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Early Earth less hellish than previously thought

Early Earth less hellish than previously thought | Amazing Science | Scoop.it

Conditions on Earth for the first 500 million years after it formed may have been surprisingly similar to the present day, complete with oceans, continents and active crustal plates.


This alternate view of Earth’s first geologic eon, called the Hadean, has gained substantial new support from the first detailed comparison of zircon crystals that formed more than 4 billion years ago with those formed contemporaneously in Iceland, which has been proposed as a possible geological analog for early Earth.


The study was conducted by a team of geologists directed by Calvin Miller, the William R. Kenan Jr. Professor of Earth and Environmental Sciences at Vanderbilt University, and published online this weekend by the journal Earth and Planetary Science Letters in a paper titled, “Iceland is not a magmatic analog for the Hadean: Evidence from the zircon record.”


From the early 20th century up through the 1980’s, geologists generally agreed that conditions during the Hadean period were utterly hostile to life. Inability to find rock formations from the period led them to conclude that early Earth was hellishly hot, either entirely molten or subject to such intense asteroid bombardment that any rocks that formed were rapidly remelted. As a result, they pictured the surface of the Earth as covered by a giant “magma ocean.”


Two schools of thought have emerged: One argues that Hadean Earth was surprisingly similar to the present day. The other maintains that, although it was less hostile than formerly believed, early Earth was nonetheless a foreign-seeming and formidable place, similar to the hottest, most extreme, geologic environments of today. A popular analog is Iceland, where substantial amounts of crust are forming from basaltic magma that is much hotter than the magmas that built most of Earth’s current continental crust.


“We reasoned that the only concrete evidence for what the Hadean was like came from the only known survivors: zircon crystals – and yet no one had investigated Icelandic zircon to compare their telltale compositions to those that are more than 4 billion years old, or with zircon from other modern environments,” said Miller.

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Mystery solved: 'Sailing stones' of death valley seen in action for the first time

Mystery solved: 'Sailing stones' of death valley seen in action for the first time | Amazing Science | Scoop.it

Racetrack Playa is home to an enduring Death Valley mystery. Littered across the surface of this dry lake, also called a "playa," are hundreds of rocks – some weighing as much as 320 kilograms (700 pounds) – that seem to have been dragged across the ground, leaving synchronized trails that can stretch for hundreds of meters.

What powerful force could be moving them? Researchers have investigated this question since the 1940s, but no one has seen the process in action – until now. In a paper published in the journal PLOS ONE on Aug. 27, a team led by Scripps Institution of Oceanography, UC San Diego, paleobiologist Richard Norris reports on first-hand observations of the phenomenon.


Because the stones can sit for a decade or more without moving, the researchers did not originally expect to see motion in person. Instead, they decided to monitor the rocks remotely by installing a high-resolution weather station capable of measuring gusts to one-second intervals and fitting 15 rocks with custom-built, motion-activated GPS units. The National Park Service would not let them use native rocks, so they brought in similar rocks from an outside source.


The experiment was set up in winter 2011 with permission of the Park Service. Then – in what Ralph Lorenz of the Applied Physics Laboratory at the Johns Hopkins University, one of the paper's authors, suspected would be  "the most boring experiment ever" – they waited for something to happen.


But in December 2013, Norris and co-author and cousin Jim Norris arrived in Death Valley to discover that the playa was covered with a pond of water seven centimeters (three inches) deep. Shortly after, the rocks began moving.


"Science sometimes has an element of luck," Richard Norris said. "We expected to wait five or ten years without anything moving, but only two years into the project, we just happened to be there at the right time to see it happen in person."


Their observations show that moving the rocks requires a rare combination of events. First, the playa fills with water, which must be deep enough to form floating ice during cold winter nights but shallow enough to expose the rocks. As nighttime temperatures plummet, the pond freezes to form thin sheets of "windowpane" ice, which must be thin enough to move freely but thick enough to maintain strength. On sunny days, the ice begins to melt and break up into large floating panels, which light winds drive across the playa, pushing rocks in front of them and leaving trails in the soft mud below the surface.


"On Dec. 21, 2013, ice breakup happened just around noon, with popping and cracking sounds coming from all over the frozen pond surface," said Richard Norris. "I said to Jim, 'This is it!'"


The video in this article nicely explains how the non-aerodynamic rocks of Death Valley's Racetrack Playa move, leaving behind their trail in the hot desert.  Numerous attempts using GPS receivers and old-fashioned observations.  But observing ice in Death Valley is so rare that no one had ever seen it until now.  On very rare occasions, when it rains in the region, water will accumulate in the playa.  If the wind is powerful and consistent enough, the wind will push the panels of ice against these rocks and over time, the ice floes will push these rocks, leaving behind distinctive trails. This perfect combination of water, wind, ice and heat creates a remarkable signature on the landscape.

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Clam fossils offer 10,000 year history of El Nino Southern Oscillation

Clam fossils offer 10,000 year history of El Nino Southern Oscillation | Amazing Science | Scoop.it

A research team working in Peru, with members from France, Peru and the U.S. has found a way to track the El Niño Southern Oscillation (ENSO) going back as far as ten thousand years. In their paper published in the journal Science, the team reports that their study of clam fossils has revealed clear patterns of the ENSO and report that it has not been increasing in intensity over the course of the Holocene as some have suggested.

People have been living on the shores of the Pacific Ocean in Peru for a long time, and as they've done so, they've eaten clams, tossing the shells onto waste areas that grew to become huge mounds over thousands of years. In this new effort, the researchers dug down into several such mounds and extracted clam fossils they found, along with dirt and charcoal—remnants of ancient fires used to cook the clam meat. By taking measurements of oxygen isotopes in the clam shells, the researchers were able to calculate ocean surface temperatures at two to four week intervals throughout the lives of the individual clams, while radiocarbon dating of the dirt and charcoal revealed when the clams made their way into the mound. Examining multiple clams at different depths in the mounds allowed for creating a historical record of sea surface temperatures, and that allowed for charting the cycle of the ENSO going back ten thousand years.


The charts created by the research team suggest that the ENSO cycle does not have a predictable cycle and also that it has not been increasing in strength over the course of the Holocene as others have suggested. They did find some patterns, however. During a period approximately 4,000 to 5,000 years ago, for example, the ENSO was relatively weak, and during another period, from 6,700 to 7,500 years ago, ocean temperatures along the coast of Peru appeared to have been skewed by the location of warm water from an El Niño when trade winds push warm water into the Eastern Pacific.

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First pictures from inside the hole: 80-meter wide gaping hole appears in Siberia, no one knows how deep it goes and what caused it

First pictures from inside the hole: 80-meter wide gaping hole appears in Siberia, no one knows how deep it goes and what caused it | Amazing Science | Scoop.it

First pictures from inside the hole


Scientists have a good handle on the inner workings of the planet these days, but sometimes weird stuff happens that requires a little more investigation. Case in point, a giant hole 80 meters (262 feet) in diameter has appeared on the Siberian Yamal Peninsula. It certainly looks unusual, and scientists are still working to figure out what could cause this bizarre geological formation to appear.


A team of Russian scientists has been dispatched to analyze the crater, the depth of which is unknown at this time. Based on the images and video of the hole, geologists are positing a few hypotheses. Anna Kurchatova from Sub-Arctic Scientific Research Centre believes the crater was formed by water, salt, and natural gas mixing and causing an explosion. That’s a pretty satisfying explanation seeing as the hole totally looks like something exploded. The area was also a major gas field in the 1970s.


Dr. Chris Fogwill from the University of New South Wales in Australia has a different explanation. He posits that the mystery hole in Siberia is an especially striking example of a geological phenomenon called a pingo. A pingo is a large block of subterranean ice found in tundra environments that has grown into a small hill on the surface. If the ice hill thaws, the pingo can collapse, leaving only the crater where it used to be. Pingos are usually much smaller, but gas exploration and the geological changes that come with it could have contributed to this spectacular example.


Both of the potential explanations also figure in the increasing rate of global warming. Climate change has caused shifts in frozen permafrost that has been solid for millennia. Of course, there are still some who believe the Siberian hole to be a hoax.Teams are expected to arrive in the area within a day to report back, at which point we should know the truth — or at least have better pictures of a giant hole in the ground.


Via Joy Kinley
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Joy Kinley's curator insight, July 17, 2014 5:03 PM

The weird theories are out in force over this one.  What do you think caused this hole?

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Earth's magnetic field is weakening 10 times faster than originally predicted, swarm satellites show

Earth's magnetic field is weakening 10 times faster than originally predicted, swarm satellites show | Amazing Science | Scoop.it

Earth's magnetic field, which protects the planet from huge blasts of deadly solar radiation, has been weakening over the past six months, according to data collected by a European Space Agency (ESA) satellite array called Swarm.


The biggest weak spots in the magnetic field — which extends 370,000 miles (600,000 kilometers) above the planet's surface — have sprung up over the Western Hemisphere, while the field has strengthened over areas like the southern Indian Ocean, according to the magnetometers onboard the Swarm satellites — three separate satellites floating in tandem.


The scientists who conducted the study are still unsure why the magnetic field is weakening, but one likely reason is that Earth's magnetic poles are getting ready to flip, said Rune Floberghagen, the ESA's Swarm mission manager. In fact, the data suggest magnetic north is moving toward Siberia.


In fact over the past 20 million years, our planet has settled into a pattern of a pole reversal about every 200,000 to 300,000 years; as of 2012, however, it has been more than twice that long since the last reversal. These reversals aren't split-second flips, and instead occur over hundreds or thousands of years. During this lengthy stint, the magnetic poles start to wander away from the region around the spin poles (the axis around which our planet spins), and eventually end up switched around, according to Cornell University astronomers.

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Acid oceans threaten creatures that supply half the world's oxygen

Acid oceans threaten creatures that supply half the world's oxygen | Amazing Science | Scoop.it
Ocean acidification is turning phytoplankton toxic. Bad news for the many species - us, included - that rely on them as a principal source of food and oxygen.


What happens when phytoplankton, the (mostly) single-celled organisms that constitute the very foundation of the marine food web, turn toxic? Their toxins often concentrate in the shellfish and many other marine species (from zooplankton to baleen whales) that feed on phytoplankton. Recent trailblazing research by a team of scientists aboard the RV Melville shows that ocean acidification will dangerously alter these microscopic plants, which nourish a menagerie of sea creatures and produce up to 60 percent of the earth's oxygen.


The researchers worked in carbon saturated waters off the West Coast, a living laboratory to study the effects of chemical changes in the ocean brought on by increased atmospheric carbon dioxide. A team of scientists from NOAA's Fisheries Science Center and Pacific Marine Environmental Lab, along with teams from universities in Maine, Hawaii and Canada focused on the unique "upwelled" zones of California, Oregon and Washington. In these zones, strong winds encourage mixing, which pushes deep, centuries-old CO2 to the ocean surface. Their findings could reveal what oceans of the future will look like. The picture is not rosy.


Scientists already know that ocean acidification, the term used to describe seas soured by high concentrations of carbon, causes problems for organisms that make shells. “What we don't know is the exact effects ocean acidification will have on marine phytoplankton communities,” says Dr. Bill Cochlan, the biological oceanographer from San Francisco State University oceanographer who was the project’s lead investigator. “Our hypothesis is that ocean acidification will affect the quantity and quality of certain metabolities within the phytoplankton, specifically lipids and essential fatty acids.”

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M. Philip Oliver's curator insight, June 24, 2014 5:41 PM

Thanks Dr. Stefan

Scott Baker's curator insight, June 25, 2014 10:00 AM

will fertilization help?  http://nextbigfuture.com/2014/06/russ-george-blogged-about-fraser-river.html

Diane Johnson's curator insight, June 25, 2014 12:12 PM

Understanding systems and interdependence is just so critical!

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Massive body of water discovered towards Earth's core - 3 times bigger than all oceans combined

Massive body of water discovered towards Earth's core - 3 times bigger than all oceans combined | Amazing Science | Scoop.it

A huge expanse of water trapped in a layer of the Earth's mantle could help explain the origin of our oceans.


A reservoir of water three times the volume of all the oceans has been discovered deep beneath the Earth's surface. The water is hidden inside a blue rock called ringwoodite that lies 700 kilometres underground in the mantle, the layer of hot rock between Earth's surface and its core.


The huge size of the reservoir throws new light on the origin of Earth's water. Some geologists think water arrived in comets as they struck the planet, but the new discovery supports an alternative idea that the oceans gradually oozed out of the interior of the early Earth.

"It's good evidence the Earth's water came from within," says Steven Jacobsen of Northwestern University in Evanston, Illinois. The hidden water could also act as a buffer for the oceans on the surface, explaining why they have stayed the same size for millions of years.

Jacobsen's team used 2000 seismometers to study the seismic waves generated by more than 500 earthquakes. These waves move throughout Earth's interior, including the core, and can be detected at the surface. "They make the Earth ring like a bell for days afterwards," says Jacobsen.

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Tokelau: An Island 100% Powered By Solar Energy

Tokelau: An Island 100% Powered By Solar Energy | Amazing Science | Scoop.it

Tokelau (population: 1,500) is an island nation in the South Pacific, made up of three atolls whose highest point is only five meters above sea level. Even though the New Zealand protectorate’s contribution to climate change is miniscule, it faces grave threats to its very existence. In 2011, at the Durban Climate conference, Foua Toloa, the head of Tokelau, said the island would be using 100 percent renewable energy by 2012. By October of that year residents accomplished their goal, becoming the first country in the world to produce 100 percent of its electricity from the sun.


Prior to 2012, Tokelau’s residents relied on three diesel-driven power stations, burning 200 liters per day at a cost of nearly $800,000 per year. Tokelauans only had electricity 15 to 18 hours per day. They now have three solar photovoltaic systems, one on each atoll. The 4,032 solar panels (with a capacity of around one megawatt), 392 inverters, and 1,344 batteries provide 150 percent of their current electricity demand, allowing the Tokelauans to eventually expand their electricity use. In overcast weather, the generators run on local coconut oil, providing power while recharging the battery bank. The only fossil fuels used in Tokelau now are for the island nation’s three cars.

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Maria Isabel Ramos's curator insight, June 1, 2014 6:11 PM

Com o albedo de Castelo Branco podíamos estar como Tokelau.

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Filling a Seismic Gap: What Mexico has, and California is still lacking

Filling a Seismic Gap: What Mexico has, and California is still lacking | Amazing Science | Scoop.it

Mexico's government started to finance and build seismic alert systems shortly after the huge 8.1 quake, which devastated Mexico City in September 1985. Several years ago the various earthquake early warning initiatives in the country were integrated into Sasmex, which currently is able to detect and warn of earthquakes along the Pacific coast and in the central volcanic belt. Soon the alert system will be expanded into the states of Veracruz and Chiapas.


Mexico is not the only seismically active country in the world with such a warning system. Japan, Taiwan, Romania, Turkey and several other nations operate similar systems - but not the United States. Although the technology is available along the west coast (see blog on October 2, 2012) and a demonstration system is operating, a public alert system does not exist. California even has a law mandating Earthquake Early Warning, but this legislation has hardly any teeth, as it does not appropriate funds to build such a system. Mexico is clearly ahead of California when it comes to warning the populace of seismic shaking.

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Tour the Vegetation on Our Planet (provided by NASA/NOAA)

Although 75% of the planet is a relatively unchanging ocean of blue, the remaining 25% of Earth's surface is a dynamic green. Data from the NASA/NOAA Suomi NPP satellite is able to detect these subtle differences in greenness. The resources on this page highlight our ever-changing planet, using highly detailed vegetation index data from the satellite, developed by scientists at NOAA. The darkest green areas are the lushest in vegetation, while the pale colors are sparse in vegetation cover either due to snow, drought, rock, or urban areas. Satellite data from April 2012 to April 2013 was used to generate these animations and images.

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Volcanoes That Act as Air-Conditioning for a Warming World

Volcanoes That Act as Air-Conditioning for a Warming World | Amazing Science | Scoop.it

Many small eruptions over the past decade or so have helped restrain climate change.


On Valentine's Day, Indonesia's Mount Kelud blew its top and coated villages up to 500 kilometers away with ash. At the same time, the eruption injected a small but consequential amount of sulfur dioxide 28 kilometers up into the stratosphere. Tiny droplets of sulfuric acid then reflected away incoming sunlight, helping to cool the planet. Such “small” eruptions—along with others at places like Manam, Soufrière Hills, Jebel at Tair and Eyjafjallajökull, to name a few of the 17 between 2000 and 2012—have helped slow the pace of global warming, according to work published in Nature Geoscience.


“The uptick in early 21st-century volcanism clearly was a contributing factor to the hiatus,” says atmospheric scientist Benjamin Santer of Lawrence Livermore National Laboratory, lead author of the report. The volcanoes did not act alone. There was also an unusually quiescent sun, air pollution from China's coal-fired power plants and the mysterious workings of the ocean. Santer adds, “The net impact was to offset part of the human-caused greenhouse gas warming.”


In the meantime, global warming continues to gather strength, hidden behind volcanoes that may shutter their tops at any moment. Based on supersized eruptions such as Mount Pinatubo in the Philippines in 1991, reflective aerosols would then fall to Earth within a few years at most, leaving the planet exposed to the full heat-trapping effects of greenhouse gases from human activities.


If the volcanoes do not do their part, a last resort may be required—bring our own aerosols. Advocates of one form of geoengineering want to step in, injecting sulfate aerosols in the stratosphere to augment or replace eruptions. Such deliberate tinkering with planetary-scale systems has been proposed as a fallback plan if climate change were to turn catastrophic, though at the cost of the stratospheric layer that helps to shield life from ultraviolet light. Sulfuric acid high in the sky has the unfortunate side effect of eliminating ozone. But given the inertia in reducing greenhouse gas pollution, the debate around geoengineering will undoubtedly linger longer than the aftermath of these small volcanic eruptions.

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Today’s Antarctic region once as hot as California or Florida

Today’s Antarctic region once as hot as California or Florida | Amazing Science | Scoop.it

Parts of ancient Antarctica were as warm as today’s California coast, and polar regions of the southern Pacific Ocean registered 21st-century Florida heat, according to scientists using a new way to measure past temperatures.


The findings, published the week of April 21, 2014 in the Proceedings of the National Academy of Sciences, underscore the potential for increased warmth at Earth’s poles and the associated risk of melting polar ice and rising sea levels, the researchers said.


Led by scientists at Yale, the study focused on Antarctica during the Eocene epoch, 40-50 million years ago, a period with high concentrations of atmospheric CO2 and consequently a greenhouse climate. Today, Antarctica is year-round one of the coldest places on Earth, and the continent’s interior is the coldest place, with annual average land temperatures far below zero degrees Fahrenheit.


But it wasn’t always that way, and the new measurements can help improve climate models used for predicting future climate, according to co-author Hagit Affek of Yale, associate professor of geology & geophysics.


“Quantifying past temperatures helps us understand the sensitivity of the climate system to greenhouse gases, and especially the amplification of global warming in polar regions,” Affek said.

The paper’s lead author, Peter M.J. Douglas, performed the research as a graduate student in Affek’s Yale laboratory. He is now a postdoctoral scholar at the California Institute of Technology. The research team included paleontologists, geochemists, and a climate physicist.


By measuring concentrations of rare isotopes in ancient fossil shells, the scientists found that temperatures in parts of Antarctica reached as high as 17 degrees Celsius (63F) during the Eocene, with an average of 14 degrees Celsius (57F)  — similar to the average annual temperature off the coast of California today.

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Deanmignanelli's curator insight, July 15, 2014 10:34 PM

due to the current extreme climate changes the polar ice caps are melting due to carbon gases and this melting of the caps is causing major rising in the sea levels which is causeing disaster around the world due to water comming up past the sea barriers

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There is an Ocean Full of Water Deep Inside the Earth

There is an Ocean Full of Water Deep Inside the Earth | Amazing Science | Scoop.it

In what sounds like a chapter from Journey to the Center of the Earth, the chemical makeup of a tiny, extremely rare gemstone has made researchers think there's a massive water reservoir hundreds of miles under the earth.


The gemstone in question is called ringwoodite, which is created when olivine, a material that is extremely common in the mantle, is highly pressurized; when it’s exposed to less pressurized environments, it reverts into olivine. It has previously been seen in meteorites and created in a laboratory, but until now it had never been found in a sample of the earth’s mantle.


Diamond expert Graham Pearson of the University of Alberta came across a seemingly worthless, three-millimeter piece of brown diamond that had been found in Mato Grosso, Brazil, while he was researching another type of mineral. Within that diamond, he and his team found ringwoodite—and they found that roughly 1.5 percent of the ringwoodite’s weight was made up of trapped water. The findings are published in Nature.


That water had to get in there somehow, and using analyses of its depth and its water makeup, Pearson suggests that there's water deep under the earth's surface—a lot of it.


The finding “confirms predictions from high-pressure laboratory experiments that a water reservoir comparable in size to all the oceans combined is hidden deep in Earth’s mantle,” according to an analysis of Pearson’s findings by Hans Keppler of the University of Bayreuth in Germany. 


The earth’s crust, including the deepest parts of the oceans, reach depths of roughly 100 kilometers. From there, the upper mantle takes up about another 300 kilometers. Between there and the lower mantle is where this piece of ringwoodite was originally from—an area between 410 and 660 kilometers beneath the earth’s surface known as the “transition zone.” 


Scientists have long been divided about what, exactly, is in the transition zone. We’ve known that much of the upper mantle is made up of olivine, and as Keppler said, scientists have long thought that Earth contained reservoirs of water deep beneath the crust. But they weren’t sure whether the water existed as low as the transition zone—the area between the upper and lower mantles. While some say that much of the oceans’ water may have originated there, others have said it is likely completely dry.


Pearson’s finding changes that. In the paper, he says that there are two possible explanations for water within the ringwoodite. “In one, water within the ringwoodite reflects inheritance from a hydrous, diamond-forming fluid, from which the inclusion grew as a syngenetic phase. In this model, the hydrous fluid must originate locally, from the transition zone, because there is no evidence that the lower mantle contains a significant amount of water,” he wrote. Essentially, the extreme pressure and chemical makeup at those depths spontaneously creates water. 


“Alternatively, the ringwoodite is ‘protogenetic,’ that is, it was present before encapsulation by the diamond and its water content reflects that of the ambient transition zone," Pearson wrote. In that model, the water and the ringwoodite are already there, and the ringwoodite absorbs some of the water. Either way you slice it, there is a lot of water in the transition zone: “Both models implicate a transition zone that is at least locally water-rich,” he wrote.


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Future of Oceanography: Crowdsourcing the Collection of Oceanographic Data

Future of Oceanography: Crowdsourcing the Collection of Oceanographic Data | Amazing Science | Scoop.it

We live on a vast, underexplored planet that is largely ocean. Despite modern technology, Global Positioning System (GPS) navigation, and advanced engineering of ocean vessels, the ocean is unforgiving, especially in rough weather. Coastal ocean navigation, with risks of running aground and inconsistent weather and sea patterns, can also be challenging and hazardous. In 2012, more than 100 international incidents of ships sinking, foundering, grounding, or being lost at sea were reported (http://en.wikipedia.org/wiki/List_of_shipwrecks_in_2012). Even a modern jetliner can disappear in the ocean with little or no trace[1], and the current costs and uncertainty associated with search and rescue make the prospects of finding an object in the middle of the ocean daunting [2].


Notwithstanding satellite constellations, autonomous vehicles, and more than 300 research vessels worldwide (www.wikipedia.org/wiki/List_of_research_vessels_by_country), we lack fundamental data relating to our oceans. These missing data hamper our ability to make basic predictions about ocean weather, narrow the trajectories of floating objects, or estimate the impact of ocean acidification and other physical, biological, and chemical characteristics of the world's oceans. To cope with this problem, scientists make probabilistic inferences by synthesizing models with incomplete data. Probabilistic modeling works well for certain questions of interest to the scientific community, but it is difficult to extract unambiguous policy recommendations from this approach. The models can answer important questions about trends and tendencies among large numbers of events but often cannot offer much insight into specific events. For example, probabilistic models can tell us with some precision the extent to which storm activity will be intensified by global climate change but cannot yet attribute the severity of a particular storm to climate change. Probabilistic modeling can provide important insights into the global traffic patterns of floating debris but is not of much help to search-and-rescue personnel struggling to learn the likely trajectory of a particular piece of debris left by a wreck.


Oceanographic data are incomplete because it is financially and logistically impractical to sample everywhere. Scientists typically sample over time, floating with the currents and observing their temporal evolution (the Langrangian approach), or they sample across space to cover a gradient of conditions—such as temperature or nutrients (the Eulerian approach). These observational paradigms have various strengths and weaknesses, but their fundamental weakness is cost. A modern ocean research vessel typically costs more than US$30,000 per day to operate—excluding the full cost of scientists, engineers, and the cost of the research itself. Even an aggressive expansion of oceanographic research budgets would not do much to improve the precision of our probabilistic models, let alone to quickly and more accurately locate missing objects in the huge, moving, three-dimensional seascape. Emerging autonomous technologies such as underwater gliders and in situ biological samplers (e.g., environmental sample processors) help fill gaps but are cost prohibitive to scale up. Similarly, drifters (e.g., the highly successful Argo floats program) have proven very useful for better defining currents, but unless retrieved after their operational lifetime, they become floating trash, adding to a growing problem.


Long-term sampling efforts such as the continuous plankton recorder in the North Sea and North Atlantic [3] provide valuable data on decadal trends and leveraged English Channel ferries to accomplish much of the sampling. Modernizing and expanding this approach is a goal of citizen science initiatives.

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Lorraine Chaffer's curator insight, September 12, 2014 10:38 PM

Option topic: Marine environmental change and management

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Widespread methane leakage from ocean floor off the US coast

Widespread methane leakage from ocean floor off the US coast | Amazing Science | Scoop.it

Researchers say they have found more than 500 bubbling methane vents on the seafloor off the US east coast. The unexpected discovery indicates there are large volumes of the gas contained in a type of sludgy ice called methane hydrate. There are concerns that these new seeps could be making a hitherto unnoticed contribution to global warming.

The scientists say there could be about 30,000 of these hidden methane vents worldwide.


Previous surveys along the Atlantic seaboard have shown only three seep areas beyond the edge of the US continental shelf. The findings came as a bit of a surprise.  "It is the first time we have seen this level of seepage outside the Arctic that is not associated with features like oil or gas reservoirs or active tectonic margins," said Prof Adam Skarke from Mississippi State University, who led the study.


The scientists have observed streams of bubbles but they have not yet sampled the gas within them. However, they believe there is an abundance of circumstantial evidence pointing to methane.


Most of the seeping vents were located around 500m down, which is just the right temperature and pressure to create a sludgy confection of ice and gas called methane hydrate, or clathrate.


The scientists say that the warming of ocean temperatures might be causing these hydrates to send bubbles of gas drifting through the water column. 


Prof. Skarke and his colleagues estimate that worldwide, there may be around 30,000 of the type of seeps they have discovered.

They acknowledge that this is a rough calculation but they believe that it could be significant.


While the vents may not be posing an immediate global warming threat, the sheer number means that our calculations on the potential sources of greenhouse gases may need revising. The scientists also found abundant life around many of these seeps, but not perhaps as we know it.


The creatures they describe are termed chemosynthetic, meaning they derive energy from chemical reactions and not from the Sun as do photosynthetic organisms.

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Mysterious Siberian crater attributed to methane released from thawing permafrost

Mysterious Siberian crater attributed to methane released from thawing permafrost | Amazing Science | Scoop.it

A mystery crater spotted in the frozen Yamal peninsula in Siberia earlier this month was probably caused by methane released as permafrost thawed, researchers in Russia say.


Air near the bottom of the crater contained unusually high concentrations of methane — up to 9.6% — in tests conducted at the site on 16 July, says Andrei Plekhanov, an archaeologist at the Scientific Centre of Arctic Studies in Salekhard, Russia. Plekhanov, who led an expedition to the crater, says that air normally contains just 0.000179% methane.


Since the hole was spotted in mid-July by a helicopter pilot, conjecture has abounded about how the 30-metre-wide crater was formed — a gas or missile explosion, a meteorite impact and alien involvement have all been suggested.


But Plekhanov and his team believe that it is linked to the abnormally hot Yamal summers of 2012 and 2013, which were warmer than usual by an average of about 5°C. As temperatures rose, the researchers suggest, permafrost thawed and collapsed, releasing methane that had been trapped in the icy ground.

Other researchers argue that long-term global warming might be to blame — and that a slow and steady thaw in the region could have been enough to free a burst of methane and create such a big crater. Over the past 20 years, permafrost at a depth of 20 metres has warmed by about 2°C, driven by rising air temperatures1, notes Hans-Wolfgang Hubberten, a geochemist at the Alfred Wegener Institute in Potsdam, Germany.
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Japan earthquake has raised pressure below Mount Fuji, says new study

Japan earthquake has raised pressure below Mount Fuji, says new study | Amazing Science | Scoop.it

Mount Fuji, or Fujisan as it is known in Japanese, is the highest point on the archipelago (rising to 3,776 metres) and the national emblem, immortalised in countless etchings. In June last year Unesco added it to the World Heritage list as a "sacred place and source of artistic inspiration". But it is still an active volcano, standing at the junction between the Pacific, Eurasian and Philippine tectonic plates. Though it has rarely stirred in recorded history, it is still potentially explosive.


The Tohoku – or Great East Japan – earthquake on 11 March 2011 triggered a devastating tsunami, which in turn caused the Fukushima Daiichi nuclear disaster. According to a Franco-Japanese study published by Science (PDF), the magnitude-9 tremor also increased the pressure on Mount Fuji. "Our work does not say that the volcano will start erupting, but it does show that it's in a critical state," says Florent Brenguier, a researcher at the Institute of Earth Sciences (IST) in Grenoble, France, and lead author of the publication, to which the Institute of Global Physics (IPG) in Paris also contributed.


Adopting a novel approach, the scientists carried out a sort of giant echo-scan of the bowels of the Earth, based on the huge mass of data recorded after the mega-quake by Japan's Hi-net system, the densest network in the world, with 800 seismic sensors. They focused on signals commonly known as seismic noise, the result of constant interaction between ocean swell and "solid" earth. In the past such data has generally been dismissed as background interference.


By recording fluctuations in this barely perceptible subterranean noise they were able to map geological disturbances in the bedrock of Japan caused by the seismic waves following the violent quake in March 2011. "Seismic waves travel a very long way, going round the world several times," Brenguier explains. "Their movement makes the Earth's crust vibrate, and rather like a shock wave this produces breaks or cracks in the rock."

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How wet is Earth's soil? NASA's Aquarius Returns Global Maps of Soil Moisture

How wet is Earth's soil? NASA's Aquarius Returns Global Maps of Soil Moisture | Amazing Science | Scoop.it

Soil moisture, the water contained within soil particles, is an important player in Earth's water cycle. It is essential for plant life and influences weather and climate. Satellite readings of soil moisture will help scientists better understand the climate system and have potential for a wide range of applications, from advancing climate models, weather forecasts, drought monitoring and flood prediction to informing water management decisions and aiding in predictions of agricultural productivity.


Launched June 10, 2011, aboard the Argentinian spacecraft Aquarius/Satélite de Aplicaciones Científicas (SAC)-D, Aquarius was built to study the salt content of ocean surface waters. The new soil wetness measurements were not in the mission's primary science objectives, but a NASA-funded team led by U.S. Department of Agriculture (USDA) researchers has developed a method to retrieve soil moisture data from the instrument's microwave radiometer.


The Aquarius measurements are considerably coarser in spatial resolution than the measurements from the upcoming NASASoil Moisture Active Passive (SMAP) mission, which was specifically designed to provide the highest quality soil moisture measurements available, including a spatial resolution 10 times that offered by Aquarius.


Soils naturally radiate microwaves and the Aquarius sensor can detect the microwave signal from the top 2 inches (5 centimeters) of the land, a signal that subtly varies with changes in the wetness of the soil. Aquarius takes eight days to complete each worldwide survey of soil moisture, although with gaps in mountainous or vegetated terrain where the microwave signal becomes difficult to interpret.

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Is There A Remnant Ancient Earth Lodged Deep Inside Earth's Mantle?

Is There A Remnant Ancient Earth Lodged Deep Inside Earth's Mantle? | Amazing Science | Scoop.it

A team of scientists from Harvard University believe that have found evidence that an ancient Earth exists inside the Earth.


The team believes that a previously unexplained isotopic ratio from deep within the Earth might be a signal from material from before the Earth collided with another planet-sized body, which led to the creation of the Moon. This might be an echo of an ancient Earth that existed 4.5 billion years ago, prior to the proposed collision.


The current favored theory says that the Moon was formed 4.5 billion years ago when the Earth collided with a mass the size of Mars, dubbed “Theia.” This theory states that the heat generated by the collision would have melted the whole planet before some of the debris spun off to create the Moon.


But now, the team at Harvard, led by Associate Professor Sujoy Mukhopadhyay, believe that they’ve found evidence to support that only part of the Earth melted, and that an ancient part still exists within the Earth’s mantle.


According to Professor Mukhopadhyay: “The energy released by the impact between the Earth and Theia would have been huge, certainly enough to melt the whole planet. But we believe that the impact energy was not evenly distributed throughout the ancient Earth. This means that a major part of the impacted hemisphere would probably have been completely vaporized, but the opposite hemisphere would have been partly shielded, and would not have undergone complete melting.”

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Rising global temperatures could increase the amount of carbon dioxide naturally released by the world's oceans

Rising global temperatures could increase the amount of carbon dioxide naturally released by the world's oceans | Amazing Science | Scoop.it

Fresh insight into how the oceans can affect CO2 levels in the atmosphere shows that rising temperatures can indirectly increase the amount of the greenhouse gas emitted by the oceans.


Scientists studied a 26,000-year-old sediment core taken from the Gulf of California to find out how the ocean's ability to take up atmospheric CO2 has changed over time.


They tracked the abundance of the key elements silicon and iron in the fossils of tiny marine organisms, known as plankton, in the sediment core. Plankton absorb CO2 from the atmosphere at the ocean surface, and can lock away vast quantities of carbon.

Researchers found that those periods when silicon was least abundant in ocean waters corresponded with relatively warm climates, low levels of atmospheric iron, and reduced CO2 uptake by the oceans' plankton. Scientists had suspected that iron might have a role in enabling plankton to absorb CO2. However, this latest study shows that a lack of iron at the ocean surface can limit the effect of other key elements in helping plankton take up carbon.


This effect is magnified in the southern ocean and equatorial Pacific and coastal areas, which are known to play a crucial role in influencing levels of CO2 in the global atmosphere.


Researchers from the University of Edinburgh say their findings are the first to pinpoint the complex link between iron and other key marine elements involved in regulating atmospheric CO2 by the oceans. Their findings were verified with a global calculation for all oceans. The study, published in Nature Geoscience, was supported by Scottish Alliance for Geoscience Environment Society and the Natural Environment Research Council.

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Extreme summer: MIT study finds that springtime ozone levels are good predictors of summertime temperatures

Extreme summer: MIT study finds that springtime ozone levels are good predictors of summertime temperatures | Amazing Science | Scoop.it

MIT study finds that springtime ozone levels are good predictors of summertime temperatures. The link between springtime ozone and summertime temperatures is particularly strong for the present period, while ozone is still in a recovery phase. When the researchers examined this link from a period before the ozone hole had begun to form, they observed a much weaker correlation.


The implication, Bandoro says, is that as ozone levels likely rise in the coming decades, these parts of the Southern Hemisphere will probably experience systematically hotter summers. 


“We can expect that these types of summers are going to be more frequent as the ozone hole recovers in coming decades,” Bandoro says. “When the ozone hole is deep, it essentially holds back climate change from showing its face, and Australia is just starting to feel this effect in the summertime in years with shallower ozone holes.”


David Karoly, a professor of earth sciences at the University of Melbourne, says the MIT group has shown, for the first time, a strong relationship between the severity of summer temperatures in Australia and the strength of the ozone hole the previous spring. The results, he says, point to a long-term warming trend in the Southern Hemisphere.


“As the ozone hole recovers this century, the masking effects of ozone depletion causing reduced summer warming over the Southern Hemisphere will disappear,” says Karoly, who did not participate in the study. “Then there will be an acceleration of the summer warming trends over Australia and South Africa, as the ozone hole recovers and the masking influence disappears.”

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The World's Oldest Underground Fire Has Been Burning For 6,000 Years

The World's Oldest Underground Fire Has Been Burning For 6,000 Years | Amazing Science | Scoop.it

If you've heard of underground coal fires, then you've probably heard of the one raging under the abandoned town of Centralia, Pennsylvania, since 1962. Fifty-two years is a long time—and a lot of coal—but that's barely a blink compared to Burning Mountain in Australia, which has been ablaze for 6,000 years.


Coal seam fires are incredibly common, as it happens, and thousands of them are now burning underground across the world. A coal seam some 700 miles south of Australia's Burning Mountain caught fire a month ago, spewing poisonous gases and prompting intense firefighting efforts. Once an subterranean coal seam fire gets out of hand—as in Centralia, as in Burning Mountain—it's nearly impossible to put out.


At Burning Mountain, also known as Mount Wingen, sulfur-tinged smoke is the only hint of a massive coal seam burning 70 feet under the ground. Heat and toxic gases from the fire have left it rocky and jagged in parts, and the land has caved in.


How the mountain was first set ablaze is a mystery. It could have been a lightning strike, forest fire, spontaneous combustion, or even aboriginal burning practices could even have been the initial spark.


It's with human intervention that coal seam fires have really caught on, so to speak, in the past century. Mining exposes coal to oxygen, and coal, as we know, burns very, very easily. With plenty of fuel and oxygen, a small spark can ignite a blaze that grows to cover miles and miles.


China, with its thousands of small-scale mines, and India, with its crumbling old and large mines, have the most serious underground fire problems. The burning coal releases potentially toxic elements like arsenic, fluorine, and selenium into the air.

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Tree rings reveal nightmare droughts in the West

Tree rings reveal nightmare droughts in the West | Amazing Science | Scoop.it
If you think the 1930s drought that caused The Dust Bowl was rough, new research looking at tree rings in the Rocky Mountains has news for you: Things can get much worse in the West.


In fact the worst drought of this century barely makes the top 10 of a study that extended Utah’s climate record back to the year 1429. With sandpaper and microscopes, Brigham Young University professor Matthew Bekker analyzed rings from drought-sensitive tree species. He found several types of scenarios that could make life uncomfortable in what is now the nation’s third-fastest-growing state: 


Long droughts: The year 1703 kicked off 16 years in a row with below average stream flow.


Intense droughts: The Weber River flowed at just 13 percent of normal in 1580 and dropped below 20 percent in three other periods.


Consecutive worst-case scenarios: The most severe drought in the record began in 1492, and four of the five worst droughts all happened during Christopher Columbus’ lifetime. 


“We’re conservatively estimating the severity of these droughts that hit before the modern record, and we still see some that are kind of scary if they were to happen again,” said Bekker, a geography professor at BYU. “We would really have to change the way we do things here.” 


Modern climate and stream flow records only go back about 100 years in this part of the country, so scientists like Bekker turn to Mother Nature’s own record-keeping to see the bigger picture. For this study, the BYU geographer took sample cores from Douglas fir and pinyon pine trees. The thickness of annual growth rings for these species is especially sensitive to water supply. 


Using samples from both living and dead trees in the Weber River basin, the researchers built a tree-ring chronology that extends back 585 years into Utah’s natural history. Modern stream flow measurements helped them calibrate the correlation between ring thickness and drought severity.


As Bekker and his co-authors report in the Journal of the American Water Resources Association, the west’s climate usually fluctuates far more than it did in the 1900s. The five previous centuries each saw more years of extremely dry and extremely wet climate conditions. 

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Asteroid and Meteorite Impacts Can Preserve Biodata for Millions of Years

Asteroid and Meteorite Impacts Can Preserve Biodata for Millions of Years | Amazing Science | Scoop.it

In two separate studies, geologists led by Dr. Haley Sapers from the University of Western Ontario and Dr. Pete Schultz of Brown University have found floral, microbial and organic matter in glass created by ancient asteroid, comet and meteorite impacts. Such glass samples could provide a snapshot of environmental conditions at the time of those impacts and could be a good place to look for signs of ancient life on Mars.


In the first study, published in the journal Geology, Dr Schultz with colleagues found fragments of leaves and preserved organic compounds lodged inside glass created by a several ancient impacts in Argentina. “The soil of eastern Argentina, south of Buenos Aires, is rife with impact glass created by at least seven different impacts that occurred between 6,000 and 9 million years ago,” Dr Schultz explained. “One of those impacts, dated to around 3 million years ago, coincides with the disappearance of 35 animal genera.”

“We know these were major impacts because of how far the glass is distributed and how big the chunks are. These glasses are present in different layers of sediment throughout an area about the size of Texas,” he said.


Within glass associated with two of those impacts – one from 3 million years ago and one from 9 million years ago – the team found exquisitely preserved plant matter.


In the second study, published also in the journal Geology, Dr Sapers and her colleagues discovered microbes preserved in impact glass. They analyzed tubular features in hydrothermally altered impact glass from the Ries Impact Structure, Germany, that are remarkably similar to the bioalteration textures observed in volcanic glasses.


Mineral-forming processes cannot easily explain the distribution and shapes of the Ries tubular features; therefore, they suggest the tubules formed by microbes etching their way through the impact glass as they excreted organic acids.


A meteorite impact into a water-rich target such as Earth or Mars has the potential to generate a post-impact hydrothermal system.

Impact structures, especially post-impact hydrothermal systems, represent an understudied habitat with potential relevance to early life and the evolution of early life on Earth.


Understanding the biological significance of impact products such as impact glass on Earth will better inform the search for evidence of life and past life on other terrestrial planets such as Mars.

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MIT: U.N. Warns Crops Are at Greater Risk than Thought from Climate Change

MIT: U.N. Warns Crops Are at Greater Risk than Thought from Climate Change | Amazing Science | Scoop.it

A few years ago scientists thought climate change wouldn’t cause much harm to overall food production until temperatures in a region rose by three to four degrees Celsius compared to current levels. But in the latest United Nations report on climate change, released today, scientists have revised those estimates, pointing to significant losses with a temperature rise of just two degrees Celsius.


The report is part of the Fifth Assessment Report from the Intergovernmental Panel on Climate Change, a group of 837 researchers from around the world who assess and summarize the scientific literature on climate change. The fourth assessment report came out in 2007, and since then scientists have accumulated far more data, revised their computer models, and done more to study how factors such as changes in precipitation and extreme weather interact.


Changes in crop yield—the amount of produced per hectare—are only one part of the current report, which has over 30 chapters. But the changes in scientists’ estimates of how climate change will affect agriculture are some of the most remarkable in the report. The report, looking at the major food crops of corn, wheat, and rice, says that yields are likely to start decreasing by 2030 and decline up to 2 percent a decade (climate change seems to be affecting crops already, but so far this has been offset by improvements in crop yield). Such a reduction in yield is particularly worrying because demand for food is expected to increase in coming years, at a rate of about 2 percent a year.


Assessing how climate change will affect crops is tricky. Increased concentrations of carbon dioxide, changes in temperature and precipitation, the increased frequency of extremely hot days, and changing patterns of crop disease all play a role. In some areas, climate change could help improve production—growing seasons may improve in cold areas, for example. But scientists are finding that even with current levels of warming, the negative impacts of climate change are more common. And as the climate continues to change, the negative impacts are expected to get worse.

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