Phys.org: Earth science

Massive blooms of Sargassum seaweed that have inundated coastlines across the Atlantic since 2011 likely originate off the coast of West Africa—forming years before they are visible and overturning long-standing assumptions about where these events begin.

A new look at the Juan de Fuca tectonic plate beneath the coast of northern Oregon suggests this subducting slab is shallower than previously thought, with impacts on potential peak ground shaking during a Cascadia megathrust earthquake.

Scientists from UC San Diego's Scripps Institution of Oceanography and the Centro para la Biodiversidad Marina y la Conservación in Mexico have developed a tool that identifies mangrove patches facing the greatest risk of degradation. The tool, called the Mangrove Threat Index and described in a study published in the journal Frontiers in Ecology and the Environment, aims to provide an empirical argument for conservation before vulnerable ecosystems are lost rather than after, said the researchers. The index yields a single number that local planners and communities can use to prioritize specific mangrove patches for protection.

A microscopic green pigment can provide major insights into how severe tropical cyclones called typhoons impact water flow and ecosystems. Called chlorophyll a, the pigment is responsible for absorbing light and initiating the photosynthesis process for algae, other plants and some bacteria. The amount of chlorophyll a in a body of water acts as a proxy measurement for the organisms that feed on it, with sharp increases or decreases indicating a disrupted ecosystem.

Powerful cyclones can push seawater miles inland, threatening densely populated communities and critical infrastructure built along coastal areas. A combination of exposure and complexity makes the Bay of Bengal in Southeast Asia a powerful test case for scientists seeking to better understand how tides, storm surge, river flows and sea level rise interact to drive extreme coastal flooding.

As future shifts in climate lead to more rain and less snow in the western United States, new research finds that water will move faster through a landscape, likely leading to negative impacts on summer water levels and water quality.

The Atlantic current system, or more formally the Atlantic Meridional Overturning Circulation (AMOC), is more likely to weaken than previously thought. That's the conclusion of a new study published in the journal Science Advances, which used more refined modeling techniques to get a clearer picture of the future. If these new projections are correct, the consequences could be severe, particularly for Europe and Africa.

A new study by University of Hawai'i at Mānoa researchers revealed that Waikīkī is facing a fundamental shift in flood hazards as sea levels rise—transitioning from a flooding that is driven primarily by rainfall to events increasingly dominated by tidal processes.

When the edge of a Greenland glacier breaks off into the sea to become an iceberg, can a global seismic network "hear" it? The answer is yes—but only if the event is a large one. And it helps to pair the resulting surface seismic waves with satellite observations to get the best overall chance at detecting calving tidewater glaciers, researchers said at the 2026 SSA Annual Meeting.

Using self-developed drones and advanced sensors, researchers can now see both under the snow and into the ground. The scientists' goal is to reduce societal risk and environmental encroachment.

Sea ice is not just solid frozen water. It's riddled with tiny pockets and channels of liquid brine. Whether those pockets connect to form pathways determines whether seawater, nutrients and gases can move through the ice, according to decades of research by University of Utah mathematician Ken Golden.

Dramatic droughts linked to the decline of the Classic Maya civilization approximately 800 to 1000 CE may not have required any external trigger, according to a new climate modeling study. Instead, they could have emerged from Earth's own natural climate variability—shifts within the climate system that, when aligned, are capable of producing prolonged dry periods on their own.

Because methane has around 80 times the warming potential of CO2 over a 20-year period, it has been a major focus for climate action groups. The Global Methane Pledge, launched at COP26 in November 2021, aims to cut human-caused methane emissions by 30% by 2030.

Organic soils cover less than 9% of Norway's land area, and about 65,000 hectares are currently used as agricultural land. Emissions from these areas are presently estimated at more than 2 million tons of CO₂ equivalents per year. This is equivalent to the emissions from 400,000 fossil-fueled cars.

Although the fundamental constitutive laws for steel and concrete were established more than a century ago, weak layers in snow remain a mystery. There are currently two theories about how they fail. A study published in Geophysical Research Letters has now identified a clear favorite.

New research reveals a powerful yet overlooked driver of climate change: intensifying ocean eddies. These swirling currents—that break off from major currents—are redistributing heat and nutrients in the ocean and amplifying climate extremes in key coastal ecosystems.

A common mineral hiding in plain sight could hold the key to making copper production cleaner, faster and more efficient, just as global demand for the metal surges to power the energy transition. In an article published in Nature Geoscience, researchers from Monash University's School of Earth, Atmosphere and Environment describe why chalcopyrite, the source of around 70% of the world's copper, has remained so difficult to process, and how its hidden chemistry could be harnessed to unlock more sustainable extraction.

Models of glacial flow and retreat rely on estimates of glacial ice viscosity, the measure of the ice's resistance to flow. Ice viscosity is dependent on the stress applied to the glacier. Most ice sheet models use a standard equation to model ice flow that includes the variable n, called the stress exponent. A larger value of n means ice viscosity is more sensitive to changes in stress. For decades, glaciologists have, almost exclusively, used an assumed n value of 3 in the models they use to predict ice flow.

Coastal groundwater is a key source of drinking water in many regions of the world. However, it is threatened by overabstraction and the potential for salinization. Rising sea levels are further exacerbating the situation. This is demonstrated by a recent study published in Nature Water by a research team led by Professor Robert Reinecke from the Institute of Geography at Johannes Gutenberg University Mainz (JGU) and Annika Nolte from the Climate Service Center Germany (GERICS) in Hamburg.

Mark Clementz, a professor in the University of Wyoming Department of Geology and Geophysics, and colleagues have produced a compelling study that shows that an increase in volcanic activity in the Andes in the Late Miocene Epoch likely resulted in a cooling of Earth between 5.4 million and 7 million years ago. Their findings are in a new article, titled "Andean volcanism, ocean fertilization, marine ecosystem turnover, and global cooling in the Late Miocene," published in Communications Earth & Environment.