Science Daily

About 466 million years ago, long before the age of the dinosaurs, the Earth froze. The seas began to ice over at the Earth's poles, and new species evolved with the new temperatures. The cause of this ice age was a mystery, until now: a new study argues that the ice age was caused by global cooling, triggered by extra dust in the atmosphere from a giant asteroid collision in outer space.

Thick, impenetrable ice slabs are expanding rapidly on the interior of Greenland's ice sheet, where the ice is normally porous and able to reabsorb meltwater. These slabs are instead sending meltwater spilling into the ocean, according to a new assessment, threatening to increase the country's contribution to sea level rise by as much as 2.9 inches by 2100.

A new article presents 19 high-coverage penguin genome sequences. Adding this to the two previously published penguin genomes, there are now genome sequences available for all living penguin species. Here, the Penguin Genome Consortium, made up of researchers from 10 countries, has produced an unparalleled amount of information that covers an entire biological order. Research from evolution, the impact of human activities impact, and environmental changes, will benefit from this work.

A key question for climate scientists in recent years has been whether the Atlantic Ocean's main circulation system is slowing down, a development that could have dramatic consequences for Europe and other parts of the Atlantic rim. But a new study suggests help may be on the way from an unexpected source -- the Indian Ocean.

The sea-ice extent in the Arctic is nearing its annual minimum at the end of the melt season in September. Only circa 3.9 million square kilometers of the Arctic Ocean are covered by sea ice any more, according to researchers.

Life on Earth is amazingly diverse, and exhibits striking geographical global patterns in biodiversity. A pair of companion papers reveal that mountain regions -- especially those in the tropics -- are hotspots of extraordinary and baffling richness. Although mountain regions cover only 25% of Earth's land area, they are home to more than 85% of the world's species of amphibians, birds, and mammals, and many of these are found only in mountains.

By looking into fossil teeth from almost 2 million years old rhinos, researchers have launched a new molecular method for studying the evolutionary history of fossil species dating back millions of years.

The Navajo Sandstone is known for its beautiful red and tan crossbedded sandstones that grace many of the national parks and monuments in the southwest USA. The sands were deposited in dunes within the largest known sand sea (erg) in Earth's history during the Early Jurassic. These deposits show a record of desertification -- the process by which fertile lands become desert. How did this landscape lose its water bodies, vegetation, and animals?

Newly available archival film has revealed the eastern ice shelf of Thwaites Glacier in Antarctica is melting faster than previous estimates, suggesting the shelf may collapse sooner than expected.

Scientists, studying evidence preserved in speleothems in a coastal cave, illustrate that more than three million years ago -- a time in which the Earth was two to three degrees Celsius warmer than the pre-industrial era -- sea level was as much as 16 meters higher than the present day.

Arctic sea-ice has decreased rapidly during the last decades in concert with substantial global surface warming. Both have happened much faster than predicted by climate models, and observed Arctic warming is much stronger than the global average. Projections suggest that Arctic summer sea-ice may virtually disappear within the course of the next fifty or even thirty years.

Variations in the depth of snow cover in the Arctic region from late winter to spring determines the summer temperature pattern in Eurasia, according to new research. In particular, deeper-than-usual snow cover in Western Russia enhanced the likelihood of summer heat waves in Europe and Northeast Asia in recent years.

Researchers have developed a way to remove ice and frost from surfaces extremely efficiently, using less than 1% of the energy and less than 0.01% of the time needed for traditional defrosting methods. Instead of conventional defrosting, which melts all the ice or frost from the top layer down, the researchers established a technique that melts the ice where the surface and the ice meet, so the ice can simply slide off.

Stone tools and other artifacts unearthed from an archeological dig at the Cooper's Ferry site in western Idaho suggest that people lived in the area 16,000 years ago, more than a thousand years earlier than scientists previously thought.

Scientists used geologic records from deep-sea drill cores to extend the astronomical time scale beyond 50 million years, by about 8 million years. Using their new chronology, they provide a new age for the Paleocene-Eocene boundary (56.01 Ma) with a small margin of error (0.1%).

When climates change, plants and animals often are forced to colonize new areas -- or possibly go extinct. Because the climate is currently changing, biologists are keenly interested in predicting how climate-induced migrations influence organisms over time.

New research finds Arctic Ocean currents and storms are moving bacteria from ocean algae blooms into the atmosphere where the particles help clouds form. These particles, which are biological in origin, can affect weather patterns throughout the world, according to the new study.

New research compares the growth rates between nearshore and offshore corals in the Belize Mesoamerican Barrier Reef System, the world's second-largest reef system. While nearshore corals have historically grown faster than those offshore, over the past decade there was a decline in the growth rates of two types of nearshore corals, while offshore coral growth rates in the same reef system stayed the same.

The oldest parasite DNA ever recorded has been found in the ancient, desiccated feces of a puma.

Glacier-fed rivers in northern Canada may be consuming significant amounts of carbon dioxide from the atmosphere, according to new research.