Scientists have revealed that ancient bogs in the Southern Hemisphere hold clues to a major shift in Earth’s climate thousands of years ago.
Researchers looking at peatlands have discovered that sudden shifts in the Southern Westerly Winds 15,000 years ago triggered a massive growth of the swamps.
Geo-experts have never fully understood what caused the bogs to form across the Southern Hemisphere after the last Ice Age.
Using lasers as tweezers to understand cloud electrification might sound like science fiction, but at the Institute of Science and Technology Austria (ISTA) it is a reality. By trapping and charging micron-sized particles with lasers, researchers can now observe their charging and discharging dynamics over time.
This method, published in Physical Review Letters, could provide key insights into what sparks lightning.
Aerosols are liquid or solid particles that float in the air. They are all around us. Some are large and visible, such as pollen in spring, while others, such as viruses that spread during flu season, cannot be detected by the naked eye. Some we can even taste, like the airborne salt crystals we breathe in at the seaside.
Imagine the catastrophic winds of a category 5 hurricane. Now, imagine even faster winds of more than 100 meters per second, encircling the planet and whipping clouds across the sky, with no end in sight. This scenario would be astonishing on Earth, but it’s business as usual on Venus, where the atmosphere at cloud level rotates about 60 times faster than the planet itself—a phenomenon known as superrotation. In contrast, Earth’s cloud-level atmosphere rotates at about the same speed as the planet’s surface.
Prior research has explored the mechanisms driving atmospheric superrotation on Venus, but the details remain murky. New evidence from Lai and team suggests that a once-daily atmospheric tidal cycle, fueled by heat from the sun, contributes much more to the planet’s extreme winds than previously thought. The study is published in the journal AGU Advances.
Rapid atmospheric rotation often occurs on rocky planets that, like Venus, are located relatively close to their stars and rotate very slowly. On Venus, one full rotation takes 243 Earth days. Meanwhile, the atmosphere races around the planet in a mere 4 Earth days.
Researchers at the University of California, Irvine and NASA’s Jet Propulsion Laboratory have identified stormlike circulation patterns beneath the Antarctic ice shelves that are causing aggressive melting, with major implications for global sea level rise projections.
In a paper published recently in Nature Geoscience, the scientists say their study is the first to examine ocean-induced ice shelf melting events from a weather timescale of just days versus seasonal or annual timeframes. This enabled them to match “ocean storm” activity with intense ice melt at Thwaites Glacier and Pine Island Glacier in the climate change-threatened Amundsen Sea Embayment in West Antarctica.
The research team relied on climate simulation modeling and moored observation tools to gain 200-meter-resolution pictures of submesoscale ocean features between 1 and 10 kilometers across, tiny in the context of the vast ocean and huge slabs of floating ice in Antarctica.
Researchers have successfully performed the world’s first Milky Way simulation that accurately represents more than 100 billion individual stars over the course of 10 thousand years. This feat was accomplished by combining artificial intelligence (AI) with numerical simulations. Not only does the simulation represent 100 times more individual stars than previous state-of-the-art models, but it was produced more than 100 times faster.
Published in Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis, the study represents a breakthrough at the intersection of astrophysics, high-performance computing, and AI. Beyond astrophysics, this new methodology can be used to model other phenomena such as climate change and weather patterns.
A newly discovered, remarkably well-preserved impact crater is shedding fresh light on how extraterrestrial bodies collide with Earth.
In the journal Matter and Radiation at Extremes, researchers from Shanghai and Guangzhou, China, report the discovery of the Jinlin crater: an impact structure nestled on a hillside and preserved within a thick granite weathering crust.
Located in Zhaoqing, Guangdong Province, China, it is one of only about 200 identified craters worldwide and is very young in geological years. Based on measurements of nearby soil erosion, it likely formed during the early-to-mid Holocene—our current geological epoch, which began at the end of the last ice age about 11,700 years ago.
Weather forecasting is notoriously wonky — climate modeling even more so. But their increasing ability to predict what the natural world will throw at us humans is largely thanks to two things — better models and increased computing power.
Now, a new paper from researchers led by Daniel Klocke of the Max Planck Institute in Germany describes what some in the climate modeling community have described as the “holy grail” of their field — an almost kilometer-scale resolution model that combines weather forecasting with climate modeling.
Technically the scale of the new model isn’t quite 1 sq km per modeled patch — it’s 1.25 kilometers.
The way clusters of differently sized water droplet populations are distributed within clouds affects larger-scale cloud properties, such as how light is scattered and how quickly precipitation forms. Studying and simulating cloud droplet microphysical structure is difficult. But recent field observations have provided crucial, centimeter-scale data on cloud droplet size distributions in stratocumulus clouds, giving researchers an opportunity to better match their models to reality.
The simulations of characteristic droplet size distributions that those models are providing are likely too uniform, say Nithin Allwayin and colleagues. This muddled microphysical structure could be leading cloud simulations, and the climate models that use them, astray. Their paper is published in the journal Geophysical Research Letters.
The authors compare the new observed data on cloud microphysical structure with results from large-eddy simulations (LES) of stratocumulus clouds. At convective scales, the model showed intriguing correlations between droplet cluster characteristics and overall cloud physics. For example, regions of the clouds dominated by drizzle tended to have larger drops but not necessarily more total water content, and the updraft regions of clouds tended to have smaller drops and a narrower distribution of droplet size.
A new study in Environmental Research Letters reports that cooling the planet by injecting sulfur dioxide into the stratosphere, a proposed climate intervention technique, could reduce the nutritional value of the world’s crops.
Scientists at Rutgers University used global climate and crop models to estimate how stratospheric aerosol intervention (SAI), one type of solar geoengineering, would impact the protein level of the world’s four major food crops: maize, rice, wheat, and soybeans. The SAI approach, inspired by volcanic eruptions, would involve releasing sulfur dioxide into the stratosphere. This gas would transform into sulfuric acid particles, forming a persistent cloud in the upper atmosphere that reflects a small part of the sun’s radiation, thereby cooling Earth.
While these cereal crops are primarily sources of carbohydrates, they also provide a substantial share of dietary protein for large portions of the global population. Model simulations suggested that increased CO2 concentrations tended to reduce the protein content of all four crops, while increased temperatures tended to increase the protein content of crops. Because SAI would stop temperatures from increasing, the CO2 effect would not be countered by warming, and protein would decrease relative to a warmer world without SAI.