Latest news with #Pliocene
Time of India
a day ago
- Science
- Time of India
CO2 spike hastens melting of West Antarctic ice sheet, lethal sea surge looms, shows study by Goa-based NCPOR
Panaji: A new study by the National Centre for Polar and Ocean Research (NCPOR), Goa, warns that a critical part of the west Antarctic ice sheet is already undergoing rapid and potentially irreversible melting. The west Antarctic ice sheet contains enough ice to raise global sea levels by over three to five metres. Once destabilised, the ice could rapidly disintegrate, discharging massive volumes into the Antarctic Ocean. The melting is driven not only by rising air temperatures but also by the intrusion of warm ocean waters beneath the ice sheet. The findings paint a concerning picture for global sea-level rise, with direct implications for coastal regions and low-lying areas, including in India. The research, published in the journal Nature Communications, focuses on a particularly vulnerable area known as the Amundsen Sea Embayment. This region is home to some of the world's fastest-melting glaciers, including the Thwaites 'doomsday' glacier. The study led by NCPOR has traced the origins of stability in the west Antarctic ice sheet to a critical climate transition that occurred 2.7-2.5 million years ago — a period marking the shift from the warm Pliocene to a cold Pleistocene climate. by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like They Were So Beautiful Before; Now Look At Them; Number 10 Will Shock You Reportingly Undo For climate scientists, the Pliocene period, 5.3-2.6 million years ago, is the best comparison with present-day climate conditions. The Pliocene period experienced 2-3°C higher temperatures, and atmospheric carbon dioxide levels were between 350 parts per million (ppm) and 450ppm, which are comparable to the early 21st century and 25-60% higher than pre-industrial values. The peer-reviewed study shows that the west Antarctic ice sheet remained remarkably stable for nearly 2.6 million years. Earlier climate models suggested that the west Antarctic ice sheet may have experienced frequent collapses during warmer interglacial periods of the Pleistocene era. The new evidence challenges that view. Instead, the findings suggest that once the ice sheet expanded around 2.7 million years ago, it remained stable even during the warmest intervals. The resilience that endured is now under threat. Present-day carbon dioxide levels have crossed 420ppm. According to the study's lead author, paleoclimatologist Waliur Rahaman, the earth is fast approaching the point of no return for ice sheet expansion and long-term stability. 'Present-day climate conditions are similar to those during the Pliocene period, suggesting we are approaching or may have already crossed a similar tipping point,' said Rahaman, a scientist at NCPOR. Rahaman said, 'Though the study does not pinpoint an exact timeline, it provides compelling evidence that we are dangerously close to crossing the threshold. The message is unequivocal: the window to prevent irreversible west Antarctic ice sheet collapse is rapidly approaching, underscoring the urgent need for immediate and decisive climate action.' Even if global temperatures were to return to pre-industrial levels in the future, scientists warn, the ice sheet may no longer recover to its original size. 'The current phase of rapid melting and mass loss is thus considered unprecedented in the last 2.7 million years,' Rahaman said. By providing a robust geological reference, NCPOR's research strengthens future climate model predictions and contributes to more accurate forecasting of sea-level rise. Stay updated with the latest local news from your city on Times of India (TOI). Check upcoming bank holidays , public holidays , and current gold rates and silver prices in your area.
Yahoo
02-06-2025
- Entertainment
- Yahoo
Megalodon Tooth Millions of Years Old Found in Florida (Video)
Call me crazy, uneducated, or what-have-you, but I thought the ancient Megalodon shark was just a myth. A fabled creature, akin to the kraken, trumpeted by Shark Week and other fear-mongering media, to entice viewers with shock and awe into their programming. Alas, I was wrong. Recently, a diver off the Gulf Coast of Florida made the find of a lifetime, discovering a six-inch tooth from the early Miocene to early Pliocene epochs, ranging from 23 to 3.6 million years ago. It was so rare, shark experts called it: 'Like winning the lottery. One chance in a million or more.' 'We were really close to the ground,' said Kristina Scott, who found the tooth while diving off Venice in Sarasota County with her boyfriend. 'I saw just the root of it, covered in barnacle. I knew the shape. And I pulled it out of the dirt, and started freaking out. I pulled his [her boyfriend's] arm. I was trying to yell with the regulator in my mouth. But yeah, we were just stoked.'When compared to other shark teeth, this megalodon fang makes modern sharks look like sardines. But how big, exactly, were these ancient behemoths. Well, there's only fossil records to go off, but scientists have some ideas. According to a Smithsonian report on the carcharocles megalodon: 'Carcharocles megalodon was once the most fearsome predator to reign the seas. This ancient shark lived roughly 23 to 3.6 million years ago in nearly every corner of the ocean. Roughly up to 3 times the length of a modern-day great white shark, it is the largest shark to have ever lived. It had a powerful bite with a jaw full of teeth as large as an adult human's hand. They likely could tear chunks of flesh from even the largest whales of the time. It should come as no surprise that upon discovery in the fossil record, the massive shark was named Carcharocles megalodon or 'big toothed glorious shark.'' As for the rarity (and potential price tag) of such a find from the diver in Florida – as in, could she cash in on it? – the newscasters could only fathom: 'From our understanding, this is, like, museum-quality stuff…it's a big deal.'Megalodon Tooth Millions of Years Old Found in Florida (Video) first appeared on Surfer on Jun 2, 2025
Miami Herald
05-05-2025
- Science
- Miami Herald
‘Strange' fossilized teeth found in Caribbean. It's a ‘giant' prehistoric species
A mystery has been building in the Caribbean. Decades ago, fossilized teeth were discovered in Cuba dating to about 18 million years ago. They were small but tapered, sharp and serrated. They were the teeth of an apex predator. Researchers didn't believe there was such an animal in the Caribbean, until they found another tooth in Puerto Rico, this time 29 million years old, according to an April 30 news release from the Florida Museum of Natural History. Still, the teeth alone weren't enough to identify the prehistoric species. Then, along a road in the Dominican Republic in 2023, paleontologists unearthed not only another tooth, but vertebrae to match, the museum said. They had an identity. It was a crocodile-like reptile 'built like a greyhound' and sometimes reaching 20 feet long — a sebecid. Not only did the Caribbean house these 'giant' predators after all, but the animals were living there millions of years after their extinction everywhere else, the museum said. Researchers described the findings and what it might mean in a study published April 30 in the peer-reviewed journal Proceedings of the Royal Society B. The cervical vertebrae and teeth were found in an embankment along the Juan Pablo II highway when roadcuts revealed sediment from the late Miocene and early Pliocene epochs, according to the study. 'Outcrops don't last too long, so you go there when you can. When they're cutting the road or a few months after that, you find the fossils. If you're looking in a few years, it will be gone,' Lázaro W. Viñola López, a former graduate student at the University of Florida and lead author on the study, said in the release. 'That emotion of finding the fossil and realizing what it is, it's indescribable,' he said. Sebecids belonged to a group of prehistoric crocodilians called Notosuchia, a group that was all but wiped out 66 million years ago, according to the museum. With dinosaurs out of the way, sebecids thrived in South America as the new apex predator, able to move quickly on land and use their teeth to rip apart their prey, the museum said. Sebecids likely wouldn't have been able to swim from mainland South America to the Caribbean islands, researchers said in the study, suggesting the landmasses were once connected by some kind of land bridge millions of years ago. There could have also been a chain of smaller islands, making the swimming distance more manageable, for the sebecids to survive in the Caribbean, the museum said. This idea is called the GAARlandia hypothesis and suggests these connections were present about 34 million years ago. 'You wouldn't have been able to predict this looking at the modern ecosystem,' Jonathan Bloch, curator of vertebrate paleontology at the Florida Museum of Natural History and co-author on the study, said in the release. 'The presence of a large predator is really different than we imagined before, and it's exciting to think about what might be discovered next in the Caribbean fossil record as we explore further back in time.' The new fossils were found in Sabana Grande De Boya in central Dominican Republic, an island nation in the eastern Caribbean. The research team includes Viñola López, Bloch, Jorge Velez-Juarbe, Philippe Münch, Juan N. Almonte Milan, Pierre-Olivier Antoine, Laurent Marivaux and Osvaldo Jimenez-Vasquez.
Zawya
10-04-2025
- Science
- Zawya
Saudi study uncovers ancient humid periods that shaped Arabia's climate over 8mln years
RIYADH — The Saudi Heritage Commission has unveiled new evidence of recurrent humid periods that shaped the Arabian Peninsula's climate over the past 8 million years, according to a scientific study published in Nature. The research, conducted under the Green Arabia Project, is based on one of the longest and most precisely dated cave records ever collected from central Arabia. The study analyzed 22 speleothems — mineral formations in caves — from seven cave systems in central Saudi Arabia. These deposits, some dating back to 7.44 million years ago, provide direct evidence of ancient episodes of increased rainfall and vegetation, contrasting sharply with the region's current hyperarid conditions. Key findings show that central Arabia experienced multiple phases of elevated water availability, especially during the late Miocene, early Pliocene, and middle Pleistocene. These wetter intervals would have supported rivers, lakes, and rich ecosystems, enabling the movement of water-dependent animals such as crocodiles, hippopotamuses, and elephants—species that once roamed Arabia but are now extinct in the region. The humid episodes also likely created corridors for early human and mammal dispersals between Africa and Eurasia, positioning Arabia as a key crossroads for biogeographic exchange. Fossil evidence from the late Miocene Baynunah Formation and middle Pleistocene Nefud Desert supports this theory. Researchers observed that these wet phases gradually became shorter and less intense over time, marking a trend toward increasing aridity. The transition coincides with global climate changes, including Northern Hemisphere glaciation and weakening monsoon systems. After the mid-Pleistocene transition around 700,000 years ago, evidence suggests only limited precipitation, often insufficient to sustain the lush environments of earlier epochs. Another significant discovery is the shift in the origin of rainfall. Isotopic analysis of ancient cave water trapped in speleothems shows a progressive decline in monsoon-derived moisture from the south, replaced increasingly by winter rainfall from the north. This change reflects a broader shift in global atmospheric circulation patterns. © Copyright 2022 The Saudi Gazette. All Rights Reserved. Provided by SyndiGate Media Inc. (
Gulf Insider
09-04-2025
- Science
- Gulf Insider
Saudi Study Uncovers Ancient Humid Periods That Shaped Arabia's Climate Over 8 Million Years
The Saudi Heritage Commission has unveiled new evidence of recurrent humid periods that shaped the Arabian Peninsula's climate over the past 8 million years, according to a scientific study published in Nature. The research, conducted under the Green Arabia Project, is based on one of the longest and most precisely dated cave records ever collected from central Arabia. The study analyzed 22 speleothems — mineral formations in caves — from seven cave systems in central Saudi Arabia. These deposits, some dating back to 7.44 million years ago, provide direct evidence of ancient episodes of increased rainfall and vegetation, contrasting sharply with the region's current hyperarid conditions. Key findings show that central Arabia experienced multiple phases of elevated water availability, especially during the late Miocene, early Pliocene, and middle Pleistocene. These wetter intervals would have supported rivers, lakes, and rich ecosystems, enabling the movement of water-dependent animals such as crocodiles, hippopotamuses, and elephants—species that once roamed Arabia but are now extinct in the region. The humid episodes also likely created corridors for early human and mammal dispersals between Africa and Eurasia, positioning Arabia as a key crossroads for biogeographic exchange. Fossil evidence from the late Miocene Baynunah Formation and middle Pleistocene Nefud Desert supports this theory. Researchers observed that these wet phases gradually became shorter and less intense over time, marking a trend toward increasing aridity. The transition coincides with global climate changes, including Northern Hemisphere glaciation and weakening monsoon systems. After the mid-Pleistocene transition around 700,000 years ago, evidence suggests only limited precipitation, often insufficient to sustain the lush environments of earlier epochs. Another significant discovery is the shift in the origin of rainfall. Isotopic analysis of ancient cave water trapped in speleothems shows a progressive decline in monsoon-derived moisture from the south, replaced increasingly by winter rainfall from the north. This change reflects a broader shift in global atmospheric circulation patterns.
