Articles tagged with Paleoclimatology
A University of Michigan study found that El Niño events have become nearly 40% stronger in the last 40 years than in the pre-industrial era. The study, which examined modern and ancient corals in the Galápagos Islands, found that El Niño events in the last four decades were stronger than any in the 1,000 years prior to about 1850.
Researchers analyzed ice cores from the Andes in Peru, revealing a 2,000-year-old record of global methane evolution. The findings support the hypothesis that tropical methane emissions dominated the Earth during the pre-industrial period, with human-driven agricultural and industrial emissions contributing to increases in later periods.
Scientists propose a colossal cliff across ancient North America may have exposed Grand Canyon's oldest rocks nearly a billion years before it was carved by the Colorado River. The study suggests the 'great escarpment' of steep rocky cliffs formed when the supercontinent Rodinia broke apart 800 million years ago.
A weakening Atlantic Ocean current system, known as the AMOC, could exacerbate global warming by distributing heat unevenly around the planet. During periods with a strong AMOC, the global ocean loses heat, while weak AMOC periods lead to a net increase in heat stored by the ocean.
Researchers studied ancient penguin fossils on Seymour Island to understand past climate change. The analysis of chemical elements across the bones revealed differences in elemental composition between warm and cool periods.
New research suggests that Agulhas Leakage does not directly regulate the AMOC through salt transport, challenging a long-held textbook concept. Instead, changes in ocean temperature and thermocline structure play a crucial role in shaping the climate system.
Scientists used chemical clues in microscopic fossils to find evidence that ocean acidification caused one of the largest extinction events in planktic foraminifera history. The study suggests that volcanic eruptions and rising CO2 levels led to a decrease in shell-building ability, ultimately contributing to the extinction.
A new study from Stockholm University found that the most severe droughts in the ancient Eastern Mediterranean arose when multiple natural climate cycles coincided. This helped explain why the drought associated with the Late Bronze Age collapse were so severe, pushing societies beyond a critical hydroclimatic threshold.
A new study found that massive wildfires occurred in fern-dominated landscapes across Northwest Europe during the Triassic period, lasting from 40,000 to 300,000 years. The research team used a novel technique to detect dark-colored microfossils, indicating prolonged and intense wildfires.
Researchers discovered natural sulfur and carbon emissions from metamorphic rocks contribute to cooling spikes, while carbon remains in the atmosphere for centuries, influencing ancient ecosystem reorganizations. These findings shed new light on mass-extinction events, such as the Ordovician, Devonian, Permian, and Triassic Periods.
A study reveals that natural cooling of coral reefs varies with large-scale climate oscillations, including ENSO and IOD. Coral skeletons provide a record of past subsurface temperatures and biological responses to heat stress, highlighting the dynamic relationship between climate refuges and their effectiveness in protecting corals fr...
Researchers found evidence that the Aleutian Islands' subduction beneath the North American Plate occurred at least 56 million years ago, significantly earlier than previously thought. This discovery has implications for understanding tectonic and climatic processes that shaped the Earth's history.
Researchers found that carbon from land was eroded and transported into the ocean, locking some carbon away for long periods. This process may have acted as a stabilising climate feedback, helping to gradually reduce atmospheric carbon levels over thousands to tens of thousands of years.
Research reveals volcanic eruptions shape monsoon dynamics on centennial timescales, cooling the Northern Hemisphere and reducing cross-equatorial moisture transport. This process, combined with a mega-ENSO-like sea surface temperature anomaly pattern, decreases rainfall across Asian, North African, and North American monsoon regions.
A new study reveals that North America experienced stronger enrichment of oxygen isotopes in the north during the last deglaciation, while the south showed a muted response. The researchers used climate simulations to explain this difference, attributing it to changes in atmospheric circulation and moisture sources.
The study of exceptionally preserved fossils from a 62.2-million-year-old site in Egypt reveals that modern marine fish communities were already established approximately 4 million years after the dinosaur extinction. The Qreiya 3 Lagerstätte, an offshore marine ecosystem from the Danian Age, has yielded hundreds of fossil fishes, incl...
Researchers have developed a way to improve records of past high-latitude ocean change by analyzing tiny plankton shells called foraminifera. The new calibration tool extends the key temperature tool into colder seas, enabling more accurate reconstructions of climate and ocean circulation changes.
Scientists have discovered a previously unknown mechanism that transfers heat into the deep ocean, even when surface water temperatures remain stable. The study reveals an abrupt 5°C warming in intermediate waters at 800 meters depth over the past 11,000 years, linked to changes in Southern Hemisphere ocean-atmosphere circulation.
A new study reveals that the Antarctic ice sheet responded sharply to climate change following a major shift in Earth's ice age cycles. The simulation found that below a critical atmospheric CO2 level, the amplitude of Antarctic ice variations increases in response to changes in temperatures.
The study shows a significant 5°C warming of intermediate waters at 800m depth in the equatorial Atlantic over the last 11,000 years. This warming is not mirrored by changes in tropical sea surface temperatures, indicating an extratropical origin.
A new study reveals Antarctica's sea ice collapse is driven by a triple whammy of climate chaos, resulting in record-breaking lows. The Southern Ocean's transformation led to the loss of vast areas of ice equivalent to Greenland, destabilizing global ocean currents and accelerating global warming.
The upper-level subtropical westerly jet over East Asia shows a weakened long-term trend under orbital forcing but strengthens under greenhouse gas forcing. This study challenges the simple assumption that warming means weakening and suggests the jet could become stronger under future global warming.
The East Asian Subtropical Westerly Jet (EASWJ) and East Asian Summer Monsoon (EASM) relationship shows stable anti-phase changes across three climate periods. A significant mode shift is identified in the second MV-EOF mode, with varying relationships between EASWJ displacement and EASM intensity.
Researchers used climate simulations to study the formation of the Antarctic Circumpolar Current around 34 million years ago. The findings show that a reorganisation of global ocean circulation took place during this time, which had significant effects on carbon uptake and the onset of the Cenozoic Ice Age.
Research reveals increased interannual temperature variability over China, with greater summer variability during the Last Interglacial and stronger winter variability during the Last Glacial Maximum. This study provides a critical long-term perspective for understanding future changes in extreme temperature events.
Researchers analyzed 11,000-year-old bowhead whale fossils to reveal the devastating impact of commercial whaling on the species' genetics. The study found that genetic diversity will continue to decline, severely impacting the species' resilience to climate change.
A new 'rock clock' has been developed to date major climate events from the Cambrian Period, allowing precise constraints on the timing of environmental changes. This advancement enables the determination of the timing and duration of the DrumIan Carbon isotope Excursion (DICE), a major global climate disturbance.
Scientists extracted thousands of years' worth of air pollution from a 9.5-meter ice core, recording medieval mining, fires, and volcanoes. However, global warming is destroying this frozen archive, and researchers warn that it's a race against time to capture critical climate information.
A recent study found that tropical algae were largely unaffected by periods of global warming up to 1.5 degrees Celsius in the distant past. This resilience provides valuable insights into the potential consequences of climate change and supports the goal of limiting global warming to 1.5 degrees.
A new study from Brown University finds that temperatures in parts of the tropics may increase by up to 4.8 degrees C due to rising CO2 levels. This is significantly higher than previously predicted, highlighting the importance of studying regional climate mechanisms.
Researchers found a surprising correlation between West Antarctic Ice Sheet retreat and marine algae growth over the past 500,000 years. The study suggests that global warming may lead to reduced CO2 uptake if the ice sheet continues to shrink.
A new study reveals a surprising link between West Antarctic Ice Sheet retreat and algae growth over the past 500,000 years. Iron-rich sediments from icebergs stimulate algae growth, but in a less bioavailable form than previously assumed.
Researchers found that animals living on convoluted coastlines were more likely to go extinct than those living on north-south orientated coastlines. This study provides new insight into patterns of biodiversity distribution throughout Earth history and highlights the importance of coastline geometry for survival during climate change.
Researchers used 'proxies' from the geological record to show that intense rainfall events were less regular during the Paleogene Period, which saw extreme warming. This challenges common assumptions about how wet places become wetter and drier with climate change.
Researchers used clumped-isotope palaeothermometry to reconstruct large temperature fluctuations at depths of up to 4,000 meters in the Southern Ocean. These fluctuations occurred simultaneously with changes in oxygen isotopes and Earth's orbital eccentricity, suggesting a climatic forcing.
Researchers discovered metabolites in fossilized bones of animals that lived 1.3 to 3 million years ago, providing insights into their health, diets, and environments. The findings revealed warmer and wetter conditions compared to today.
Researchers found that coral reefs governed the pace of climate recovery by tuning the planet's carbon and climate cycles. The study suggests that reefs played a crucial role in stabilizing climate, but modern reef systems are declining due to warming and ocean acidification.
A study suggests that prolonged droughts lasting over 85 years contributed to the decline of the Indus Valley Civilization. The civilization, which existed around 5,000-3,500 years ago, was characterized by advanced cities and sophisticated water management systems.
A calcite deposit in a southern Nevada cave has provided new insight into the region's hydroclimate, revealing significant shifts in temperature and rainfall over the last 580,000 years. The analysis suggests that temperature, availability of water, and vegetation are tightly coupled, with changes in one area impacting others.
Researchers have discovered that sudden shifts in the Southern Westerly Winds 15,000 years ago triggered a massive growth of ancient bogs across the Southern Hemisphere. The study found that the shifting winds created an ideal climate for the swamps to form, and now believe they play a crucial role in regulating carbon stores in peatland.
Researchers analyzed sediment cores from three sites in the Arctic, finding that year-round ice coverage corresponded with less cosmic dust. This study suggests that tracking cosmic dust can help predict changes to sea ice coverage and understand warming trends.
A UAlbany researcher is leading a $1.2 million NSF project to integrate climate records from stalagmites, corals, lake sediments, and tree rings to understand past changes in monsoon rainfall patterns. The study aims to improve decadal predictions and risk management for societies vulnerable to climate change.
Researchers have discovered the oldest directly dated ice and air on the planet, providing an unprecedented view of Earth's past climate. The 6-million-year-old ice cores reveal a gradual cooling trend of about 12 degrees Celsius over the last 6 million years.
A new study published in Science reveals that large fluctuations in global sea level occurred throughout the last ice age, rather than just at its end. This finding represents a significant shift in researchers' understanding of past climate history and challenges conventional wisdom on the middle Pleistocene transition.
The study reveals that the Patagonian ice sheet underwent periods of expansion and contraction, contrary to earlier assumptions. The driving force for long-term fluctuations was found to be changes in summer seasons and solar radiation, known as integrated summer energy.
A study has found that high-latitude phytoplankton communities responded to a pre-PETM warming event, highlighting the importance of examining background intervals in determining ecosystem change. The results suggest even small environmental changes can have dramatic impacts on marine ecosystems.
A new study suggests that the Earth's carbon cycle can overcorrect and plunge the planet into an ice age if greenhouse gas emissions continue to rise. The researchers found that in a warmer world with enhanced algae growth, the oceans lose oxygen, leading to a feedback loop that consumes more carbon.
Researchers in China have dated dinosaur eggs from the Qinglongshan site to be around 85 million years old, shedding light on the Late Cretaceous climate. The new dating method, called atomic clock for fossils, allows for precise measurement of uranium and lead atoms in eggshell samples.
A new study by the University of Gothenburg suggests that thawing permafrost played a significant role in raising carbon dioxide levels after the last ice age. Researchers estimate that this carbon exchange may have accounted for almost half of the rising CO2 levels.
A new method reconstructs carbon dioxide levels and photosynthesis from fossilized tooth enamel, shedding light on the climate of the Mesozoic era. The analysis found that atmospheric CO2 levels were four times higher in the late Jurassic period and three times higher in the late Cretaceous period than they are today.
Scientists have uncovered the remains of a vast animal community that lived in the European Arctic 75,000 years ago. The bones represent the oldest example of an animal community in the region during this warmer period of the ice age, providing valuable insights into how wildlife responded to dramatic climate shifts.
A large region of unusually hot rock deep beneath the Appalachian Mountains in the United States could be linked to Greenland and North America splitting apart 80 million years ago. The 'mantle wave' theory suggests that hot, dense rock slowly peels away from the base of tectonic plates after continents break apart.
Researchers at Göttingen University developed a method to reconstruct the early Earth's atmosphere using fossilized micrometeorites. The study found that intact micrometeorites can preserve reliable traces of oxygen isotopes over millions of years.
A 40-meter long ice core from Mont Blanc's Dôme du Goûter holds clues to 12,000 years of human and environmental history. The record provides insights into Europe's past climate, including a temperature difference of about 3 degrees Celsius between the last Ice Age and the current Holocene Epoch.
Researchers found that thick ice cover suppressed volcanic eruptions, but as glacial ice melts, pressure builds and magma is released, leading to more frequent and explosive eruptions. This phenomenon could occur worldwide, including Antarctica, and may have global climate impacts, including long-term warming.
Researchers used daily high-resolution images to create 3D elevation models of three glaciers: La Perouse Glacier in Alaska, Viedma Glacier in Argentina, and Skamri Glacier in Central Asia. The analysis revealed consistent thinning in the Viedma and La Perouse Glaciers but a small net gain of ice in the Skamri Glacier.
Researchers found five periods of decreased ocean oxygen concentrations coinciding with increased carbon dioxide levels 300 million years ago. This discovery highlights human-driven carbon dioxide emissions as a significant threat to marine biodiversity.
A study by Florida Atlantic University reveals that climate shifts starting around 500 A.D. led to shorter lives and faster growth in bald cypress trees, which may have made them more vulnerable to stress. The research provides a powerful lens into how widespread environmental changes can be.
The Global Declaration of Commitment for Scientific Ocean Drilling aims to promote global cooperation and collaboration in ocean science. The declaration sets out core principles for transparent access to data and samples, inclusive participation, environmental responsibility, and alignment with the UN SDGs.
Researchers uncover valuable insights into past climate scenarios and marine ecosystems through ancient sediment cores. The study highlights the need for more data to improve future climate models and transform our understanding of Earth's complex life systems.