Phys.org: Earth science

Using a new method to track groundwater levels and greenhouse gas emissions, researchers uncover the climate impact of Southeast Asia's peatlands. In Indonesia, Malaysia, and other parts of Southeast Asia, vast areas spanning up to 300,000 square kilometers have emerged over thousands of years as plants grow and thrive in dense tropical peat swamp forests, then die and slowly decompose in waterlogged, low-oxygen conditions.

Australia has always had heat waves. But this week's heat wave in southeastern Australia is something else. Temperatures in some inland towns in South Australia, New South Wales and Victoria were up to 20°C above average for the time of year, which meteorologists described as "incredibly abnormal." Victoria's heat record toppled after Walpeup and Hopetoun hit 48.9°C. The heat is set to continue until Saturday in some areas.

This week, Victoria recorded its hottest day in nearly six years. On Jan. 27, the northwest towns of Walpeup and Hopetoun reached 48.9°C, and the temperature in parts of Melbourne soared over 45°C. Towns in South Australia also broke heat records.

Far from simply a source of unstructured online content, disaster management in the digital age can be supported by careful analysis of online social-media data, suggests a paper published in Natural Hazards and Earth System Sciences (NHESS) titled "Social Media for Managing Disasters Triggered by Natural Hazards: A Critical Review of Data Collection Strategies and Actionable Insights."

Researchers at Concordia have developed a new method of measuring the amount of usable water stored in snowpacks. The comprehensive technique, known as snow water availability (SWA), uses satellite data and climate reanalysis techniques to calculate snow depth, snow density, and snow cover across a wide swath of Canada and Alaska.

Should growing glacial lakes be used for energy production and water supply—or remain protected as ecologically valuable systems? A research team from the University of Potsdam, together with partners from the University of Leeds, has recorded the distribution and volume of glacial lakes worldwide. Their findings allow various usage scenarios to be derived, particularly in areas where the largest glaciers still exist today. Their article has been published in Nature Water.

A new study led by climatologists at the University at Albany has found that extreme heat waves across the Caribbean are becoming significantly more frequent, longer and severe. This study examined extreme summer heat waves in the Caribbean over the last five decades, focusing on their causes and how they have changed over time.

Forecasting volcanic eruptions in time to alert authorities and populations remains a major global challenge. In a study published in Nature Communications, researchers and engineers from the Institut de Physique du Globe de Paris (IPGP) and the GFZ Helmholtz Centre for Geosciences present a new detection method, called "Jerk," using a single broadband seismometer. It is capable of identifying, in real time, very early precursor signals of volcanic eruptions generated by subtle ground movements associated with magma intrusions.

For decades, families in communities around Johannesburg have been living close to huge gold mining waste dumps. For many residents, the dust that is released there is just part of everyday life—but it can contain natural uranium compounds that come to the surface with the mined rock. A new study in the journal Environmental Geochemistry and Health reveals how this exposure is reflected in children's hair.

People living on the low-lying shores of the Bristol Channel and Severn estuary began their day like any other on January 30, 1607. The weather was calm. The sky was bright.

The King's Trough Complex is a several-hundred-kilometer-long, canyon-like system of trenches on the North Atlantic seafloor. Its formation was long thought to be the result of simple stretching of the oceanic crust. An international research team led by the GEOMAR Helmholtz Center for Ocean Research Kiel has now shown that the so-called "Grand Canyon of the Atlantic" was formed about 37 to 24 million years ago through the interplay of a temporarily existing plate boundary and an early branch of the Azores mantle plume. Their findings have been published in the journal Geochemistry, Geophysics, Geosystems.

To reduce air pollution associated with ocean transport, the International Maritime Organization tightened restrictions on sulfur content in ship fuel, resulting in an 80% reduction in emissions by 2020. That shift created an inadvertent real-world experiment in how man-made aerosols influence cloud formation over the ocean.

When most of us look out at the ocean, we see a mostly flat blue surface stretching to the horizon. It's easy to imagine the sea beneath as calm and largely static—a massive, still abyss far removed from everyday experience.

Wetlands make up only about 6% of the land area but contain about 30% of the terrestrial organic carbon pool. Therefore, CO2 emissions from wetlands are central to the global climate balance. In Denmark, the plan is to flood 140,000 hectares of low-lying land such as bogs and meadows as part of the Green Tripartite Agreement. Flooding such areas will slow down the decomposition of organic material in the soil and keep the CO2 in the soil rather than allowing it to be released to the atmosphere and contribute to the greenhouse effect. At least, that has been the rationale until now.

A new study suggests the world's oxygen-depleted seas may have a chance of returning to higher oxygen concentrations in the centuries to come, despite our increasingly warming climate.

A relatively simple statistical analysis method can more accurately predict the risk of landslides caused by heavy rain, according to a study coordinated by Brazilian researchers affiliated with the Institute of Mathematical and Computer Sciences at the University of São Paulo (ICMC-USP) in São Carlos and the National Institute for Space Research (INPE). The researchers have validated their strategy based on a real event.

In a critical advance for climate resilience, researchers from The Hong Kong University of Science and Technology (HKUST) have developed an AI model that can predict dangerous convective storms—including Black Rainstorms, thunderstorms and extreme heavy rainfall like those that have hit Hong Kong—up to four hours before they strike. This world-first technology, developed in collaboration with national meteorological institutions and powered by satellite data and advanced deep diffusion technology, improves forecast accuracy by over 15% at the 48-kilometer spatial scale compared with existing systems. This breakthrough strengthens the overall accuracy of the national weather forecasting system and promises to transform early warning systems for vulnerable communities across Asia.

A team of NASA scientists deployed on an international mission designed to better understand severe winter storms. The North American Upstream Feature-Resolving and Tropopause Uncertainty Reconnaissance Experiment, or NURTURE, is an airborne campaign that uses a suite of remote sensing instruments to collect atmospheric data on winter weather with a goal of improving the models that feed storm forecasts. This combination of instruments will also serve as a proxy to demonstrate the potential to collect similar observations from space.

Deforestation is having a more devastating effect on the Amazon rainforest than earlier data suggested. While cutting down large swaths of trees destroys vital habitats, it also harms the region's ability to generate its own rainfall. According to a new study published in the journal Nature, the Amazon could reach a tipping point and experience major forest dieback (where large areas of the rainforest dry out and turn into a savanna) sooner than previously thought.

The cycling of water within Earth's interior regulates plate tectonics, volcanism, ocean volume, and climate stability, making it central to the planet's long-term evolution and habitability and a key scientific question. While subducting slabs are known to transport water into the mantle, scientists have long assumed that most hydrous minerals dehydrate at high temperatures, releasing fluids as they descend.