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Categories: Paleontology: Climate, Paleontology: Dinosaurs
Published North Atlantic Oscillation contributes to 'cold blob' in Atlantic Ocean
(via sciencedaily.com) Original source A patch of ocean in the North Atlantic is stubbornly cooling while much of the planet warms. This anomaly -- dubbed the 'cold blob' -- has been linked to changes in ocean circulation, but a new study found changes in large-scale atmospheric patterns may play an equally important role, according to an international research team.
Published Insolation affected ice age climate dynamics
(via sciencedaily.com) Original source In past ice ages, the intensity of summer insolation affected the emergence of warm and cold periods and played an important role in triggering abrupt climate changes, a study by climate researchers, geoscientists, and environmental physicists suggests. Using stalagmites in the European Alps, they were able to demonstrate that warm phases appeared primarily when the summer insolation reached maxima in the Northern Hemisphere.
Published New archosaur species shows that precursor of dinosaurs and pterosaurs was armored
(via sciencedaily.com) Original source Researchers have described a new species of armored reptile that lived near the time of the first appearance of dinosaurs. With bony plates on its backbone, this archosaur fossil reveals that armor was a boomerang trait in the story of dinosaur and pterosaur evolution: the group's ancestors were armored, but this characteristic was lost and then independently re-evolved multiple times later among specialized dinosaurs like ankylosaurs, stegosaurs, and others.
Published Greenland melted recently: High risk of sea level rise today
(via sciencedaily.com) Original source A large portion of Greenland was an ice-free tundra landscape -- perhaps covered by trees and roaming woolly mammoths -- in the recent geologic past (about 416,000 years ago), a new study shows. The results help overturn a previous view that much of the Greenland ice sheet persisted for most of the last two and a half million years. Instead, moderate warming, from 424,000 to 374,000 years ago, led to dramatic melting. At that time, the melting of Greenland caused at least five feet of sea level rise, despite atmospheric levels of heat-trapping carbon dioxide being far lower than today (280 vs. 420 ppm). This indicates that the ice sheet on Greenland may be more sensitive to human-caused climate change than previously understood -- and will be vulnerable to irreversible, rapid melting in coming centuries.
Published Unusual fossil shows rare evidence of a mammal attacking a dinosaur
(via sciencedaily.com) Original source Scientists have described an unusual fossil from around 125 million years ago in China that shows a dramatic moment in time when a carnivorous mammal attacked a larger plant-eating dinosaur. The two animals are locked in mortal combat, and it's among the first evidence to show actual predatory behavior by a mammal on a dinosaur. The fossil's presence challenges the view that dinosaurs had few threats from their mammal contemporaries during the Cretaceous, when dinosaurs were the dominant animals.
Published Crawford Lake, Canada, chosen as the primary marker to identify the start of the Anthropocene epoch
(via sciencedaily.com) Original source An international team of researchers has chosen the location which best represents the beginnings of what could be a new geological epoch, the Anthropocene. The Anthropocene Working Group have put forward Crawford Lake, in Canada, as a Global Boundary Stratotype Section and Point (GSSP) for the Anthropocene. A GSSP is an internationally agreed-upon reference point to show the start of a new geological period or epoch in layers of rock that have built up through the ages.
Published Global cooling caused diversity of species in orchids, confirms study
(via sciencedaily.com) Original source Research shows global cooling of the climate 10 million years ago led to an explosion of diversity in terrestrial orchids.
Published Why there are no kangaroos in Bali (and no tigers in Australia)
(via sciencedaily.com) Original source Researchers are using a new model to clarify why millions of years ago more animal species from Asia made the leap to the Australian continent than vice versa. The climate in which the species evolved played an important role.
Published Shrinking Arctic glaciers are unearthing a new source of methane
(via sciencedaily.com) Original source As the Arctic warms, shrinking glaciers are exposing bubbling groundwater springs which could provide an underestimated source of the potent greenhouse gas methane, finds new research.
Published Fossils reveal how ancient birds molted their feathers -- which could help explain why ancestors of modern birds survived when all the other dinosaurs died
(via sciencedaily.com) Original source Birds are the only group of dinosaurs that survived the asteroid-induced mass extinction 66 million years ago. But not all the birds alive at the time made it. Why the ancestors of modern birds lived while so many of their relatives died has been a mystery that paleontologists have been trying to solve for decades. Two new studies point to one possible factor: the differences between how modern birds and their ancient cousins molt their feathers.
Published New study reveals abrupt shift in tropical Pacific climate during Little Ice Age
(via sciencedaily.com) Original source An El Niño event has officially begun. The climate phenomenon, which originates in the tropical Pacific and occurs in intervals of a few years will shape weather across the planet for the next year or more and give rise to various climatic extremes. El Niño-like conditions can also occur on longer time scales of decades or centuries. This has been shown to have occurred in the recent past.
Published Research reveals sources of CO2 from Aleutian-Alaska Arc volcanoes
(via sciencedaily.com) Original source Scientists have wondered what happens to the organic and inorganic carbon that Earth's Pacific Plate carries with it as it slides into the planet's interior along the volcano-studded Ring of Fire. A new study suggests a notable amount of such subducted carbon returns to the atmosphere rather than traveling deep into Earth's mantle.
Published Climate change will increase impacts of volcanic eruptions
(via sciencedaily.com) Original source Volcanic disasters have been studied since Pompeii was buried in 79 A.D., leading the public to believe that scientists already know why, where, when and how long volcanoes will erupt. But a volcanologist said these fundamental questions remain a mystery.
Published There may be good news about the oceans in a globally warmed world
(via sciencedaily.com) Original source An analysis of oxygen levels in Earth's oceans may provide some rare, good news about the health of the seas in a future, globally warmed world. A study analyzing ocean sediment shows that ocean oxygen levels in a key area were higher during the Miocene warm period, some 16 million years ago when the Earth's temperature was hotter than it is today.
Published Newly discovered Jurassic fossils in Texas
(via sciencedaily.com) Original source Scientists have filled a major gap in the state's fossil record -- describing the first known Jurassic vertebrate fossils in Texas. The weathered bone fragments are from the limbs and backbone of a plesiosaur, an extinct marine reptile.
Published Humans' ancestors survived the asteroid impact that killed the dinosaurs
(via sciencedaily.com) Original source A Cretaceous origin for placental mammals, the group that includes humans, dogs and bats, has been revealed by in-depth analysis of the fossil record, showing they co-existed with dinosaurs for a short time before the dinosaurs went extinct.
Published AI reveals hidden traits about our planet's flora to help save species
(via sciencedaily.com) Original source Machine learning can help extract important information from the huge numbers of plant specimens stored in herbaria, say scientists.
Published New dinosaur discovered: Ankylosaurs may have been far more diverse than originally thought
(via sciencedaily.com) Original source First armoured dinosaur to be described from the Isle of Wight in 142 years, shows Ankylosaurs may have been far more diverse than originally thought
Published Massive underwater plateau near Solomon Islands is younger and its eruption was more protracted than previously thought
(via sciencedaily.com) Original source The Ontong Java Plateau, a volcanically-formed underwater plateau located in the Pacific Ocean north of the Solomon Islands, is younger and its eruption was more protracted than previously thought, new research suggests.
Published Climate change likely led to violence in early Andean populations
(via sciencedaily.com) Original source Climate change in current times has created problems for humans such as wildfires and reduced growing seasons for staple crops, spilling over into economic effects. Many researchers predict, and have observed in published literature, an increase in interpersonal violence and homicides when temperatures increase. Violence during climatic change has evidence in history, anthropology researchers say.