Phys.org: Earth science

Changes in nutrient dynamics caused by rising water temperatures and altered stratification patterns due to climate change are promoting the growth of harmful algal blooms. This is the outcome of a new long-term study led by the University of Bayreuth and conducted in the Franconian Lake District. The researchers report their findings in the journal Water Resources Research.

Antonio has spent the past seven years running toward fires that most others run from. A firefighter in the Brazilian Amazon since 2019, he works inside the Chico Mendes Extractive Reserve, one of the most biodiverse places on Earth. But things are changing, and fast. "2024 was the most extreme year for fires," Antonio said. "I had never seen anything like it. The forest burned like dry pasture—it was frightening for those of us who risk our lives to protect it."

The conversion of Brazil's native biomes into agricultural areas has resulted in an estimated loss of 1.4 billion tons of soil carbon. This amount is equal to the emission of 5.2 billion tons of carbon dioxide (CO₂) equivalent, a unit of measurement used to standardize the emission of different greenhouse gases, and was calculated based on data collected from studies conducted over the past 30 years.

Venice has coexisted with the sea throughout its 1,500-year history, perhaps better than any other city on Earth. Yet over the past century it has flooded increasingly often, as the sea rises and the city itself sinks under its own weight.

A study led by Wageningen University & Research shows that human interventions have significantly changed tides in river estuaries over the past centuries. In many regions around the world, the difference between high and low tide has increased, and the tidal wave is moving inland faster. These changes often appear to have a greater impact than the effects of sea-level rise.

Imagine your favorite sunny beach. Anywhere will do. You look out and see the ocean stretching to the horizon. To a glaciologist, that view is not just water; it's melted ice. Our new study shows that the best case sea-level rise scenarios may now be out of reach. The work is published in the journal Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences.

Thousands of slips in Tairāwhiti in January. The loss of eight lives in the Bay of Plenty later that month. And, days ago, landslides that damaged homes, forced evacuations and blocked roads across the North Island.

The South Asian summer monsoon sustains billions of people today. For a long time, the prevailing scientific view has held that the formation and intensification of the South Asian summer monsoon were primarily controlled by the rapid uplift of the Tibetan Plateau. However, geological records present a long-standing puzzle from the Early to Middle Miocene (25 to 15 million years ago): the South Asian monsoon rainfall was remarkably strong, even though the Somali Jet—the primary wind system transporting moisture—was relatively weak.

Central Mongolia's Hangay Mountains rise more than four kilometers above sea level, forming a dramatic dome that shapes the region's climate. But for decades, geologists have been puzzled: What caused this massive mountain range to form so far from any active plate boundary? Unlike the linear Himalayas, which are still rising from the collision of India and Asia, the dome-shaped Hangay Mountains show little internal deformation, suggesting a different and previously unknown mechanism.

Scientists have discovered a Jurassic tectonic plate boundary that could help to predict what the planet might look like millions of years into the future. Dr. Jordan Phethean, Senior Lecturer in Earth Sciences at the University of Derby, is part of a team of researchers that has unveiled a previously unrecognized, major tectonic feature of Earth, in East Africa. The new structure, which has been likened to an ancient version of the San Andreas fault in California, was partially responsible for the breakup of the supercontinent Gondwana 180 million years ago in the Jurassic period.

While analyzing strong-motion data close to fault lines, a group of researchers at Kyoto University noticed something unexpected: a negative phase in the waveforms, a pattern that did not conform to the existing interpretations of rupture dynamics. Its regular appearance in the records near rupture end points suggested that the team might be seeing something new. The study has been published in Science.

Geopolitical tensions in Eastern Europe underscore the urgency of addressing the climate and radiological consequences of a regional nuclear conflict. Even a small-scale nuclear conflict at the Ukraine–Russia border could cause years of severe global climate disruption and radioactive fallout across much of the world, new research suggests.

New York, New Orleans and Miami are among the eight cities along the US Gulf and Atlantic coasts facing the highest flood risk, according to a new study published in Science Advances. Scientists developed a new AI-driven framework and combined it with historical flood-damage data to not only identify high-risk coastal areas but also pinpoint the underlying factors driving that risk.

Thousands of earthquakes affecting Portugal's São Jorge Island in the Azores in March 2022 were triggered by a vast sheet of magma (molten rock) rising from more than 20km below Earth's surface and stalling just 1.6km beneath the island, according to a new study led by UCL (University College London) researchers.

Scientists at the University of Melbourne have uncovered for the first time how Australia's iconic Twelve Apostles were formed, finding tectonic plate movements over millions of years lifted and tilted the giant structures out of the sea.

Eastern Africa's Turkana Rift is both a hotbed for fossil discoveries of our earliest ancestors and a literal hotbed of volcanic activity caused by shifting tectonic plates. Now researchers have found that Earth's underlying crust in the region has been significantly thinned, presaging Africa's eventual breakup—and with that finding, the researchers offer a new perspective on how Turkana's world-famous fossil record of human evolution came to be. The findings are published in Nature Communications.

Too much stress can make even a rock crack. But before rocks reach their breaking point, they "sigh" a chemical warning by releasing nuclides, a type of atom defined by the number of neutrons as well as protons in the nucleus. Scientists have studied these naturally occurring geochemical emissions for more than half a century, but struggled to link nuclide release to the timing of rock breakage. Now, an international team of scientists from universities in China (led by Xin Luo at Hong Kong University and Yifeng Chen at Wuhan University) and the United States (led by Michael Manga at the University of California, Berkeley) has cracked that mystery, by creating a model to connect nuclide signal fluctuations to progressive changes in rock structure that lead to critical failure.

For more than 100,000 years, the Methana volcano in Greece appeared dormant. No lava, no explosions, no ash clouds. It appeared extinct, like many other volcanoes today. An international research team led by ETH Zurich has reconstructed a detailed, long-term history of the Methana volcano. Their work is published in the journal Science Advances, and their conclusion is striking: While Methana appeared silent at the surface, enormous amounts of magma were steadily accumulating deep within its magma chambers.

Lakes are often described as "hotspots" in the global carbon cycle, yet quantifying their "breath"—the exchange of carbon dioxide (CO2) between water and the atmosphere—has long been notoriously difficult due to extreme variability across time and space and a shortage of long-term, high-resolution observational data. As a result, they have remained as a missing piece in regional carbon accounting.

Mud-rich coastlines could face a greater tsunami risk, at least that may have been the case for the 2011 Tōhoku-oki tsunami that killed more than 19,000 people and led to the Fukushima Daiichi nuclear disaster. According to a new study published in the Journal of the Geological Society, mud may have made the catastrophic ocean waves more destructive than they might otherwise have been.