Phys.org: Earth science

Slow roiling convection currents deep within Earth's mantle, which are associated with the movements of tectonic plates, also deform the material of the mantle itself. Now, a new study in The Seismic Record confirms that much of this deformation in the lowest level of the mantle occurs where researchers think there may be deeply subducted tectonic slabs.

Some newly published findings from an Idaho State University professor and his colleagues point out how changes to currents an ocean away can impact climates on the other side of the globe. The new paper published in Nature Communications explains how Bruce Finney, professor in the departments of biological sciences and geosciences at ISU, and his collaborators, Lesleigh Anderson, research geologist with the United States Geological Survey, and W. Brad Baxter, Idaho State alum, came to understand how shifts in currents in the Atlantic Ocean led the climate of Alaska to cool, especially in winter, roughly 13,000 years ago.

Researchers at the Institute of Water and Environmental Engineering (IIAMA) at the Universitat Politècnica de València have developed an advanced system for seasonal forecasting of meteorological droughts that enables these events to be predicted up to six months in advance, providing a key tool for water management and early warning in semi-arid regions, such as the Júcar river basin.

In the aftermath of the latest bout of extreme rainfall across New Zealand's upper North Island, there were some familiar scenes.

A growing network of meltwater lakes at the edge of the Greenland ice sheet is accelerating the flow of major glaciers, potentially increasing the pace of global sea-level rise. Warmer air and sea temperatures have led to the loss of around 264 gigatons of ice every year in Greenland since 2002, causing sea levels to rise by 0.8 millimeters annually. But a new study by the University of Leeds examining glacier behavior across the entire ice sheet has highlighted a lesser-known feature that is amplifying this mass loss—the freshwater lakes forming as the ice retreats.

Rivers are rarely the calm, orderly streams we imagine on maps. Over time, their winding paths—called meanders—shift, bend, and occasionally snap off in sudden "cutoff" events that shorten loops and reshape the landscape. While scientists have long suspected that such cutoffs inject a dose of unpredictability into river evolution, a new study published in Communications Earth & Environment demonstrates that these abrupt events are, by themselves, enough to produce chaos in river channels.

Earth's "gold kitchen" lies deep beneath the seafloor. Island arcs, whose volcanoes form above subduction zones where one oceanic plate sinks beneath another, are often particularly rich in gold. The reasons for this have long been debated.

Researchers have uncovered new evidence that short-lived spikes in ocean phosphorus may have played a major role in two of the most severe marine extinctions in Earth's history. Dr. Matthew Dodd from The University of Western Australia's School of Earth and Oceans is lead author of the study published in Nature Communications, which sheds new light on how nutrient disruption can destabilize life, climate, and ocean chemistry on a global scale.

The Syrian civil war, which began in 2011, caused widespread population displacement and infrastructure damage. However, it has also led to an unintended environmental effect with notable changes in the country's landscape, according to a new study published in Geophysical Research Letters. Among the concerns are the complex impacts of wars on water resources. These repercussions can be direct, such as wastewater pollution and destruction of water infrastructure, or indirect, including increased deforestation, soil erosion, and abrupt cropland losses.

In a first-of-its-kind study, a team of researchers led by geoscientist Michael Rawlins at the University of Massachusetts Amherst has shown in fine-grained detail what happens when Arctic permafrost thaws. Focusing on a Wisconsin-sized area of Alaska's North Slope containing hundreds of rivers and streams flowing into the Beaufort Sea, the team analyzed 44 years of model data at one-kilometer grid resolution, revealing how massively runoff is increasing, the increased loads of previously frozen carbon flowing through northern Alaska's rivers and how the thawing season has extended into late-summer and fall.

Communities worldwide rely on reservoirs for drinking water, hydroelectric power, irrigation, and more. These critical freshwater resources are affected by seasonal and long-term changes; water levels in reservoirs can dip during hot summer months or due to prolonged drought, or can flood after a particularly strong storm. Despite their importance, there are key gaps in our knowledge of reservoir structure and dynamics. Two recent papers published in Scientific Data use Landsat data to help fill in those gaps.

The circular economy concept is often thought of as a model to eliminate waste and pollution—but when applied thoughtfully, circular approaches can create jobs, strengthen local economies, improve public health and more, according to new research led by Charles Darwin University (CDU).

As global temperatures climb, rainfall patterns are shifting in ways that could put water resources and agriculture under increasing strain, a new study published in Water Resources Research suggests.

Scientific expeditions require months of planning before scientists can acquire the first data. A bark cuts through the Arctic silence, waking Anna up. She slept only three hours after collecting the last sample. Anna reaches for her rifle, exits the tent, and steps onto the midnight ice. She pets the guard dog she rented a few days earlier. It might be a false alarm, but she scans the darkness for polar bears, hoping her training pays off. She cannot afford to lose the samples. Nor her life.

In recent years, the Prairies have seen bigger swings in climate conditions—very wet years followed by very dry ones. That makes an already unpredictable landscape even harder to forecast, with real consequences for flood preparedness and water quality.

Wild animals are not just inhabitants of the natural world. Many also act as natural landscape engineers, reshaping Earth's surface as they burrow, feed, and build shelters that move soil and sediment across ecosystems. From animals disturbing riverbeds to burrowing species redistributing soil, wildlife constantly modifies the physical structure of landscapes through everyday activities.

Earth has already exceeded its ability to support the global population sustainably, with new research warning of increasing pressure on food security, climate stability, and human well-being. However, slowing population growth and raising global awareness could still offer humanity some hope.

Volcanoes are both captivating and disastrous. Most are likely familiar with the common short-term dangers associated with them: explosive forces, lava, and even atmospheric particles disrupting air traffic. But researchers also explore longer-term impacts of eruptions, as their contributions to broader climate patterns are important, but not well understood. For example, it's known that ejected material can reach high into the atmosphere and cause local or even global cooling to some degree.

Experiments by University of Leeds researchers, published in Earth's Future, have shown that thawing of permafrost makes it between 25 and 100 times more permeable, allowing more climate change forcing gases to escape.

Some Arctic regions regain their "greenness" within a decade of a sudden permafrost collapse, while others can take a century or more to recover, researchers report in a new study. The difference is directly related to each site's gross primary productivity, a measure of its photosynthetic capacity, the researchers discovered. This finding will allow scientists to accurately predict how long it will take a specific site to recover after a permafrost collapse.