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Oldest human remains outside Africa found in Israel

The recent discovery of a jawbone belonging to Homo sapiens, and associated stone tools, in Israel may push back the timing of the earliest human migration out of Africa by as much as 50,000 years.

28 May 2018

From silver to snow: Full cloud seeding cycle observed

Cloud seeding — adding particles to clouds to modify precipitation patterns — has been suggested as a way to trigger rain and snowfall, which could help sustain mountain snowpack and water supplies across the western U.S. However, it has been challenging to demonstrate the technique’s effectiveness and efficiency, in part because direct observations of the full chain of events involved in cloud seeding have been lacking.

25 May 2018

A new look at Cheddar Man

In 1903, a skeleton was found in a limestone cave in Cheddar Gorge, near Somerset, England. Radiocarbon dating in the 1970s revealed the remains to be more than 10,000 years old, making it the oldest near-complete human skeleton found in Britain. Now, as yet unpublished research suggests Cheddar Man’s genome reveals a surprisingly different appearance for the Mesolithic man from what’s long been thought, according to researchers who analyzed DNA from the skeleton.

23 May 2018

Lava shaped Lake Tahoe

With its preternaturally clear blue waters, Lake Tahoe is tranquil today, but the deep lake straddling the border of California and Nevada was once the site of repeated lava flows. In a new study, researchers used radiometric argon dating to describe how episodes of volcanism created the landscape around the largest alpine lake in North America.

21 May 2018

Swelling clay slows landslides

Rainfall can trigger landslides, and it can also cause slow-moving slides to speed up. But researchers have observed that rain also appears to cause landslides composed of clay-rich material to take longer to start moving, and to move slower than expected.

17 May 2018

When more humidity means less water

Scientists have long assumed that temperature is the main control on melting of winter snowpacks across the mountainous western United States. In a recent study, however, scientists suggest that regional humidity may have a larger impact than temperature.

16 May 2018

El Nino "flavors" affect California rainfall

Twenty years ago, the 1997–98 El Niño surpassed the 1982–83 event to become the strongest El Niño ever recorded, contributing to famine and drought in Southeast Asia, devastating floods in Southern California, and other natural disasters. By many metrics, the 2015–16 El Niño bested both to claim the title of the strongest El Niño on record. This most recent event, nicknamed the “Godzilla El Niño,” did contribute to extreme weather in parts of the world, including disastrous fires in Indonesia and the longest, global coral-bleaching event on record. However, it did not have the anticipated effect on California, which, at the time, was in the midst of a severe multi-year drought. In a recent study, researchers suggest the 2015–16 El Niño was the wrong “flavor” to bring heavy precipitation to the state.

13 May 2018

Rising waters sink seafloors

Predicting how much the ocean surface will rise in the coming years requires complicated, global-scale bookkeeping of the many factors that affect sea levels. In a new study, scientists have, for the first time, quantified the role of ocean-bottom deformation — the gradual deepening of ocean basins under the weight of more water — in both global and regional sea-level rise, an effort that may help produce more accurate sea-level projections.

13 May 2018

Geologic evidence confirms existence of 405,000-year Milankovitch cycle

Earth’s rock record preserves evidence of numerous natural processes, from evolution and extinction to catastrophes and climate change, and sometimes even planetary configurations. In a new study, a well-preserved sequence of Triassic lake sediments bearing evidence of cyclical patterns of climate change in the Newark Basin confirms the existence of a Milankovitch cycle — a periodic change in the shape of Earth’s orbit caused by, in this case, Earth’s gravitational interactions with Jupiter and Venus. The finding can be used to precisely date other events in the geological record, and inform climate and astronomical models.

11 May 2018

Flightless dino had bright, rainbow-colored feathers

In recent years, many dinosaurs have gotten a fabulously feathered makeover, but for the most part, scientists still aren’t sure what colors the animals were. A new discovery of a finely preserved feathered dinosaur fossil in China suggests that some dinosaurs were as brightly colored as modern-day hummingbirds.

10 May 2018

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