Phys.org: Earth science

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.

In recent years, residents of Spain, France and the UK have looked up to see an eerie sight: deep orange sunrises and skies thick with a yellowish haze. These hazy skies often deposit "blood rain," rust-colored precipitation that leaves a fine grit on cars and windows.

Both winds and tides inject energy into the ocean. Much of that energy is then transported up to thousands of miles by internal waves: large-scale underwater waves that can travel between ocean basins. Quantifying the amount of energy transported by internal waves and assessing their dynamics are difficult given their location and scale. Still, the question is important because internal wave dynamics interact with the global climate and underwater ecosystems by influencing currents, ocean mixing, and more.

Offshore wind farms are an important pillar of the European Union's strategy for renewable energy—by 2050, the EU aims to increase capacity in the North Sea more than tenfold. A new study by the Helmholtz-Zentrum Hereon shows that the expansion of wind farms can alter the natural transport and deposition of sediments on a large scale and over the long term. The German Bight is particularly affected. The researchers have published their findings in the journal Nature Communications Earth & Environment.

Sea ice is sticking to Alaska's northern coast for less time each year, according to 27 years of data analyzed by University of Alaska Fairbanks scientists. Such landfast ice, which stays attached to the shoreline instead of drifting with winds and currents, also has covered less total area in recent winters.

A new Stanford University study has helped solve a mystery about dramatic swings in sea ice extent around Antarctica.

A new study finds that commercial satellite imagery data often outperforms public data sets when identifying surface water, but that public data sets may be better at detecting water hidden by forest cover. Satellite imagery is a powerful tool for mapping surface water, from the movement of rivers and streams to water levels and even water temperatures. The effectiveness of those satellites depends on their ability to identify water in the images they capture.

Understanding what triggers large volcanic eruptions is crucial for hazard assessment, but the exact mechanism driving these eruptions is still poorly understood. The prevailing theory is that volatile exsolution—gas coming out of magma—is a main driver of eruptions, particularly in volcanoes rich in silica. However, a new study, published in Nature Communications, posits that it is actually gas being dissolved back into the magma that leads to the pressurization needed for large eruptions.

Severe Tropical Cyclone Narelle continues to amaze us with its long journey across northern Australia. This cyclone began life near the Solomon Islands on March 16, when moist air rose rapidly and created a low-pressure zone.

Although volcanic eruptions are spectacular natural events that occur around the world every day, most volcanoes spend the majority of their time not erupting. To accurately forecast volcanic activity, it's important to characterize the magma before an eruption is imminent.

The magma reservoir of the largest volcanic eruption of the Holocene is refilling. This Kobe University insight on the Kikai caldera in Japan allows us to understand giant caldera volcanoes like Yellowstone or Toba more generally and gets us closer to predicting their behavior, too.

New research from a team at Trinity College Dublin has unearthed a cheap and environmentally friendly new option for removing pollutants from our water. The key? Oyster shells that would ordinarily end up in landfill sites after consumption. The research, just published in the journal Science of the Total Environment, shows that waste seashells—especially those from oysters—can capture and remove rare earth elements from polluted water. And what's more, they do it entirely naturally, turning them into stable mineral crystals.