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Categories: Geoscience: Volcanoes, Paleontology: Climate

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How is the weather changing as a consequence of global warming? Climate archives provide valuable glimpses into past climate changes, especially into the processes that drive our planet from one climate setting to the next. For humans and ecosystems, however, time spans of just weeks to years, which are the scope of weather events, are often most important. Using an newly developed and tested analytical method these two aspects have now been merged, and the impacts of the most recent global warming on seasonal temperature fluctuations have been described.

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Two-million-year-old DNA has been identified -- opening a 'game-changing' new chapter in the history of evolution. Microscopic fragments of environmental DNA were found in Ice Age sediment in northern Greenland. Using cutting-edge technology, researchers discovered the fragments are one million years older than the previous record for DNA sampled from a Siberian mammoth bone. The ancient DNA has been used to map a two-million-year-old ecosystem which weathered extreme climate change.

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A chance find of an unstudied Antarctic sediment core has led researchers to flip our understanding of how often ice ages occurred in Antarctica.

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The Southern Hemisphere is stormier than the Northern -- but no one knew why. A new study lays out the first concrete explanation for this phenomenon. Researchers found two major culprits: ocean circulation and the large mountain ranges in the Northern Hemisphere.

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Major ice streams can shut down, shifting rapid ice transport to other parts of the ice sheet, within a few thousand years. This was determined in reconstructions of two ice streams, based on ice-penetrating radar scans of the Greenland ice sheet.

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Years of research show that climate change signals are amplified in the Arctic, and that sea ice in this region is sensitive to increases in Arctic warming. Sea ice greatly modifies the exchanges of heat, momentum and mass between the atmosphere and the ocean. So, the timings of the sea ice melt and freeze onsets, as well as the length of the melt and freeze seasons, play a key role in the 'heat budget' of the atmosphere-ice-ocean system.

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A new analysis of more than 20,000 trees on five continents shows that old-growth trees are more drought tolerant than younger trees in the forest canopy and may be better able to withstand future climate extremes. The findings highlight the importance of preserving the world's remaining old-growth forests, which are biodiversity strongholds that store vast amounts of planet-warming carbon, according to forest ecologists.

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Paleontologists say environmental DNA is not always helpful in identifying when animals like mammoths went extinct because genetic material found in sediment could have come from animals that died thousands of years earlier.

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The 1930s Dust Bowl affected heat extremes across much of North America and as far away as Europe and East Asia, according to new research. The study found that the extreme heating of the Great Plains triggered motions of air around the Northern Hemisphere in ways that suppressed cloud formation in some regions and contributed to record heat thousands of miles away.

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A new article discusses vital methodological issues for humanities-based historical inquiry and argues that the challenges of the Anthropocene demand interdisciplinary research informed by a variety of historical narratives.

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Have humans wreaked too much havoc on marine life to halt damage? A new analysis challenges the idea that ocean ecosystems have barely changed over millions of years, pointing scientists down a new path on conservation efforts and policy.

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A new study compiles data on more than 3,000 species to show how climate and geologic changes across Asia over the last 66 million years have shaped the evolution of the continent's mammals.

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Volcanic eruptions are dangerous and difficult to predict. A team has found that the ratio of atoms in specific gases released from volcanic fumaroles (gaps in the Earth's surface) can provide an indicator of what is happening to the magma deep below -- similar to taking a blood test to check your health. This can indicate when things might be 'heating up.' Specifically, changes in the ratio of argon-40 and helium-3 can indicate how frothy the magma is, which signals the risk of different types of eruption. Understanding which ratios of which gases indicate a certain type of magma activity is a big step. Next, the team hopes to develop portable equipment which can provide on-site, real-time measurements for a 24/7 volcanic activity monitoring and early warning system.

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Using images captured by satellites, researchers have confirmed that the January 2022 eruption of the Hunga Tonga-Hunga Ha'apai volcano produced the highest-ever recorded plume. The colossal eruption is also the first to have been directly observed to have broken through to the mesosphere layer of the atmosphere.

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A chemical analysis of sediment cores from the North Pacific Ocean show a consistent pairing of volcanic ash and hypoxia, a low ocean oxygen interval spanning thousands of years, during times of rapid climate warming at the end of the last ice age, new research shows.

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Magma beneath long-dormant Mount Edgecumbe volcano in Southeast Alaska has been moving upward through Earth's crust, according to research the Alaska Volcano Observatory rapidly produced using a new method.

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The Plinian eruption of Mount Vesuvius around 4,000 years ago -- 2,000 years before the one that buried the Roman city of Pompeii -- left a remarkably intact glimpse into Early Bronze Age village life in the Campania region of Southern Italy. The village offers a rare glimpse into the lives of the people who lived there, and the degree of preservation led the researchers to pinpoint the timing of the eruption, based on archaeobotanical record.

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It isn't every day that we learn something that fundamentally changes how we understand our world. But for volcanologists across the globe, such a revelation has occurred.

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New research reveals more about the magnitude of January eruption, as researchers call for better preparedness The eruption of the Hunga Tonga-Hunga Ha'apai volcano in January created an initial wave 90 meters high -- almost the height of the Statue of Liberty (93m). Tsunami expert calls for better warning systems to detect volcanic eruptions, saying systems are '30 years behind' comparable earthquake detection tools.

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While funding is pumped into preventing low-probability scenarios such as asteroid collision, the far more likely threat of a large volcanic eruption is close to ignored -- despite much that could be done to reduce the risks, say researchers.