Taxonomy term

november 2015

Geomedia: Gifts: Holiday Gift Guide

Science is definitely the new chic, so we’ve tracked down the latest and greatest science accessories and furnishings to help you find the perfect gift for home or office. From agate nightlights to fun science jewelry, this list is sure to have something your science lover will enjoy. Plus, we have some suggestions for great presents for the budding young scientists in your life.
28 Nov 2015

No laughing matter: Ocean nitrous oxide emissions greater than thought

Nitrous oxide is a potent greenhouse gas and, since the banning of chlorofluorocarbons in 1987, it has become the main driver of ozone loss from the stratosphere. Most atmospheric nitrous oxide is emitted from agricultural land and soils, but roughly a third is thought to come from the ocean. However, marine sources and sinks of the gas are not well understood. 
27 Nov 2015

Solar flare calibration reveals past patterns of volcanism and cooling

When Mount Pinatubo erupted in the Philippines in 1991, it sent a cloud of ash and sulfuric acid into the atmosphere that blocked incoming solar radiation and caused global temperatures to drop 0.5 degrees Celsius for three years. Quantifying such effects of prehistoric volcanic eruptions on climate, however, has long proved difficult due to inconsistencies in the proxies used to reconstruct atmospheric and temperature fluctuations. In a new study, scientists have used markers left by an unusual solar flare event to align ice-core and tree-ring records, enabling a more accurate accounting of the effects of volcanic eruptions in recent millennia.
25 Nov 2015

Enceladus' extremely alkaline underground ocean

Saturn’s moon Enceladus is home to a vast underground ocean that erupts to the surface at the moon’s south pole in a giant plume of gas, ice and dust. Scientists studying observational data of this plume collected by the Cassini spacecraft, which has been orbiting Saturn since 2004, have recently learned more about the chemistry of Enceladus’ hidden ocean. 
24 Nov 2015

Butchery or trampling? Controversy marks ancient animal bones

At some point in early human evolution, our ancestors began regularly hunting, butchering and consuming meat from large game, a protein- and fat-rich change in diet that may have helped fuel the development of a larger and more complex brain. When exactly this change took place has long been a matter of debate. Stone tools from 2.6 million years ago have offered the most solid evidence to date. But the discovery several years ago of a pair of 3.4-million-year-old animal bones in Dikika, Ethiopia, that appear to show cut marks indicative of butchery could push the date back significantly. Some researchers think the bones were marked by incidental trampling, however, not by early humans. 
22 Nov 2015

Due diligence in river incision data

As great equalizers of topography, rivers and streams whittle down landscapes by alternately scouring away broad flat swaths of sediment and rock, and incising deeply through them. If a landscape — a mountain range, for example — is being uplifted by tectonic forces, this whittling occurs even faster. River incision rates in particular are thus often used to infer past rates of rock uplift. But determining incision rates themselves is not clear-cut. In a new study in Geology, scientists look at one complicating factor in such calculations, what the authors call the “unappreciated effects of streambed elevation variability” on measuring river incision rates.
21 Nov 2015

Warty algae-like sheets survived Snowball Earth events

Between about 730 million and 635 million years ago, during the Cryogenian Period of the Late Proterozoic, Earth is thought to have been almost completely covered in ice twice, events that scientists have termed “Snowball Earth” glaciations. The first global glaciation, the Sturtian, lasted from 730 million to 700 million years ago, and the second, the Marinoan, lasted from 660 million to 635 million years ago. Both glaciations likely put severe limitations on the ability of life — predominately microorganisms — to thrive. 
19 Nov 2015

Comment: Pipe Dreams: What have we learned from the Volkswagen Clean-Diesel scandal?

It came to light this fall that Volkswagen had emplaced so-called defeat devices in millions of clean-diesel cars, thus allowing the cars to pass emissions tests but still drive the way consumers wanted. Many questions remain, but the scandal has already provided important lessons about consumer behavior, markets and the temptation to cheat in this new era of environmental anxiety.

18 Nov 2015

Geomedia: Television: 'NOVA: Making North America' Is Flashy, But Fails on Storytelling

A new three-hour-long documentary, “NOVA: Making North America,” airing in November, purports to tell the geological, biological and anthropological story of North America. Unfortunately, it falls short on many counts.

17 Nov 2015

Buckyballs behind Milky Way mystery

For almost a century, astronomers have observed gaps in the broad spectrum of light reaching Earth from other stars in the Milky Way galaxy. These gaps, called diffuse interstellar bands (DIBs), arise when dust and molecules in interstellar space absorb specific wavelengths of light, thus darkening those bands of light from view. Although hundreds of distinct DIBs have been recognized, scientists have only been able to hypothesize as to the identity of the molecules responsible, until now. In a new study published in Nature, scientists say they have “positively identified” one of the interstellar light-absorbers: nanometer-wide carbon cages named buckminsterfullerene, or “buckyballs.”
17 Nov 2015