Phys.org: Earth science

A heat wave lasting four months, followed by water shortages and crop failures. This is England in the 13th century, not the 21st. What is often called the Medieval Warm Period saw elevated temperatures in many parts of the world between the 10th and 13th centuries.

In recent summers, wildfire smoke has been inescapable across Wisconsin, drifting south from Canada and leading to long stretches of poor air quality. Whether that smoke clears or lingers is often influenced in part by the atmospheric boundary layer—the lowest part of the atmosphere, where airborne particles mix and move.

Anyone who has boiled a pot of water understands that it takes both time and energy to raise the temperature, so it may come as a surprise to learn that scientists have long treated marine heat waves (MHWs) as isolated events. New research led by William & Mary's VIMS & Batten School is challenging that narrative by providing a framework to characterize an ecosystem's cumulative heat exposure from MHWs and the extended periods of warm water that precede and follow them.

In a new study, researchers at Leipzig University have identified a major cause of the unusually severe summer soil drying and rising temperatures across Europe. They found that much of the trend can be attributed to changes in atmospheric circulation patterns—that is, shifts in the weather regimes that typically occur over Europe. These changes account for around 55% of the observed summer drought trend. Specifically, more frequent and persistent high-pressure systems have brought drier conditions and reduced rainfall.

The seafloor plays an important ecological and societal role. Understanding the processes that shape this environment will help guide conservation policy and decision-making about underwater infrastructure and geohazards.

New research from the University of St Andrews has found that metal production carbon footprints could be more than 10 times higher than previously estimated, with serious implications for the ambition to reach net zero.

About 90% of the Aral Sea has dried up. The exposed sediments have already released enormous amounts of carbon dioxide (748 megatons) since 1960. However, through restoration, the lake could once again become a carbon sink. This is shown by a study by the Centre for Advanced Studies of Blanes (CEAB-CSIC), published in Science, in which the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) participated. Hydrological restoration of the desiccated sediments would prevent emissions equivalent to Spain's total emissions over three years—namely, around 605 megatons, according to the research team's calculations.

A pioneering study has revealed that by the turn of the next century, at least half a million more people in the UK will be at risk of coastal flooding—a 25% increase compared with now. The research, led by the Met Office and the University of Bristol, quantifies for the first time the scale of the UK population at risk from coastal flooding under future sea level rise projections.

Sustained supershear earthquake ruptures produce distinct ground-motion characteristics compared with subshear earthquakes, according to a study published in the Bulletin of the Seismological Society of America, with potential implications for current building codes and ground-motion models.

A team of Virginia Tech geoscientists has found a new way to examine the widespread effects of dams on river temperatures: using Landsat thermal infrared imagery to gather data on rivers across the United States. By using satellite imagery instead of site-specific, on-the-ground measurements, researchers can draw from a much larger pool of data.

In much of Asia, the effects of climate change are felt through an increased frequency of extreme weather events, especially water-related ones. Droughts are becoming more common in mainland Southeast Asia, while periods with unusually large amounts of rainfall are increasing in Central Asia. Rice University's Na Wang and Sylvia Dee were interested in understanding whether these two extremes were related, despite being geographically distant. The researchers' findings were recently published in Nature Geoscience.

Cardiff University leads a multidisciplinary research collaboration representing academia and multiple nongovernmental organizations (NGOs) to explore Somalia's 2023 El Niño floods and lessons learned from a similar event in 1997. The research, which has yet to undergo peer review, was released as a preprint on Earth ArXiv because academics believe the situation ahead of this year's Deyr season—the secondary, shorter rainy season in the Horn of Africa, typically running from October to December—could be much more serious, and the findings have urgent implications for planning now.

A recent study, published in Geophysical Research Letters, combines historical satellite observations with atmospheric reanalysis data to construct a multidecade record of low-cloud cover in the hope of improving current climate models.

Natural hydrogen is considered a potential low-carbon energy source. But how much is generated underground—and how quickly? An international research team led by the LIAG Institute for Applied Geophysics in Hannover has published the first process-based estimates for the Western Pyrenees and Northern California in Nature Communications. The calculated production rates are lower than earlier theoretical estimates. The study's new evaluation method, through the open-source tool PoNHy, allows more realistic assessments and can be applied to other regions to identify promising geological systems more precisely and evaluate their potential.

The end-Triassic mass extinction, 201 million years ago, is linked to volcanism that resulted from the break-up of Pangea and which pumped out vast amounts of CO2 into the atmosphere, causing extreme global warming of 5 to 10 degrees Celsius. As a result, tree-dominated vegetation collapsed and the highly disturbed landscapes were colonized by ferns that formed savannahs across large swaths of what is now Northwest Europe.

New analysis shows that a "pause" in Arctic winter sea ice decline seen in the early 2020s has ended following record lows in 2025 and early 2026. The study, led by the University of Southampton in collaboration with the National Oceanography Center (NOC), adds the most recent satellite observations to sea ice coverage trends during the winter growth and peak phases of the Arctic sea ice cycle.

Researchers have copied massive quantities of publicly available climate and environmental data from NASA onto a Swiss supercomputer to train artificial intelligence models—and for safekeeping amid U.S. funding cuts.

Some of the most extraordinary gems ever found belong to a rare class of diamonds known as CLIPPIRs (Cullinan-like, Large, Inclusion-Poor, Pure, Irregular, Resorbed). They make up less than 1% of all diamonds on Earth and include three of the largest diamonds ever recovered: the Cullinan, at 3,106 carats (1.4 pounds), found at the Premier mine in South Africa; the 1,111-carat Lesedi La Rona, discovered at the Karowe mine in Botswana in 2015 and sold for $53 million in 2017; and the 2,492-carat Motswedi (1.1 pounds), recovered from the Karowe mine in 2024.

The Great Salt Lake is separated by a 20-mile (32-kilometer) causeway into a super-salty north arm and a less-salty south arm, with each hosting distinct communities of extremophiles. These organisms mingle at a gap in the causeway, designed to regulate salinity, that has provided microbiologists with an unusual and rich opportunity to study how human activities and weather disturbances affect microbial communities in extreme environments.

AI companies increasingly want to move their operations into space. Elon Musk's SpaceX has applied to launch over a million AI data center satellites and ultimately build them on the moon.