Phys.org: Earth science

A new review in Limnology and Oceanography led by scientists at UC San Diego's Scripps Institution of Oceanography warns that the rapid loss of oxygen from the ocean and other aquatic ecosystems is pushing Earth toward an "unsafe space," with consequences that could be irreversible on human timescales.

Alberto Borges, oceanographer at the University of Liège, has conducted a comparative study in Belgium and Africa on the microbial oxidation of methane in rivers, a natural process in which certain bacteria consume this powerful greenhouse gas before it is released into the atmosphere. His research reveals that this biological filter, which is more active in African rivers than in Belgian rivers, remains insufficient to offset the rise in methane emissions expected because of global warming and nitrate pollution.

An international team of researchers, including scientists from Utrecht University and the University of Maryland, has reconstructed the concentration of clumped isotopes of methane in air from the past for the first time. This provides new insights into how atmospheric methane concentrations have changed since the start of the industrial era, around 1850. For the study, the scientists used air that was roughly 40 years old, preserved in compacted snow (firn) in Greenland. The results were published in Science Advances.

Two weeks ago, the Philippine Institute of Volcanology and Seismology recorded three distinct, short-lived explosions in less than five minutes at Taal Volcano. The eruption sent a column of ash and steam up to 1.2 km (0.75 miles) into the air.

A team of international scientists sets sail Thursday from Britain for Greenland to study its rapidly melting ice using drones, mini-submarines and autonomous swimming robots.

A new study led by the University of Barcelona reveals that freshwater exported from the Black Sea to the Aegean Sea triggered major environmental changes across the Eastern Mediterranean.

Paleontologists in China have discovered the oldest chemically verified amber ever found, dating to 385 million years ago. That's approximately 140 million years before dinosaurs roamed Earth. The previous record holder was an amber sample from the Late Carboniferous period, dating to about 320 million years ago.

Heavy precipitation becomes more intense with every degree Earth warms. This affects flooding. Using hourly data from 384 rivers in the Alps, researchers from the WSL Institute for Snow and Avalanche Research SLF modeled how flooding will change by the end of the century. Their projections are significantly bleaker than earlier ones. The findings are published in the journal Science Advances.

While particulate matter air pollution from human activity in transportation, households and industry is decreasing in Europe, thanks to strict regulations, another source is developing in the opposite direction: desert dust.

Wetlands have shaped human life in Europe since ancient times. These ecosystems provided essential resources and safe havens for plants and animals, and in many regions they also held spiritual and ritual significance. For millennia, wetlands covered vast parts of the European continent.

New Antarctic research shows the deepest layer of the Southern Ocean is shrinking faster than scientists realized, with the rate of change accelerating over the past decade. This is of worldwide significance because as it sinks and fills up to 40% of the global ocean volume, the cold, dense water known as Antarctic Bottom Water (AABW) drives Earth's system of currents and regulates our climate.

Australia's ocean territory is vast and covers an area more than 1.5 times the nation's landmass. Within these waters is a diversity of resources, marine species and habitats. And they're deep. Excluding Antarctic waters, 70% of Australia's ocean territory is deeper than 1,000 meters (3,281 feet), and nearly 50% is deeper than 3,000 meters (9,843 feet).

In the aftermath of the devastating July 4, 2025, floods that took 139 lives in Central Texas, an associate professor at The University of Texas at Austin set out to make a new type of outdoor flood alarm: a low-tech, loud alarm that anyone could "set and forget"—just like a smoke detector.

When most people hear the phrase "ocean acidification," they think of coral reefs, shellfish or declining fisheries. Those concerns are real. But while working on our recent research, I found myself asking a different question: What if ocean acidification is telling us something much bigger than the health of marine ecosystems?

Ocean tides push upstream along coastal rivers, in some cases reaching hundreds of kilometers (hundreds of miles) inland. These inland stretches are known as tidal rivers, and they're the scene of complex interactions between the river current and tidal oscillations. When rivers flood, tidal dynamics can sometimes add to a river's height, increasing overall peak water levels and amplifying flooding.

Methane (CH4) is a potent greenhouse gas whose concentration in the atmosphere has risen sharply in recent decades. Wetlands are the largest natural source of methane to the atmosphere, but large uncertainties remain about how much methane comes from wetlands and how these emissions may increase in response to a changing climate. Tropical wetlands, including those in the Amazon, produce substantial amounts of methane, but accurately estimating their emission sources and magnitudes remains difficult. One reason is the lack of measurement data, especially in the tropics, where extensive cloud cover interferes with satellite observations and ground-based measurements are sparse.

In the heart of the Congo Basin's Cuvette Centrale, a large depression that hosts the world's largest tropical wetland complex, lie two vast, shallow blackwater lakes, Lake Tumba and Lake Mai Ndombe. Together, they are roughly the size of 420,000 football fields.

Many parts of Western Europe are currently wilting under a heat wave. These blistering spells can last for a week or more, and although they are common in most summers, it is difficult to predict how long they will last.

A Florida State University paleoclimatologist led the creation of a global database hosting thousands of seawater isotope measurements collected over almost 50 years that will aid scientists in generating more accurate climate reconstructions and predictions.

Contrary to conventional geological thinking, the Hawaiian mantle plume has gotten hotter by about 250°C (480°F) over the past 47 million years. This discovery, led by Earth scientists at the University of Hawai'i at Mānoa, reverses the long-held idea that hotspots start out very hot and progressively cool over time. The study, published recently in Earth and Planetary Science Letters, also found that heat surges produced the two largest volcanoes along the Northwestern and Main Hawaiian Island chain.