The pace of global warming today is forcing scientists to search the ancient rock record for any precedent that resembles the changes now unfolding across the modern Earth. Most past climate swings occurred gradually over vast spans of time. A few, however, were abrupt and severe enough to push the planet into a different climate state in a geological instant. A newly published study reveals that one of these events was far more violent and far more instructive for the present world than previously understood. It happened 290 million years ago during the Late Paleozoic Ice Age, and it began with a pattern that is now visible again. Glaciers began to retreat across multiple continents while atmospheric carbon increased. Then one of the planet’s main natural stabilizing systems collapsed. Once that happened, the warming accelerated beyond anything that had occurred for millions of years. This event is now known as the Artinskian Warming Event, and the new research shows that it was amplified by the failure of low latitude silicate weathering, a process that ordinarily removes carbon dioxide from the atmosphere and slows climate change. When this process weakened across the tropics, the Earth’s climate shifted rapidly into a greenhouse state. The scale and speed of the transition were unprecedented during the entire ice age. The physics and chemistry behind that collapse have precise modern parallels, which raises new concerns about where current warming may be heading.
The Late Paleozoic Ice Age was one of the longest glacial intervals in Earth’s history. It lasted tens of millions of years and produced widespread ice cover across the supercontinent Gondwana. During the height of this ice age, thick ice sheets extended across South America, Africa, India, Australia, and Antarctica. The ice retreated and advanced over time, but the overall climate remained within a stable range until the early Permian. The new study focuses on geochemical changes preserved in carbonate rocks from the Naqing section of South China. The site was located near the equator during the Permian, which makes it an ideal location for tracking low latitude climate feedbacks. The research team analyzed carbon isotopes, organic carbon, mercury concentrations, and chemical weathering indices to reconstruct the events that unfolded during the Artinskian Warming Event.
The first signs of disruption appear in the late Sakmarian stage, when carbon isotope values began to fall. This signals a disturbance in the global carbon cycle. At the same time, chemical index of alteration values rose, showing that weathering intensity on land was increasing. Warmer and more humid conditions intensify weathering, so the data indicate that climate warming was already underway. The situation accelerated as the Artinskian began. Carbon isotopes plunged sharply, organic carbon values shifted, mercury concentrations spiked, and weathering indices reached extremely high values. The combination points to widespread volcanic activity that released large amounts of carbon dioxide into the atmosphere. The Tarim province, the Panjal Traps, and the Choiyoi arc were all active during this interval, and each produced extensive volcanic emissions. Mercury is frequently used as an indicator of volcanic input, and the samples from Naqing show the strongest mercury enrichment during the peak of the warming event. This confirms that volcanism played a major role in initiating the climate shift.
What makes this study alarming is not simply the identification of volcanic emissions. Earth has experienced large igneous province eruptions many times. What matters is what happened after the warming began. Silicate weathering is one of the planet’s main regulators of long term climate. When silicate minerals break down, they consume carbon dioxide and deliver ions to the ocean that eventually become carbonate rocks. This process draws down atmospheric carbon and counters volcanic degassing. Ordinarily, warming accelerates chemical weathering, which increases carbon dioxide removal. It is one of the planet’s natural braking systems. During the Artinskian, however, that braking system failed.
The authors used the Celine Model, a quantitative weathering estimate, to calculate how much carbon dioxide was being consumed by tropical mafic rocks during the early Permian. These rocks are highly effective at pulling carbon dioxide from the atmosphere because they weather rapidly and contain minerals that react strongly with rainwater. The model shows that the area of low latitude mafic rock exposed at the surface began to shrink at the same time the atmosphere was receiving new carbon from volcanic eruptions. As sea level rose during deglaciation, many of these rocks became submerged. As continents drifted northward, tropical belts shifted, changing the distribution of weatherable terrain. The combined effect was a sharp decline in the total weathering flux despite rising temperatures. In other words, the system that should have removed excess carbon from the atmosphere and counterbalanced the warming lost its effectiveness at the worst possible moment.
Once this occurred, the warming intensified. The ice sheets retreated across multiple continents. The report illustrates the timing of ice loss in South America, Africa, India, Saudi Arabia, Antarctica, and Australia. In region after region, glacial deposits disappear during the Artinskian. Sea level rose as meltwater poured into the oceans. Tropical forests collapsed as the climate shifted toward arid conditions. The fossil record shows that moisture loving plants declined sharply while drought tolerant, xeromorphic species expanded. Coal bearing deposits gave way to red beds across northern Pangea, recording the spread of dry landscapes. Marine organisms were also hit hard. Fusuline foraminifera reached their peak before the warming began, then declined rapidly. The data indicate a major ecological shift linked to the climate transformation.
The key finding is that the warming was not steady. It surged when the atmospheric carbon sink weakened. The pattern is visible in the geochemical record. Carbon isotopes do not decline gradually. They plunge. Mercury peaks sharply. Weathering indices spike, then fall. The decline marks the moment when warm temperatures were no longer accompanied by strong weathering. Instead of stabilizing the climate, the land surface stopped counteracting carbon buildup. This is the point where the Artinskian Warming Event became one of the most intense deglaciation phases of the entire ice age.
Current global conditions share several features with the early stages of the Artinskian pattern. Glaciers in Greenland, Antarctica, the Himalayas, the Andes, and Alaska are retreating faster than predicted by earlier climate models. Atmospheric carbon dioxide levels are rising at a rate unmatched in the geological record outside of major extinction intervals. Forest dieback, permafrost thaw, and shifting rainfall patterns are altering the efficiency of several major carbon sinks. Chemical weathering is sensitive to temperature, rainfall, vegetation cover, and the exposure of fresh rock. Modern land use is reducing forest cover, which increases erosion but does not always increase weathering in a way that draws down carbon. Soil loss can strip landscapes of the materials needed to sustain long term silicate reactions. In tropical regions, deforestation exposes land to intense rainfall that can wash away fine material before it has time to chemically react. In high latitudes, permafrost thaw exposes new surfaces but simultaneously releases carbon that overwhelms any potential increase in weathering over short timescales. The relationship between climate change and weathering is complex, and the new research highlights that warming alone does not guarantee stronger carbon sinks.
The most important parallel concerns the potential failure of major stabilizing mechanisms. The Artinskian Warming Event demonstrates that once a natural carbon sink begins to weaken, the climate does not enter a slow and manageable transition. It shifts into a different state. The geological record shows that this shift can occur even without a singular catastrophic trigger. The volcanic eruptions that began the event were significant, but the abrupt intensification occurred only when weathering flux declined. The loss of stabilizing power amplified the warming far beyond what eruptive emissions alone would have produced.
Modern Earth relies heavily on the ability of oceans, soils, and vegetation to absorb carbon dioxide. These systems function as the primary counterweight to the emissions entering the atmosphere. As the planet warms, these systems are becoming less predictable. The ocean is absorbing heat that reduces mixing between surface and deep layers. Reduced mixing diminishes the ocean’s ability to transport carbon into long term storage. Forest stress reduces photosynthesis rates. Drought alters soil chemistry. The new study provides a direct ancient example of what happens when natural sinks weaken during a period of rapid warming.
Geochemical evidence from the Naqing section shows that once the flux of tropical mafic weathering declined, the atmosphere accumulated carbon dioxide more rapidly, the carbon isotopes reflected a major shift in the carbon cycle, and continental ice retreated across the globe. The rate of change accelerated. Because weathering is a slow geological process, it did not rebound quickly enough to counteract the new conditions. The system passed a threshold where the climate momentum carried the warming forward until a greenhouse state was fully established. Nothing in the record suggests a gradual cooling back to the previous equilibrium. The ice age ended permanently.
The Artinskian pattern is not identical to modern climate change, but the core mechanism is relevant. When atmospheric carbon sources exceed the strength of natural sinks, and when those sinks weaken rather than intensify, the rate of warming increases sharply. Geological data provide the only long term record of how the Earth system behaves under such conditions. In this case, the behavior was rapid, global, and transformative. The loss of the weathering sink was the inflection point.
This new research demonstrates that the planet has already experienced an event where warming accelerated unexpectedly because stabilizing processes broke down. The event produced widespread environmental change including ice loss, sea level rise, continental aridification, and biological decline. The parallels do not imply inevitability, but they show that once certain thresholds are crossed, the Earth system responds in ways that are abrupt rather than steady. The Artinskian record is clear. When carbon sinks weaken during rapid warming, the climate enters a new trajectory that does not reverse on human or even civilizational timescales. The study provides a factual case where a single feedback failure amplified warming across the planet and brought a long standing ice age to a close.
This research offers one of the clearest geological examples of how quickly a cold Earth can transition into a hot Earth when the processes that normally stabilize the climate lose their effectiveness. It stands as a detailed record of a system that moved from stable glacial conditions into a greenhouse world through a series of interacting feedbacks. The pattern began with warming, accelerated when the carbon sink weakened, and culminated in the permanent retreat of global ice. The timing and sequence are preserved in geochemical markers that show a rapid transformation consistent across multiple continents. The data illustrate a climate system capable of abrupt shifts when underlying controls fail.
The Artinskian Warming Event reveals that the Earth system can cross a threshold where warming is reinforced by the very processes that should slow it. Once that threshold was crossed in the Permian, the change was rapid and widespread. The conditions that produced it are now better understood, and the new analysis shows a mechanism that is relevant for understanding the direction of modern climate change.
Source:
Sun, S., Chen, A., Ogg, J.G., et al. An abrupt drop in weathering flux amplified the Artinskian Warming Event during the Late Paleozoic Ice Age. Communications Earth & Environment, 2026.
https://doi.org/10.1038/s43247-026-03288-3
