Phys.org: Earth science

New Curtin-led research has revealed that water played a far bigger role than previously thought in shaping Earth's first continents, transforming the planet's early crust and helping to build the landmasses we see today.

Mid-ocean ridge basalts (MORBs), located far from subduction zones, are typically thought to be unaffected by subduction processes. However, some MORBs display arc-like geochemical signatures—including negative Nb anomalies and elevated H2O/Ce and Ba/Th ratios—referred to as "ghost-arc signatures."

The sun may rise every morning, but the amount of sunlight reaching Earth's surface can substantially vary over decades, according to a perspective article led by an international research team.

Since December, Raphel Abraham has been struggling to cope with life in his flooded home on the banks of Vembanad Lake, in Edakochi, southern India.

The El Niño phenomenon in the South Atlantic and Benguela current, which flows along the west coast of southern Africa, have a significant impact on the tropical Atlantic region, leading to extensive effects on local marine ecosystems, African climates, and the El Niño Southern Oscillation. No one has been able to predict warm events in this region until now.

Much of Earth's heat uptake is passed to the ocean, making ocean heat content key for understanding long-term climate patterns. Ocean heat content is typically lower during ice ages and rises during warmer periods of glacier retreat. Over the past 1.2 million years, ice ages and interglacials have occurred in cycles lasting about 100,000 years, and we are currently in an interglacial period after the Last Glacial Maximum occurred about 20,000 years ago.

Scientists at the University of Miami's Alfred C. Glassell Jr. SUrge‐STructure‐Atmosphere INteraction (SUSTAIN) laboratory conducted a first-of-its-kind study into how waves form and increase in windy and hurricane conditions. The research, which reconstructs the two-dimensional profile of pressure and airflow above wavy surfaces, provides new insights into understanding ocean wave growth and its broader implications for weather forecasting and coastal resilience.

A little over 5 million years ago, water from the Atlantic Ocean found a way through the present-day Strait of Gibraltar. According to this theory, oceanic water rushed faster than a speeding car down a kilometer-high slope towards the empty Mediterranean Sea, excavating a skyscraper-deep trough on its way.

Deep-sea mining (DSM) not only poses significant environmental, social, and economic risks that may have far-reaching implications for coastal communities and Small Island Developing States (SIDS), it is also likely to negatively affect the business community, including insurers and investors, says a new study by researchers from the University of British Columbia and the Dona Bertarelli Philanthropy.

In an article published in Science Advances, a collaborative team led by the Woods Hole Oceanographic Institution (WHOI) presents a never-before-seen image of an oceanic transform fault from electromagnetic (EM) data collected at the Gofar fault in the eastern Pacific Ocean.

A new study has shed light on the highly variable and climate-sensitive routes that substances from Siberian rivers use to travel across the Arctic Ocean. The findings raise fresh concerns about the increasing spread of pollutants and the potential consequences for fragile polar ecosystems as climate change accelerates.

As climate change increases, so does the pressure on humanity to remove carbon dioxide (CO2) from the atmosphere—possibly with the help of the oceans. But which of the proposed marine CO2 removal and storage options should be used?

O'ahu's sandy beaches are at risk. New research from the Coastal Research Collaborative (CRC) at the University of Hawai'i (UH) at Mānoa determined that 81% of O'ahu's coastline could experience erosion by 2100, with 40% of this loss happening by 2030. Importantly, these forecasts of shoreline erosion are more extreme than previous studies indicated for Oʻahu. The study was published recently in Scientific Reports.

A recent study led by Prof. Chen Yaning from the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences has found that climate warming is increasing flood risks from rain-on-snow (ROS) events in High Mountain Asia. The study, published in npj Climate and Atmospheric Science, analyzed the distribution, causes, and flood risks of ROS events.

Tropical cyclones are hurricanes that brew over the tropical ocean and can travel over land, inundating coastal regions. The most extreme cyclones can generate devastating storm tides—seawater that is heightened by the tides and swells onto land, causing catastrophic flood events in coastal regions.

Imagine if Earth's history had a mystery novel, and one of its biggest unsolved puzzles was: Where did all the nitrogen go? Scientists have long known that our planet's rocky outer layers—the mantle—are oddly poor in nitrogen compared to other volatile elements like carbon or water. Very strangely, the C/N and 36Ar/N ratios in the bulk silicate Earth (BSE, the whole Earth minus the metallic core) are far higher than those found in the meteorites that supposedly delivered these ingredients during the planet's infancy.

Research led by the Union of Concerned Scientists reports that emissions from the world's largest fossil fuel and cement companies have contributed significantly to both present-day and long-term sea level rise. Products from 122 major producers have contributed up to 37% of the rise in global sea level observed through 2022 and may account for an additional 0.26 to 0.55 meters by 2300.

Sustained scientific observations and monitoring are crucial for measuring ocean change, providing valuable data that contributes to a better understanding of oceanography, biodiversity, and the interconnectedness of global systems, and helps inform decisions about conservation and resource management.

What is the role of dissolved organic matter in the deep sea? In a study relating to this question, researchers from the Universities of Bremen and Oldenburg have investigated the composition of dissolved organic matter (DOM) in detail. Their samples were obtained during an expedition to the Guaymas Basin in the Gulf of California.

Nearly three-fourths of Earth is covered by oceans, making the planet look like a pale blue dot from space. But Japanese researchers have made a compelling case that Earth's oceans were once green, in a study published in Nature.