followed, according to a new study published July 2 in the British journal Nature Communications. This coincided with a mass extinction, likely the worst in Earth's history. 'There is a warning here about the importance of Earth's present-day tropical forests," study co-author and University of Leeds professor Benjamin Mills said, in a statement: "If rapid warming causes them to collapse in a similar manner, then we should not expect our climate to cool to preindustrial levels, even if we stop emitting CO2. 'Indeed, warming could continue to accelerate in this case even if we reach zero human emissions. We will have fundamentally changed the carbon cycle in a way that can take geological timescales to recover, which has happened in Earth's past.' The huge climate changes back then occurred during the Permian–Triassic Mass Extinction – sometimes referred to as the "Great Dying," which happened around 252 million years ago, leading to the massive loss of marine species and significant declines in terrestrial plants and animals. The event has been attributed to intense global warming triggered by a period of volcanic activity in Siberia, known as the Siberian Traps, the study says. This rapid increase in carbon dioxide in Earth's atmosphere and the resulting temperature increase is thought to be the primary kill mechanism for much of life at the time, according to the Conversation. However, scientists had been unable to pinpoint why super-greenhouse conditions persisted for around five million years afterwards. Now, in the new study, researchers have gathered data that supports the theory that the demise of tropical forests, and their slow recovery, limited carbon sequestration – a process where carbon dioxide is removed from the atmosphere and held in plants, soils or minerals. Our current understanding is that it was high temperatures which resulted from huge volcanic carbon dioxide emissions over thousands of years, Mills said in an e-mail to USA TODAY. "This volcanic event is called the Siberian Traps and may be the biggest to ever have occurred." "Yes," Mills said, adding that the climate had already warmed, which initially caused the tropical forests to die back, but the removal of forests took away one of the planet's most important carbon removal processes – photosynthesis. The lack of this "carbon sink" caused CO2 levels to build up even further, which drove excess warming. "While the climate is currently warming (and is doing so faster than during the event 252 million years ago), we are not yet at the temperature where tropical forests are expected to reach a tipping point and transition into a carbon source rather than sink," Mills told USA TODAY. "So it is not happening now, but we may not be that far away." We have warmed the planet by about 1 degree C since the Industrial Revolution, and estimates for Amazon rainforest tipping points range from 2 to 6 degrees C. It is hard to estimate this accurately. The Triassic super-greenhouse took thousands of years to establish, but because we are emitting carbon dioxide much more quickly than in the deep past, we might expect effects to begin to occur "over hundreds of years," Mills said. "To see 'super greenhouse' conditions we would need to remove almost all of the tropical forested area. It is debatable whether this could occur in the present day where the plants are different, and the shape of the continents is different than in the past. But personally I do not want us to run this experiment!" Speaking about the new study, co-author Jianxin Yu of the China University of Geosciences added: 'Let's make sure our work transcends academia: it is a responsibility to all life on Earth, today and beyond." "Earth's story is still being written, and we all have a role in shaping its next chapter," Yu said. This article originally appeared on USA TODAY: Forest loss fueled 'Great Dying' mass extinction, study says
The Independent
03-07-2025
- Science
- The Independent
Fossils reveal why earth was extremely hot for millions of years
Some 252 million years ago, almost all life on Earth disappeared. Known as the Permian–Triassic mass extinction – or the Great Dying – this was the most catastrophic of the five mass extinction events recognised in the past 539 million years of our planet's history. Up to 94 per cent of marine species and 70 per cent of terrestrial vertebrate families were wiped out. Tropical forests – which served, as they do today, as important carbon sinks that helped regulate the planet's temperature – also experienced massive declines. Scientists have long agreed this event was triggered by a sudden surge in greenhouse gases which resulted in an intense and rapid warming of Earth. But what has remained a mystery is why these extremely hot conditions persisted for millions of years. Our new paper, published in Nature Communications, provides an answer. The decline of tropical forests locked Earth in a hothouse state, confirming scientists' suspicion that when our planet's climate crosses certain 'tipping points', truly catastrophic ecological collapse can follow. A massive eruption The trigger for the Permian–Triassic mass extinction event was the eruption of massive amounts of molten rock in modern day Siberia, named the Siberian Traps. This molten rock erupted in a sedimentary basin, rich in organic matter. The molten rock was hot enough to melt the surrounding rocks and release massive amounts of carbon dioxide into Earth's atmosphere over a period as short as 50,000 years but possibly as long as 500,000 years. This rapid increase in carbon dioxide in Earth's atmosphere and the resulting temperature increase is thought to be the primary kill mechanism for much of life at the time. On land it is thought surface temperatures increased by as much as 6°C to 10°C – too rapid for many life forms to evolve and adapt. In other similar eruptions, the climate system usually returns to its previous state within 100,000 to a million years. But these 'super greenhouse' conditions, which resulted in equatorial average surface temperatures upwards of 34°C (roughly 8°C warmer than the current equatorial average temperature) persisted for roughly five million years. In our study we sought to answer why. The forests die out We looked at the fossil record of a wide range of land plant biomes, such as arid, tropical, subtropical, temperate and scrub. We analysed how the biomes changed from just before the mass extinction event, until about eight million years after. We hypothesised that Earth warmed too rapidly, leading to the dying out of low- to mid-latitude vegetation, especially the rainforests. As a result the efficiency of the organic carbon cycle was greatly reduced immediately after the volcanic eruptions. Plants, because they are unable to simply get up and move, were very strongly affected by the changing conditions. Before the event, many peat bogs and tropical and subtropical forests existed around the equator and soaked up carbon. However, when we reconstructed plant fossils from fieldwork, records and databases around the event we saw that these biomes were completely wiped out from the tropical continents. This led to a multimillion year 'coal gap' in the geological record. These forests were replaced by tiny lycopods, only two to 20 centimetres in height. Enclaves of larger plants remained towards the poles, in coastal and in slightly mountainous regions where the temperature was slightly cooler. After about five million years they had mostly recolonised Earth. However these types of plants were also less efficient at fixing carbon in the organic carbon cycle. This is analogous in some ways to considering the impact of replacing all rainforests at present day with the mallee-scrub and spinifex flora that we might expect to see in the Australian outback. Finally, the forests return Using evidence from the present day, we estimated the rate at which plants take atmospheric carbon dioxide and store it as organic matter of each different biome (or its 'net primary productivity') that was suggested in the fossil record. We then used a recently developed carbon cycle model called SCION to test our hypothesis numerically. When we analysed our model results we found that the initial increase in temperature from the Siberian Traps was preserved for five to six million years after the event because of the reduction in net primary productivity. It was only as plants re-established themselves and the organic carbon cycle restarted that Earth slowly started to ease out of the super greenhouse conditions. Maintaining a climate equilibrium It's always difficult to draw analogies between past climate change in the geological record and what we're experiencing today. That's because the extent of past changes is usually measured over tens to hundreds of thousands of years while at present day we are experiencing change over decades to centuries. A key implication of our work, however, is that life on Earth, while resilient, is unable to respond to massive changes on short time scales without drastic rewirings of the biotic landscape. In the case of the Permian–Triassic mass extinction, plants were unable to respond on as rapid a time scale as 1,000 to 10,000 years. This resulted in a large extinction event. Overall, our results underline how important tropical and subtropical plant biomes and environments are to maintaining a climate equilibrium. In turn, they show how the loss of these biomes can contribute to additional climate warming – and serve as a devastating climate tipping point. Zhen Xu was the lead author of the study, which was part of her PhD work. Andrew Merdith is a DECRA Fellow at the School of Earth Sciences, University of Adelaide. Benjamin J. W. Mills is a Professor of Earth System Evolution at the University of Leeds. Zhen Xu is a Research Fellow at the School of Earth and Environment, University of Leeds.
The Independent
03-07-2025
- Science
- The Independent
Fossils unlock 250-million-year-old mystery of the ‘Great Dying'
Some 252 million years ago, almost all life on Earth disappeared. Known as the Permian–Triassic mass extinction – or the Great Dying – this was the most catastrophic of the five mass extinction events recognised in the past 539 million years of our planet's history. Up to 94 per cent of marine species and 70 per cent of terrestrial vertebrate families were wiped out. Tropical forests – which served, as they do today, as important carbon sinks that helped regulate the planet's temperature – also experienced massive declines. Scientists have long agreed this event was triggered by a sudden surge in greenhouse gases which resulted in an intense and rapid warming of Earth. But what has remained a mystery is why these extremely hot conditions persisted for millions of years. Our new paper, published in Nature Communications, provides an answer. The decline of tropical forests locked Earth in a hothouse state, confirming scientists' suspicion that when our planet's climate crosses certain 'tipping points', truly catastrophic ecological collapse can follow. A massive eruption The trigger for the Permian–Triassic mass extinction event was the eruption of massive amounts of molten rock in modern day Siberia, named the Siberian Traps. This molten rock erupted in a sedimentary basin, rich in organic matter. The molten rock was hot enough to melt the surrounding rocks and release massive amounts of carbon dioxide into Earth's atmosphere over a period as short as 50,000 years but possibly as long as 500,000 years. This rapid increase in carbon dioxide in Earth's atmosphere and the resulting temperature increase is thought to be the primary kill mechanism for much of life at the time. On land it is thought surface temperatures increased by as much as 6°C to 10°C – too rapid for many life forms to evolve and adapt. In other similar eruptions, the climate system usually returns to its previous state within 100,000 to a million years. But these 'super greenhouse' conditions, which resulted in equatorial average surface temperatures upwards of 34°C (roughly 8°C warmer than the current equatorial average temperature) persisted for roughly five million years. In our study we sought to answer why. The forests die out We looked at the fossil record of a wide range of land plant biomes, such as arid, tropical, subtropical, temperate and scrub. We analysed how the biomes changed from just before the mass extinction event, until about eight million years after. We hypothesised that Earth warmed too rapidly, leading to the dying out of low- to mid-latitude vegetation, especially the rainforests. As a result the efficiency of the organic carbon cycle was greatly reduced immediately after the volcanic eruptions. Plants, because they are unable to simply get up and move, were very strongly affected by the changing conditions. Before the event, many peat bogs and tropical and subtropical forests existed around the equator and soaked up carbon. However, when we reconstructed plant fossils from fieldwork, records and databases around the event we saw that these biomes were completely wiped out from the tropical continents. This led to a multimillion year 'coal gap' in the geological record. These forests were replaced by tiny lycopods, only two to 20 centimetres in height. Enclaves of larger plants remained towards the poles, in coastal and in slightly mountainous regions where the temperature was slightly cooler. After about five million years they had mostly recolonised Earth. However these types of plants were also less efficient at fixing carbon in the organic carbon cycle. This is analogous in some ways to considering the impact of replacing all rainforests at present day with the mallee-scrub and spinifex flora that we might expect to see in the Australian outback. Finally, the forests return Using evidence from the present day, we estimated the rate at which plants take atmospheric carbon dioxide and store it as organic matter of each different biome (or its 'net primary productivity') that was suggested in the fossil record. We then used a recently developed carbon cycle model called SCION to test our hypothesis numerically. When we analysed our model results we found that the initial increase in temperature from the Siberian Traps was preserved for five to six million years after the event because of the reduction in net primary productivity. It was only as plants re-established themselves and the organic carbon cycle restarted that Earth slowly started to ease out of the super greenhouse conditions. Maintaining a climate equilibrium It's always difficult to draw analogies between past climate change in the geological record and what we're experiencing today. That's because the extent of past changes is usually measured over tens to hundreds of thousands of years while at present day we are experiencing change over decades to centuries. A key implication of our work, however, is that life on Earth, while resilient, is unable to respond to massive changes on short time scales without drastic rewirings of the biotic landscape. In the case of the Permian–Triassic mass extinction, plants were unable to respond on as rapid a time scale as 1,000 to 10,000 years. This resulted in a large extinction event. Overall, our results underline how important tropical and subtropical plant biomes and environments are to maintaining a climate equilibrium. In turn, they show how the loss of these biomes can contribute to additional climate warming – and serve as a devastating climate tipping point. Zhen Xu was the lead author of the study, which was part of her PhD work. Andrew Merdith is a DECRA Fellow at the School of Earth Sciences, University of Adelaide. Benjamin J. W. Mills is a Professor of Earth System Evolution at the University of Leeds. Zhen Xu is a Research Fellow at the School of Earth and Environment, University of Leeds.
