The state of the Atlantic Meridional Overturning Circulation (AMOC) has been a hot topic among climate scientists in recent years. The AMOC is crucial for climate regulation because it pulls warm surface water from the tropics north and sends colder, deeper water south, redistributing large amounts of heat, helping to sustain marine ecosystems and keeping global weather patterns steady. However, most standard AMOC-focused climate models may be missing an important piece of the puzzle—they don't include the growing pulse of freshwater from Greenland ice melt, which could further disrupt the AMOC.
Tropical moist forests account for 70% of global living biomass. Deforestation and degradation—that is, the partial damage to tree stands—as well as the subsequent regeneration of forests therefore play a pivotal role in the global carbon cycle. While the effects of large-scale tropical deforestation are well understood, the impacts of forest degradation have remained highly uncertain until now.
The Southern Ocean has long stood out as an oddity in the global climate system. While most of the planet's surface oceans have warmed in response to rising greenhouse gases, waters circling Antarctica showed an unexpected tendency to cool during the late 20th and early 21st centuries. This cooling coincided with a period when Antarctic sea ice briefly expanded before its more recent decline, adding to the mystery.
Every summer, communities across northern Australia brace for the tropical cyclone season. Tropical cyclones draw their power from the warm seas, extracting heat and moisture from ocean water.
Europe's summer heat wave has exposed tens of millions of people to temperatures above 35°C, broken records and claimed hundreds of lives. Early climate attribution studies suggest Europe's event would have been "virtually impossible" just 50 years ago without human-caused climate change.
The Congo River is the second-largest river in the world, releasing an average of 40,000 cubic meters of water per second into the Atlantic Ocean. This huge discharge rate creates a large plume of fresh water that fans out 800 kilometers (500 miles) offshore.
SummaryGravity inversion is an essential technique for recovering subsurface density variations. Constructing stratigraphic models from gravitational observations, however, remains challenging because gravity data provide limited vertical resolution and the inverse problem is strongly non-unique. To address these limitations, we develop a Bayesian geometry-based gravity inversion framework aimed specifically for stratigraphic reconstruction. Stratigraphic interfaces are parameterized using a Fourier series, which provides a compact set of variables, enables a controllable representation of layer geometry, and improves the vertical resolution of the recovered density model. Uncertainty in the inferred stratigraphy is quantified with Stein variational inference, yielding an ensemble approximation to the posterior distribution. The resulting posterior models reveal the confidence level and spatial variability of stratigraphic layers. The proposed method has been validated using two toy examples to illustrate the main concepts. Two synthetic lunar basin models, representing alternative interpretive hypotheses for upper-crustal layering, are further designed to evaluate algorithm performance. Finally, application to satellite gravity observations from the Orientale Basin demonstrates that the proposed framework can recover the basin’s large-scale tectonic structure.
When NASA's Cyclone Global Navigation Satellite System, or CYGNSS, launched into orbit in 2016, none of the University of Michigan Engineering researchers who developed the system expected it to transform earth science. They certainly had high hopes for the system's original mission to improve hurricane forecasting, but its ability to pick up reflected GPS signals also proved useful for much more.
Many of the boulders scattered across the Swiss landscape did not originate where they now stand. Instead, they were carried by ice nearly 24,000 years ago. For the first time, researchers at the University of Lausanne (UNIL) have reconstructed the journeys of these giant rocks across the entire Alpine region using a simulation. The model makes it possible to visualize the paths taken by millions of rocks that helped shape today's landscapes.
Prescribed fires are vital for reducing wildfire risk and sustaining forest biodiversity. But they also contribute significantly to air pollution and smoke exposure, according to new research from the University of Georgia. The issue is especially pertinent to the southeastern United States, where 60% of all prescribed fires in the country occur. More than 20% of the fine-particle pollution in the southeastern U.S. can be attributed to prescribed burns, the study found.
One seismometer is often not enough to reliably detect earthquakes or human activity such as underground nuclear tests. Rather, researchers combine readings from seismometers distributed across a small geographic area to gain confidence in their analysis. Artificial intelligence (AI) can combine readings from multiple sensors more effectively than classic technology, enabling more reliable detection of weak seismic signals, a new study by A. Köhler and colleagues shows.
Scientists have uncovered why Antarctica became engulfed by ice millions of years before the Arctic. The international research, published in Science, helps solve one of climate science's longest-standing puzzles: how a vast ice sheet could form when Earth was around 5°C warmer than today.
Nearly 660 kilometers (410 miles) beneath Earth's surface lies one of the planet's most important internal boundaries. Known as the 660-km seismic discontinuity, it separates the mantle transition zone from the lower mantle and plays a central role in controlling how heat and materials circulate through Earth's interior. This circulation helps drive mantle convection, plate tectonics, volcanic activity and the long-term evolution of the planet. Although scientists have generally attributed this boundary to the breakdown of the mineral ringwoodite into bridgmanite and ferropericlase, that explanation has struggled to account for the complex structures detected by seismic observations beneath subduction zones and mantle plumes.
If you have ever hiked in the high peaks of Colorado, the Wasatch Range in Utah or the Tetons in Wyoming, you've almost certainly seen a rock glacier, perhaps without even knowing it.
This image shows the sea surface temperature anomaly detected in the Mediterranean Sea on June 29, 2026, compared with the average for the period 1991–2020, with dark red indicating temperatures that exceed the average by up to 8°C (14.4°F).
Worsened drought stress, changing rainfall patterns, flowers and pollinators thrown out of sync: These only scratch the surface of the ways climate change challenges plant life. But warmer air and higher carbon dioxide levels can also fuel faster plant growth, limit plants' water loss and extend growing seasons—enough so, in some cases, to offset the paving over of green spaces in cities.
SummaryThicknesses and bulk Vp/Vs ratios of crustal layers (or Poisson’s ratio) are fundamental parameters for understanding continental structure, composition, and tectonic evolution. Traditional receiver function (RF) methods analyze P-to-S converted phases to estimate these parameters but face significant challenges in regions with low-velocity sedimentary layers, where sediment-related multiples contaminate deeper crustal signals and bias parameter estimates. We present a sequential RF-AC H-κ phase-weighted stacking method that jointly analyzes RFs and coda autocorrelations (ACs) to simultaneously constrain sedimentary and underlying crystalline crustal properties. Integration of AC data provides independent constraints on P- and S-wave reflection times, improving estimation robustness. Synthetic tests demonstrate that our method effectively suppresses sediment multiple interference and yields more reliable layer thickness and Vp/Vs ratio estimates than conventional RF-only approaches. We apply this method to four broadband stations in contrasting tectonic settings: the extensional Bohai Bay Basin and stable Tarim Basin, China. Results reveal 2.0 – 10.0 km thick sedimentary layers with Vp/Vs ratios decreasing from ~ 2.90 to 2.00 with depth, consistent with progressive compaction. Crustal thickness estimates show significant tectonic variability: 28.0 – 32.0 km in the extensional Bohai Bay Basin versus ~ 40 km in the stable Tarim Basin. Crystalline crustal Vp/Vs ratios of 1.66 – 1.73 at three stations indicate predominantly felsic composition, while a higher ratio (~ 1.80) in southwestern Tarim suggests more mafic materials. These findings agree with independent geophysical observations and geological constraints, demonstrating that this method provides a robust framework for constraining layered continental crust with thick sedimentary basins.
A research group led by Satoshi Ide from the University of Tokyo has demonstrated that classic earthquake generation theory does not hold in areas where the angle at which a tectonic plate dips under another is sufficiently low. The discovery explains why giant earthquakes can form in such areas, providing a theoretical basis to extend observation efforts to previously overlooked features. The findings are published in Science Advances.
Earthquakes still arrive without warning. That is the hard truth scientists have been forced to accept, despite a decade of advances in artificial intelligence, satellite monitoring and dense seismic networks.
Perfluorooctanoic acid (PFOA) is one of the per- and polyfluoroalkyl substances (PFAS), a class of substances within a broader universe of organofluorine compounds. PFOA has potential adverse effects on human health and environmental safety because of its toxicity and bioaccumulation. Its innate chemical stability, widespread use, and long-range transport result in PFOA's ubiquity in the global environment.
