Phys.org: Earth science

Prediction is the goal and test of all science, one might argue. Meteorologists have been curious about the inherent limits of weather forecasting ever since the dawn of numerical weather prediction in the late 1950s.

Every monsoon, India's rivers turn brown. To most of us, that color simply means muddy water. But hidden within it is the material that builds fertile floodplains, creates river islands, nourishes deltas and even shapes coastlines: sediment.

A study led by Professor Jimmy Jiujiu Jiao from the Department of Earth and Planetary Sciences at The University of Hong Kong (HKU) and Professor Meng Li from Shenzhen University has identified microbial fermentation as the likely main pathway for ammonium production in sediments beneath the Pearl River Delta, helping to explain the region's exceptionally high natural groundwater ammonium levels.

El Niños and La Niñas are the third-most dominant influences on Earth's climate, after the sun and the greenhouse effect. But they haven't been easy to decipher or to predict in terms of when they will happen and what exact effects they will have on the global climate.

Roughly 2.5–2 billion years ago, Earth's surface experienced the biggest chemical change in its history when oxygen became abundant in the atmosphere, eventually leading to the evolution of complex life forms such as plants and animals that emerged half a billion years ago.

This summer, millions of people across the country have been digging out sunscreen to protect themselves from a record-breaking series of heat waves.

How much ice is stored in the world's glaciers? And where exactly is it located? A new study led by Ca' Foscari University of Venice, in collaboration with the Institute of Polar Sciences of the National Research Council of Italy (CNR-ISP), provides an updated global map of glacier ice volume.

The initiation of rain in clouds without ice remains one of the largest unsolved mysteries in atmospheric science.

Zooming from her office, Michigan State University researcher Kelly Kapsar showed satellite images from across the United States. In some, different colors revealed the precise heights of the forested ridges in the Sierra Nevada or the craggy peaks of the Rockies and the valleys between them. Others showed the pine flatwoods of southern Florida or the smooth, rolling grasslands of the Kansas prairie.

Throughout the 18th and 19th centuries, Europe's cartographers traded on their reputation for accuracy and detail at a time of huge societal change. But as demand grew for increasingly detailed maps of the world to support industrialization at home and colonization overseas, they didn't always get it right.

Stanford researchers have shown that instruments primarily used to understand earthquakes can capture key details about hurricanes, helping meteorologists better predict how storms will evolve and intensify.

The Arctic is warming at an accelerating pace. As permafrost thaws across vast areas and wildfires become more frequent, large amounts of methane (CH4) are being released. Together, these changes are reshaping the region's greenhouse gas emissions and further intensifying climate change.

The images of the major forest fires in Spain and France, with fire clouds near Bordeaux, have shocked many people. There have been numerous reports of the formation of a pyrocumulonimbus cloud—a fire-driven thundercloud—and the possible transport of smoke particles to Central Europe.

During the most recent ice age, much of North America disappeared beneath ice sheets several kilometers thick. These frozen giants covered most of present-day Canada and parts of the northern United States, while smaller ones spread across northern Europe.

Typhoons pose significant threats, with sudden, dangerous waves that endanger ships, offshore platforms and coastal infrastructure in the northwest Pacific Ocean. Current typhoon forecasting methods sometimes underestimate the largest waves during typhoons, but researchers in China have designed a new model that may offer improvements. Their new study, published in Ocean Engineering, describes how the model combines physics guidance with data-driven learning to improve typhoon forecasting.

Storm conditions capable of causing major coastal erosion at New Jersey's North Beach on Sandy Hook are occurring about twice as often as they did in 1979, according to Rutgers researchers. The finding offers new evidence that storm impacts are becoming more frequent along the Mid-Atlantic coast.

Fires in the Arctic are not solely a regional issue, as shown by the hazy skies in Switzerland last summer despite otherwise sunny weather. Smoke from major fires in northern Canada crossed the Atlantic and reached Europe. Until now, large-scale studies of Arctic tundra fires have focused primarily on rising temperatures and drought as the main drivers. The role of human activity has received much less attention, even as industrial development, settlements, roads and other infrastructure expand rapidly in parts of the Arctic, particularly in connection with extractive industries such as oil and gas production and mining.

Can a crack be supersonic? Can the fracture that triggers an avalanche propagate faster than the limiting velocity predicted by classical fracture mechanics? The question remains the subject of debate within the scientific community. While some numerical and experimental studies suggest that avalanche cracks may propagate at supersonic speeds, others offer a different interpretation.

The effects of climate change extend far beyond rising temperatures. As forests and other vegetation respond to a warming world, they also change the amount of biogenic emissions released into the atmosphere, influencing the formation of ozone (O3) and fine particulate pollution. Yet many atmospheric chemistry models still estimate these emissions using vegetation data from 2003, despite major ecological changes across East Asia over the past two decades.

Scientists have uncovered a previously unknown natural process that dramatically increases the number of cloud-forming particles in the Arctic atmosphere—potentially altering cloud cover, sunlight reflection and future climate change.