General Meteorology and Earth Science Thread

Breakup of ancient supercontinent Pangea hints at future fate of Atlantic Ocean: "Pangea, the supercontinent that contained most of the Earth's landmass until about 180 million years ago, endured an apocalyptic undoing during the Jurassic period, when the Atlantic Ocean opened up. This is well understood. But what is less clear is how Pangea came into being in the first place.

Earth and atmospheric sciences professor John Waldron in the University of Alberta's Faculty of Science, along with three colleagues in Atlantic Canada and the United Kingdom, recently described a new model for the events that led to the closing of ancient oceans and the formation of Pangea. The scientists outline their findings in a paper published in the journal Geology.

According to Waldron and his fellow authors, the answers may be found in the best known of the ancient oceans, Iapetus, which lay between the ancient core of North America and parts of what are now Europe, Africa and South America."

Most of Earth's carbon may be hidden in the planet's inner core, new model suggests: "As much as two-thirds of Earth's carbon may be hidden in the inner core, making it the planet's largest carbon reservoir, according to a new model that even its backers acknowledge is 'provocative and speculative.'

In a paper scheduled for online publication in the Proceedings of the National Academy of Sciences this week, University of Michigan researchers and their colleagues suggest that iron carbide, Fe7C3, provides a good match for the density and sound velocities of Earth's inner core under the relevant conditions."

Localized climate change contributed to ancient southwest depopulation: "The role of localized climate change in one of the great mysteries of North American archaeology — the depopulation of southwest Colorado by ancestral Pueblo people in the late 1200s — has been detailed by researchers. In the process of their study, investigators address one of the mysteries of modern-day climate change: How will humans react?"

Geophysicists challenge traditional theory underlying the origin of mid-plate volcanoes: "A long-held assumption about the Earth is discussed in today's edition of Science, as Don L. Anderson, an emeritus professor with the Seismological Laboratory of the California Institute of Technology, and Scott King, a professor of geophysics in the College of Science at Virginia Tech, look at how a layer beneath the Earth's crust may be responsible for volcanic eruptions.

The discovery challenges conventional thought that volcanoes are caused when plates that make up the planet's crust shift and release heat.

Instead of coming from deep within the interior of the planet, the responsibility is closer to the surface, about 80 kilometers to 200 kilometers deep—a layer above the Earth's mantle, known as the as the asthenosphere."

Oil-dwelling bacteria are social creatures in Earth's deep biosphere, new study shows: "Oil reservoirs are scattered deep inside the Earth like far-flung islands in the ocean, so their inhabitants might be expected to be very different, but a new study led by Dartmouth College and University of Oslo researchers shows these underground microbes are social creatures that have exchanged genes for eons.

The study, which was led by researchers at Dartmouth College and the University of Oslo, appears in the ISME Journal.

The findings shed new light on the 'deep biosphere,' or the vast subterranean realm whose single-celled residents are estimated to be roughly equal in number and diversity to all the microbes inhabiting the surface's land, water and air. Deep microbial research may also help scientists to better understand life's early evolution on Earth and aid the search for life on Mars and other planets."

Scientists observe the Earth grow a new layer under an Icelandic volcano: "New research into an Icelandic eruption has shed light on how the Earth's crust forms, according to a paper published today in Nature.

When the Bárðarbunga volcano, which is buried beneath Iceland's Vatnajökull ice cap, reawakened in August 2014, scientists had a rare opportunity to monitor how the magma flowed through cracks in the rock away from the volcano. The molten rock forms vertical sheet-like features known as dykes, which force the surrounding rock apart.

Study co-author Professor Andy Hooper from the Centre for Observation and Modelling of Earthquakes, volcanoes and Tectonics (COMET) at the University of Leeds explained: 'New crust forms where two tectonic plates are moving away from each other. Mostly this happens beneath the oceans, where it is difficult to observe.'"

Fermi brings deeper focus to thunderstorm gamma-rays: "Each day, thunderstorms around the world produce about a thousand quick bursts of gamma rays, some of the highest-energy light naturally found on Earth. By merging records of events seen by NASA's Fermi Gamma-ray Space Telescope with data from ground-based radar and lightning detectors, scientists have completed the most detailed analysis to date of the types of thunderstorms involved.

'Remarkably, we have found that any thunderstorm can produce gamma rays, even those that appear to be so weak a meteorologist wouldn't look twice at them,' said Themis Chronis, who led the research at the University of Alabama in Huntsville (UAH).

The outbursts, called terrestrial gamma-ray flashes (TGFs), were discovered in 1992 by NASA's Compton Gamma-Ray Observatory, which operated until 2000. TGFs occur unpredictably and fleetingly, with durations less than a thousandth of a second, and remain poorly understood."

Ancient, hydrogen-rich waters discovered deep underground at locations around the world: "A team of scientists, led by the University of Toronto's Barbara Sherwood Lollar, has mapped the location of hydrogen-rich waters found trapped kilometres beneath Earth's surface in rock fractures in Canada, South Africa and Scandinavia.

Common in Precambrian Shield rocks - the oldest rocks on Earth - the ancient waters have a chemistry similar to that found near deep sea vents, suggesting these waters can support microbes living in isolation from the surface.

The study, to be published in Nature on December 18, includes data from 19 different mine sites that were explored by Sherwood Lollar, a geoscientist at U of T's Department of Earth Sciences, U of T senior research associate Georges Lacrampe-Couloume, and colleagues at Oxford and Princeton universities."

Strange rock containing 30,000 diamonds baffles scientists

Ancient Earth may have made its own water: Rock circulating in mantle feeds world's oceans even today, evidence suggests: "In a finding that meshes well with recent discoveries from the Rosetta mission, researchers have discovered a geochemical pathway by which Earth makes it own water through plate tectonics. This finding extends the planet's water cycle to billions of years — and suggests that enough water is buried in the deep earth right now to fill the Pacific Ocean."

What the 'fecal prints' of microbes can tell us about Earth's evolution: "The distinctive "fecal prints" of microbes potentially provide a record of how Earth and life have co-evolved over the past 3.5 billion years as the planet's temperature, oxygen levels, and greenhouse gases have changed. But, despite more than 60 years of study, it has proved difficult, until now, to "read" much of the information contained in this record. Research from McGill University and Israel's Weizmann Institute of Science, recently published in the Proceedings of the National Academy of Sciences (PNAS), sheds light on the mysterious digestive processes of microbes, opening the way towards a better understanding of how life and the planet have changed over time."

Ionic liquids open door to better rare-earth materials processing: "U.S. Department of Energy's Ames Laboratory and Critical Materials Institute materials chemist Anja Mudring is harnessing the promising qualities of ionic liquids, salts in a liquid state, to optimize processes for critical materials.

'Ionic liquids have a lot of useful qualities, but most useful for materials processing is that ionic liquids are made up of two parts: the cation and the anion. We can play around with the chemical identities of each of those components and that opens the doors to huge amount of options,' says Mudring. 'That means we can really engineer ionic liquids with specific functions in mind.'

One such function is improving the rare-earth separation process, either for extracting rare earths from ore or recycling rare earths from discarded magnets."

The city of Irving, Texas is calling in seismologists from Southern Methodist University to figure out why earthquakes keep happening under the site of the former Texas Stadium, the old home of the Dallas Cowboys.

Fracking confirmed as cause of rare 'felt' earthquake in Ohio: "A new study links the March 2014 earthquakes in Poland Township, Ohio to hydraulic fracturing that activated a previously unknown fault. The induced seismic sequence included a rare felt earthquake of magnitude 3.0, according to research published online by the Bulletin of the Seismological Society of America (BSSA)."

Epic survey finds regional patterns of soot and dirt on North American snow: "Snow is not as white as it looks. Mixed in with the reflective flakes are tiny, dark particles of pollution. University of Washington scientists recently published the first large-scale survey of impurities in North American snow to see whether they might absorb enough sunlight to speed melt rates and influence climate.

The results, published in the Journal of Geophysical Research, show that North American snow away from cities is similar to Arctic snow in many places, with more pollution in the U.S. Great Plains. They also show that agricultural practices, not just smokestacks and tailpipes, may have a big impact on snow purity."

edited 9th Jan '15 1:39:07 PM by rmctagg09

Small volcanic eruptions partly explain 'warming hiatus': "The 'warming hiatus' that has occurred over the last 15 years has been partly caused by small volcanic eruptions.

Scientists have long known that volcanoes cool the atmosphere because of the sulfur dioxide that is expelled during eruptions. Droplets of sulfuric acid that form when the gas combines with oxygen in the upper atmosphere can persist for many months, reflecting sunlight away from Earth and lowering temperatures at the surface and in the lower atmosphere.

Previous research suggested that early 21st century eruptions might explain up to a third of the recent 'warming hiatus.'"

On a tropical island, fossils reveal the past—and possible future—of polar ice: "The balmy islands of Seychelles couldn't feel farther from Antarctica, but their fossil corals could reveal much about the fate of polar ice sheets.

About 125,000 years ago, the average global temperature was only slightly warmer, but sea levels rose high enough to submerge the locations of many of today's coastal cities. Understanding what caused seas to rise then could shed light on how to protect those cities today.

By examining fossil corals found on the Indian Ocean islands, University of Florida geochemist Andrea Dutton found evidence that global mean sea level during that period peaked at 20 to 30 feet above current levels. Dutton's team of international researchers concluded that rapid retreat of an unstable part of the Antarctic ice sheet was a major contributor to that sea-level rise."

New sulfate-breathing species discovered beneath ocean crust: Third of Earth's biomass in largely uncharted environment: "Two miles below the surface of the ocean, researchers have discovered new microbes that "breathe" sulfate. The microbes, which have yet to be classified and named, exist in massive undersea aquifers — networks of channels in porous rock beneath the ocean where water continually churns. About one-third of the Earth's biomass is thought to exist in this largely uncharted environment."

Chemical analysis of ancient rocks reveals earliest record yet of Earth's atmosphere: Isotopic memory of atmospheric persistence: "Chemical analysis of some of the world's oldest rocks has provided the earliest record yet of Earth's atmosphere. The results show that the air 4 billion years ago was very similar to that more than a billion years later, when the atmosphere — though it likely would have been lethal to oxygen-dependent humans — supported a thriving microbial biosphere that ultimately gave rise to the diversity of life on Earth today."

NASA Develops Volcano-Exploring Robots: "Volcanoes offer a number of roadblocks to exploration: Face-melting heat, daunting terrain and deep crevices. But scientists at NASA's Jet Propulsion Lab have designed two wall-climbing robots that can descend into fissures in volcanoes to better understand how they erupt.

Carolyn Parcheta, a NASA postdoctoral fellow, is working with JPL robotics researcher Aaron Parness to map a volcanic conduit system in Hawaii.

'We don't know exactly how volcanoes erupt,' Parcheta said in a statement. 'We have models but they are all very, very simplified. This project aims to help make those models more realistic.'"

Researchers find salmon semen can be used to extract rare earth elements from waste: "A team of researchers affiliated with several academic/research facilities in Japan has found that dried salmon semen can be used to extract rare earth elements (REEs) from liquid ore waste. In their paper published in the journal PLOS ONE, the team describes how they came up with the idea, the process they used, and the prospects of using their technique in commercial applications.

Currently, the process of retrieving REEs from ore waste involves the use of toxic and sometimes radioactive chemicals which often wind up in the environment causing problems. It is expensive too, because a special type of resin must be used. For that reason, scientists have been looking for other ways to get the job done. Back in 2010, another team of researchers discovered that phosphate on the surface of some types of bacteria attracted REEs allowing for collection of REEs—and it was ten times as efficient as current methods. The drawback, of course, was the difficulty in growing cultures for use on an industrial scale. In this new effort, the research team looked at dried salmon semen, known in Japan as milt, as a possible replacement.

Milt has phosphate in the sperm DNA, which the researchers reasoned, should attract REEs the same way that bacteria did in the early experiment. To find out, they poured the dry milt into a beaker that already contained a rare earth solution. Subsequent analysis revealed that the milt did indeed pull REEs from the solution, absorbing them. Putting the results in a centrifuge allowed the researchers to extract the REEs for repurposing. Notably, the process was able to extract the very expensive thulium and lutetium."

edited 17th Jan '15 12:12:07 AM by rmctagg09

Are earthquakes also earth burps?: "An 'excuse me' might be nice. Researchers have found that Earth belches a potent greenhouse gas known as tetrafluoromethane (CF 4) during earthquakes and other tectonic events. The emissions likely aren’t making a significant contribution to global warming, but the findings could change the way scientists model future climate scenarios. They also complicate the use of CF 4 as a way to measure how the continents and climate have changed over millennia."

Voyage from Earth's crust to its mantle and back again: "Uranium isotopes leave a distinct 'fingerprint' in the sources of volcanic rocks, making it possible to gauge their age and origin. Geologists have gained a new understanding of how Earth's crust is recycled back into its interior based on these uranium isotopes."

Geophysicists find the crusty culprits behind sudden tectonic plate movements: "New research may have solved one of the biggest mysteries in geology — namely, why do tectonic plates beneath the Earth's surface, which normally shift over the course of tens to hundreds of millions of years, sometimes move abruptly?"

WATCH: This is how the world’s only known natural nuclear reactor works: "Have you heard the one about how French scientists realised they were missing enough uranium-235 to make six atomic bombs, only to discover that it had been absent for 2 billion years? Hank Green's SciShow introduces us to the incredible Oklo natural nuclear reactor."

A 3-D view of the Greenland Ice Sheet opens window on ice history: "Scientists using ice-penetrating radar data collected by NASA's Operation IceBridge and earlier airborne campaigns have built the first comprehensive map of layers deep inside the Greenland Ice Sheet, opening a window on past climate conditions and the ice sheet's potentially perilous future.

This new map allows scientists to determine the age of large swaths of the second largest mass of ice on Earth, an area containing enough water to raise ocean levels by about 20 feet."

edited 24th Jan '15 12:51:32 AM by rmctagg09

The origin of life: Labyrinths as crucibles of life: "Water-filled micropores in hot rock may have acted as the nurseries in which life on Earth began. A team has now shown that temperature gradients in pore systems promote the cyclical replication and emergence of nucleic acids."

Missing link in metal physics explains Earth's magnetic field: "Earth's magnetic field shields the life on our planet's surface from cosmic rays. It is generated by turbulent motions of liquid iron in Earth's core. Iron is a metal, which means it can easily conduct a flow of electrons. New findings show that a missing piece of the traditional theory explaining why metals become less conductive when they are heated was needed to complete the puzzle of this field-generating process."