Phys.org: Earth science

Old oil and gas wells may continue to affect the environment long after they have stopped producing, with new field evidence showing that their leakage footprint can be broader and more persistent than surface methane measurements alone reveal. A study led by researchers at The Lyell Centre, Heriot-Watt University, examined persistent methane leakage from a legacy petroleum well in British Columbia, Canada. The team found that while methane emissions at the ground surface were concentrated in a relatively small area and varied through time, the leakage also left a wider detectable signature in the shallow subsurface and surrounding soils.

A recent study published in Advances in Atmospheric Sciences has uncovered a detailed mechanism through which intense storms over the Himalayas contribute to increasing moisture in the lower stratosphere—a layer of the atmosphere crucial to global climate regulation. The research, led by Ph.D. student Li Ming and Dr. Wu Xue from the Institute of Atmospheric Physics (IAP) at the Chinese Academy of Sciences, highlights the important role of gravity waves generated by deep convection.

A review paper led by researchers from the University of St Andrews highlights the transformative potential in the use of radar in polar research to predict future sea levels.

According to NOAA, the global average sea level has risen 8–9 inches (21–24 centimeters) since 1880. The rate at which the sea level is rising is increasing, threatening coastal cities and ecosystems around the world.

It may sound counterintuitive, but new research suggests that cleaning up air pollution could contribute to a weakening of the Atlantic Meridional Overturning Circulation (AMOC). This is the ocean current system that acts like a giant conveyor belt, moving warm surface water northward and cool deep water southward.

It was the hardest field trip they had ever been on, but the result was both surprising and exciting. After hiking 9 kilometers with a 400-meter elevation gain and carrying heavy backpacks through very rocky terrain, the researchers spent more than 24 hours in the field and returned with sediment samples from the lake Stuptjørna.

A new study of the largest dam removal project in United States history on the Klamath River in Oregon and California is offering new insight into a long-running water conflict by finding that farmers and conservation groups share priorities that may help guide decision-making on future river restoration projects. The work is published in the journal Society & Natural Resources.

Tidal wetlands are critical, yet vulnerable ecosystems. Tidal marshes, mangrove forests, and tidal flats support biodiversity, protect against flooding and storm surges, sequester carbon, and improve water quality. Due to human development and climate change, tidal wetland areas have been shrinking globally. A new study using 40 years of satellite data shows that this loss has been accelerating in the U.S. and that this acceleration is being increasingly driven by extreme weather events.

Across the western United States, wildfires are increasing in size and intensity. As the climate continues to warm, more extreme wildfires will reshape landscapes and pose a growing risk to human health and natural ecosystems throughout the West.

Ghost forests, the cemetery-like groupings of dead trees killed by saltwater intrusion, have become haunting symbols of sea level rise overtaking land along the Mid-Atlantic coast. But a new study published in Nature Sustainability, led by William & Mary's Batten School & VIMS, points to even more dramatic land losses in the region's coastal farmlands, where the rate of marsh encroachment is happening nearly twice as fast.

Researchers at National Taiwan University and partner institutions have uncovered new evidence that Antarctic Intermediate Water (AAIW)—a distinct layer sitting 500–1,500 meters below the ocean surface—played a pivotal role in a major atmospheric carbon dioxide transition that occurred roughly 450,000 years ago.

Within the Canadian Shield, hydrogen gas is steadily building up naturally among some of the oldest rocks on Earth. Now, for the first time, geochemists at the University of Toronto and the University of Ottawa have measured its presence, mapped its concentration and tracked its long-term accumulation, shedding new light on this source of natural, or white, hydrogen.

Densely populated coastal regions in many parts of the world are particularly vulnerable to flooding. The sinking of land masses exacerbates the impacts of rising sea levels in these areas, according to a study by researchers from the Technical University of Munich (TUM) and Tulane University.

Researchers say accurately predicting Antarctica's impact on global sea levels is an urgent priority that can be achieved by analyzing the DNA of tiny land animals, pinpointing the continent's icy past to paint a clearer picture of the future.

Hydrogen gas formed by natural processes in the subsurface of mountain ranges could represent a promising source of clean energy. A new international study led by Unil and GFZ shows that erosion plays a key and complex role in the formation and accumulation of this natural resource. The research confirms that the Pyrenees and the Alps could constitute key targets for natural hydrogen exploration.

As climate change increases the risk of flooding worldwide, understanding how floods form has never been more important. However, the science behind flooding is notoriously difficult to grasp, involving interactions among atmospheric, terrestrial, and human systems. Creating educational tools that simplify these processes without losing their essential scientific meaning has remained a major challenge.

Tropical forests, often described as the lungs of the planet, may be edging closer to a dangerous threshold as droughts become more frequent and widespread across the world's humid tropics. New research suggests these ecosystems are increasingly struggling to recover from prolonged dry conditions, raising concerns that some forests could eventually shift from absorbing carbon dioxide to releasing it back into the atmosphere.

For years, scientists have warned that melting Antarctic ice could push sea levels dangerously higher by the end of this century. But a new study led by University of Maryland scientist Madeleine Youngs suggests those warnings may still be too conservative because they leave out a crucial factor: the ocean's own complex circulatory system.

As tropical cyclones (TCs) are among the most destructive natural hazards worldwide, understanding how TCs change under climate warming is of critical importance. While substantial progress has been made in projecting changes in TC intensity and precipitation, much less is known about how their vertical structure will respond to a warmer climate.

Earthquakes can visibly and permanently crack the ground apart in dramatic and unpredictable surface fault rupture, but new research led by University of Michigan Engineering revealed that soil density strongly influences how and where they occur. The paper is published in the Journal of Geotechnical and Geoenvironmental Engineering.