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Parched West is using up underground water

U.S. Bureau of Reclamation Surface-water depletion in the Colorado River Basin has left this “bathtub ring” of mineral deposits on Lake Mead, but groundwater loss is invisible. Credit: U.S. Bureau of Reclamation

A new study by University of California, Irvine and NASA scientists finds more than 75 percent of the water loss in the drought-stricken Colorado River Basin since late 2004 came from underground resources. The extent of groundwater loss may pose a greater threat to the water supply of the western United States than previously thought.
This study is the first to quantify the amount that groundwater contributes to the water needs of western states. According to the U.S. Bureau of Reclamation, the federal water management agency, the basin has been suffering from prolonged, severe drought since 2000 and has experienced the driest 14-year period in the last hundred years.

The research team used data from NASA’s Gravity Recovery and Climate Experiment (GRACE) satellite mission to track changes in the mass of the Colorado River Basin, which are related to changes in water amount on and below the surface. Monthly measurements in the change in water mass from December 2004 to November 2013 revealed the basin lost nearly 53 million acre feet (65 cubic kilometers) of freshwater, almost double the volume of the nation’s largest reservoir, Nevada’s Lake Mead. More than three-quarters of the total — about 41 million acre feet (50 cubic kilometers) — was from groundwater.

“We don’t know exactly how much groundwater we have left, so we don’t know when we’re going to run out,” said Stephanie Castle, a water resources specialist at UC Irvine and the study’s lead author. “This is a lot of water to lose. We thought that the picture could be pretty bad, but this was shocking.”

Water above ground in the basin’s rivers and lakes is managed by the U.S. Bureau of Reclamation, and its losses are documented. Pumping from underground aquifers is regulated by individual states and is often not well documented.

“There’s only one way to put together a very large-area study like this, and that is with satellites,” said senior author Jay Famiglietti, senior water cycle scientist at JPL on leave from UC Irvine, where he is an Earth system science professor. “There’s just not enough information available from well data to put together a consistent, basin-wide picture.”

Famiglietti said GRACE is like having a giant scale in the sky. Within a given region, the change in mass due to rising or falling water reserves influences the strength of the local gravitational attraction. By periodically measuring gravity regionally, GRACE reveals how much a region’s water storage changes over time.

The Colorado River is the only major river in the southwest part of the United States. Its basin supplies water to about 40 million people in seven states, as well as irrigating roughly four million acres of farmland.

“The Colorado River Basin is the water lifeline of the western United States,” said Famiglietti. “With Lake Mead at its lowest level ever, we wanted to explore whether the basin, like most other regions around the world, was relying on groundwater to make up for the limited surface-water supply. We found a surprisingly high and long-term reliance on groundwater to bridge the gap between supply and demand.”

Famiglietti noted that the rapid depletion rate will compound the problem of short supply by leading to further declines in streamflow in the Colorado River.

“Combined with declining snowpack and population growth, this will likely threaten the long-term ability of the basin to meet its water allocation commitments to the seven basin states and to Mexico,” Famiglietti said.

The study has been accepted for publication in the journal Geophysical Research Letters, which posted the manuscript online July 24. Coauthors included other scientists from NASA’s Goddard Space Flight Center, Greenbelt, Md.; and the National Center for Atmospheric Research, Boulder, Colo. The research was funded by NASA and the University of California.

Note : The above story is based on materials provided by University of California – Irvine.

Synchronization of North Atlantic, North Pacific preceded abrupt warming, end of ice age

This image depicts the Hubbard Glacier ice front, with floating ice ‘growlers’ in August 2004. Credit: Photo courtesy of Oregon State University

Scientists have long been concerned that global warming may push Earth’s climate system across a “tipping point,” where rapid melting of ice and further warming may become irreversible — a hotly debated scenario with an unclear picture of what this point of no return may look like.
A newly published study by researchers at Oregon State University probed the geologic past to understand mechanisms of abrupt climate change. The study pinpoints the emergence of synchronized climate variability in the North Pacific Ocean and the North Atlantic Ocean a few hundred years before the rapid warming that took place at the end of the last ice age about 15,000 years ago.

The study suggests that the combined warming of the two oceans may have provided the tipping point for abrupt warming and rapid melting of the northern ice sheets.

Results of the study, which was funded by the National Science Foundation, appear this week in Science.

This new discovery by OSU researchers resulted from an exhaustive 10-year examination of marine sediment cores recovered off southeast Alaska where geologic records of climate change provide an unusually detailed history of changing temperatures on a scale of decades to centuries over many thousands of years.

“Synchronization of two major ocean systems can amplify the transport of heat toward the polar regions and cause larger fluctuations in northern hemisphere climate,” said Summer Praetorius, a doctoral student in marine geology at Oregon State and lead author on the Science paper. “This is consistent with theoretical predictions of what happens when Earth’s climate reaches a tipping point.”

“That doesn’t necessarily mean that the same thing will happen in the future,” she pointed out, “but we cannot rule out that possibility.”

The study found that synchronization of the two regional systems began as climate was gradually warming. After synchronization, the researchers detected wild variability that amplified the changes and accelerated into an abrupt warming event of several degrees within a few decades.

“As the systems become synchronized, they organized and reinforced each other, eventually running away like screeching feedback from a microphone,” said Alan Mix, a professor in OSU’s College of Earth, Ocean, and Atmospheric Sciences and co-author on the paper. “Suddenly you had the combined effects of two major oceans forcing the climate instead of one at a time.”

“The example that we uncovered is a cause for concern because many people assume that climate change will be gradual and predictable,” Mix added. “But the study shows that there can be vast climate swings over a period of decades to centuries. If such a thing happened in the future, it could challenges society’s ability to cope.”

What made this study unusual is that the researchers had such a detailed look at the geologic record. While modern climate observations can be made every day, the length of instrumental records is relatively short — typically less than a century. In contrast, paleoclimatic records extend far into the past and give good context for modern changes, the researchers say. However, the resolution of most paleo records is low, limited to looking at changes that occur over thousands of years.

In this study, the researchers examined sediment cores taken from the Gulf of Alaska in 2004 during an expedition led by Mix. The mountains in the region are eroding so fast that sedimentation rates are “phenomenal,” he said. “Essentially, this rapid sedimentation provides a ‘climate tape recorder’ at extremely high fidelity.”

Praetorius then led an effort to look at past temperatures by slicing the sediment into decade-long chunks spanning more than 8,000 years — a laborious process that took years to complete. She measured ratios of oxygen isotopes trapped in fossil shells of marine plankton called foraminifera. The isotopes record the temperature and salinity of the water where the plankton lived.

When the foraminifera died, their shells sank to the sea floor and were preserved in the sediments that eventually were recovered by Mix’s coring team.

The researchers then compared their findings with data from the North Greenland Ice Core Project to see if the two distinct high-latitude climate systems were in any way related.

Most of the time, the two regions vary independently, but about 15,500 years ago, temperature changes started to line up and then both regions warmed abruptly by about five degrees (C) within just a few decades. Praetorius noted that much warmer ocean waters likely would have a profound effect on northern-hemisphere climates by melting sea ice, warming the atmosphere and destabilizing ice sheets over Canada and Europe.

A tipping point for climate change “may be crossed in an instant,” Mix noted, “but the actual response of the Earth’s system may play out over centuries or even thousands of years during a period of dynamic adjustment.”

“Understanding those dynamics requires that we look at examples from the past,” Mix said. “If we really do cross such a boundary in the future, we should probably take a long-term perspective and realize that change will become the new normal. It may be a wild ride.”

Added Praetorius: “Our study does suggest that the synchronization of the two major ocean systems is a potential early warning system to begin looking for the tipping point.”

Note : The above story is based on materials provided by Oregon State University.

How much magma is hiding beneath our feet? Mysteries of Earth’s crust pierced

How much magma is hiding beneath our feet? Credit: © naypong / Fotolia

Molten rock (or magma) has a strong influence on our planet and its inhabitants, causing destructive volcanic eruptions and generating some of the giant mineral deposits. Our understanding of these phenomena is, however, limited by the fact that most magma cools and solidifies several kilometres beneath our feet, only to be exposed at the surface, millions of years later, by erosion. Scientists have never been able to track the movements of magma at such great depths… that is, until a team from the University of Geneva (UNIGE) discovered an innovative technique, details of which will be published in the next issue of the journal Nature.

It is a story of three scientists: a modelling specialist, an expert in a tiny mineral known as “zircon,” and a volcanologist. Following a casual conversation, the researchers stumbled upon an idea, and eventually a new method to estimate the volume and flow of magma required for the construction of magma chambers was shaped. The technique they developed makes it possible to refine predictions of future volcanic eruptions as well as identifying areas of the planet that are rich in magma-related natural resources.

Zircon: a valuable mineral for scientists

Professor Urs Schaltegger has been studying zircon for more than ten years in his laboratory at UNIGE, one of the world’s few labs in this field. “The zircon crystals that are found in solidified magma hold key information about the injection of molten rock into a magma chamber before it freezes underground,” explains the professor. Zircon contains radioactive elements that enable researchers to determine its age. As part of the study, the team from the Section of Earth and Environmental Sciences of UNIGE paired data collected using natural samples and numerical simulation. As Guy Simpson, a researcher at UNIGE further explains: “Modelling meant that we could establish how the age of crystallised zircon in a cooled magma reservoir depends on the flow rate of injected magma and the size of the reservoir.”

Applications for society and industry

In the Nature article, the researchers propose a model that is capable of determining with unprecedented accuracy the age, volume and injection rate of magma that has accumulated at inaccessible depths. As a result, they have established that the formation of Earth’s crust, volcanic super eruptions and mineral deposits occur under very specific yet different conditions. Professor Luca Caricchi adds: “When we determine the age of a family of zircons from a small sample of solidified magmatic rock, using results from the mathematical model we have developed, we can tell what the size of the entire magma chamber was, as well as how fast the magma reservoir grew.” The professor continues: “This information means that we can determine the probability of an explosive volcanic eruption of a certain size to occur. In addition, the model will be of interest to industry because we will be able to identify new areas of our planet that are home to large amounts of natural resources such as copper and gold.”

Journal Reference:

Luca Caricchi, Guy Simpson, Urs Schaltegger. Zircons reveal magma fluxes in the Earth’s crust. Nature, 2014; 511 (7510): 457 DOI: 10.1038/nature13532

Note : The above story is based on materials provided by Université de Genève.

3-D image of Paleolithic child’s skull reveals trauma, brain damage

This is a 3-D reconstruction of skull compound fracture and endocranial surface changes. Credit: Coqueugniot H, Dutour O, Arensburg B, Duday H, Vandermeersch B, et al. (2014) Earliest Cranio-Encephalic Trauma from the Levantine Middle Palaeolithic: 3D Reappraisal of the Qafzeh 11 Skull, Consequences of Pediatric Brain Damage on Individual Life Condition and Social Care. PLoS ONE 9(7): e102822. doi:10.1371/journal.pone.0102822

Three-dimensional imaging of a Paleolithic child’s skull reveals potentially violent head trauma that likely lead to brain damage, according to a study published July 23, 2014 in the open-access journal PLOS ONE by Hélène Coqueugniot and colleagues from CNRS — Université de Bordeaux and EPHE.
A Paleolithic child that lived ~100 thousand years ago found at Qafzeh in lower Galilee, was originally thought to have a skull lesion that resulted from a trauma that healed. The child died at about 12-13 years old, but the circumstances surround the child’s death remain mysterious. To better understand the injury, the authors of this study aimed to re-appraise the child’s impact wound using 3D imaging, which allows scientists to better to explore inner bone lesions, to evaluate their impact on soft tissues, and to estimate brain size to reconstruct the events surrounding the skull trauma.

3D reconstruction reveals that the child’s skull fracture appears to be compound, with a broken piece depressed in the skull, surrounded by linear fractures. The authors suggest that this fracture type generally results from a blunt force trauma, often a result of interpersonal violence, but can also occur accidentally. The depressed fracture was likely caused a moderate traumatic brain injury, possibly resulting in personality changes, trouble controlling movements, and difficulty in social communication. The authors conclude that, the child represents the oldest documented human case of severe skull trauma available from south-western Asia. Furthermore, the child appears to have received special social attention after death, as the body positioning seems intentional with two deer antlers lying on the upper part of the adolescent’s chest, likely suggesting a deliberate ceremonial burial.

Hélène Coqueugniot added, “Digital imaging and 3D reconstruction evidenced the oldest traumatic brain injury in a Paleolithic child. Post-traumatic neuropsychological disorders could have impaired social life of this individual who was buried, when teenager, with a special ritual raising the question of compassion in Prehistory.”

Journal Reference:

Coqueugniot H, Dutour O, Arensburg B, Duday H, Vandermeersch B, et al. Earliest Cranio-Encephalic Trauma from the Levantine Middle Palaeolithic: 3D Reappraisal of the Qafzeh 11 Skull, Consequences of Pediatric Brain Damage on Individual Life Condition and Social Care. PLoS ONE, 2014 DOI: 10.1371/journal.pone.0102822

Note : The above story is based on materials provided by PLOS.

Oso disaster had its roots in earlier landslides

An aerial view of the slide site at Oso, Washington, from March 31, 2014. Credit: Gordon Farquharson / UW

The disastrous March 22 landslide that killed 43 people in the rural Washington state community of Oso involved the “remobilization” of a 2006 landslide on the same hillside, a new federally sponsored geological study concludes.
The research indicates the landslide, the deadliest in U.S. history, happened in two major stages. The first stage remobilized the 2006 slide, including part of an adjacent forested slope from an ancient slide, and was made up largely or entirely of deposits from previous landslides. The first stage ultimately moved more than six-tenths of a mile across the north fork of the Stillaguamish River and caused nearly all the destruction in the Steelhead Haven neighborhood.

The second stage started several minutes later and consisted of ancient landslide and glacial deposits. That material moved into the space vacated by the first stage and moved rapidly until it reached the trailing edge of the first stage, the study found.

The report, released Tuesday on the four-month anniversary of the slide, details an investigation by a team from the Geotechnical Extreme Events Reconnaissance Association, or GEER. The scientists and engineers determined that intense rainfall in the three weeks before the slide likely was a major issue, but factors such as altered groundwater migration, weakened soil consistency because of previous landslides and changes in hillside stresses played key roles.

The extreme events group is funded by the National Science Foundation, and its goal is to collect perishable data immediately in the wake of extreme events such as earthquakes, hurricanes, tsunamis, landslides or floods. Recent events for which reports have been filed include earthquakes in New Zealand and Haiti, the 2011 earthquake and tsunami in Japan, and Hurricane Sandy on the U.S. Eastern Seaboard in 2012.

“Perhaps the most striking finding is that, while the Oso landslide was a rare geologic occurrence, it was not extraordinary,” said Joseph Wartman, a University of Washington associate professor of civil and environmental engineering and a team leader for the study.

“We observed several other older but very similar long-runout landslides in the surrounding Stillaguamish River Valley. This tells us these may be prevalent in this setting over long time frames. Even the apparent trigger of the event — several weeks of intense rainfall — was not truly exceptional for the region,” Wartman said.

Team co-leader Jeffrey Keaton, a principal engineering geologist with AMEC Americas, an engineering consultant and project management company, said another important finding is that spring of 2014 was not a big time for landslides in Northwest Washington.

“The Oso landslide was the only major one that occurred in Snohomish County or the Seattle area this spring,” Keaton said.

Other team members are Scott Anderson of the Federal Highway Administration, Jean Benoit of the University of New Hampshire, John deLaChapelle of Golder Associates Inc., Robert Gilbert of the University of Texas and David Montgomery of the University of Washington.

The team was formed and approved within days of the landslide, but it began work at the site about eight weeks later, after search and recovery activities were largely completed. The researchers documented conditions and collected data that could be lost over time. Their report is based largely on data collected during a four-day study of the entire landslide area in late May. It focuses on data and observations directly from the site, but also considers information such as local geologic and climate conditions and eyewitness accounts.

The researchers reviewed evidence for a number of large landslides in the Stillaguamish Valley around Oso during the previous 6,000 years, many of them strongly resembling the site of the 2014 slide. There is solid evidence, for example, of a slide just west of this year’s slide that also ran out across the valley. In addition, they reviewed published maps showing the entire valley bottom in the Oso area is made up of old landslide deposits or areas where such deposits have been reworked by the river and left on the flood plain.

The team estimated that large landslides such as the March event have happened in the same area as often as every 400 years (based on 15 mapped large landslides) to every 1,500 years (based on carbon dating of what appears to be the oldest of four generations of large slides) during the last six millennia.

The researchers found that the size of the landslide area grew slowly starting in the 1930s until 2006, when it increased dramatically. That was followed by this year’s catastrophically larger slide.

Studies in previous decades indicated a high landslide risk for the Oso area, the researchers found, but they noted that it does not appear there was any publicly communicated understanding that debris from a landslide could run as far across the valley as it did in March. In addition to the fatalities, that event seriously injured at least 10 people and caused damage estimated at more than $50 million.

“For me, the most important finding is that we must think about landslides in the context of ‘risk’ rather than ‘hazard,'” Wartman said. “While these terms are often used interchangeably, there is a subtle but important difference. Landslide hazard, which was well known in the region, tells us the likelihood that a landslide will occur, whereas landslide risk tells us something far more important — the likelihood that human losses will occur as a result of a landslide.

“From a policy perspective, I think it is very important that we begin to assess and clearly communicate the risks from landslides,” he said.

Other study conclusions include:

• That past landslides and associated debris deposited by water should be carefully investigated when mapping areas for zoning purposes.

• That the influence of precipitation on destabilizing a slope should consider both cumulative amounts and short-duration intensities in assessing the likelihood of initial or renewed slope movement.

• That methods to identify and delineate potential landslide runout zones need to be revisited and re-evaluated.

The report is available at http://www.geerassociation.org/GEER_Post%20EQ%20Reports/Oso_WA_2014/index.html

Note : The above story is based on materials provided by University of Washington. The original article was written by Vince Stricherz.

Researchers figure out how oddly shaped sandstone landform structures come about

Delicate Arch, Arches National Park, Utah, USA. Credit: Jaroslav Soukup

A team of researchers with members from facilities in the Czech Republic and one from the U.S. has discovered the mechanism by which unique sandstone landforms take shape. In their paper published in Nature Geoscience, the team describes how their studies of sandstone in their lab led to insights about how both gravity and erosion contribute to the creation of such unique structures as Delicate Arch at Arches National Park in Utah. Chris Paola of the University of Minnesota offers a News & Views piece on the research done by the team in the same journal issue.
For many years, scientists have assumed it was wind and rain along with freezing and thawing that accounted for uniquely shaped sandstone landforms—they occur in many places and generally cause those who see them to take a second—or third look. Many believed they came about because some of the rock was just naturally harder than other parts. The results were sometimes awe inspiring structures that at times appeared to defy gravity. But now, new research suggests that it’s actually gravity that allows the structures to form in the first place.

Curious as to the real mechanism by which sandstone landforms take shape, the researchers took several samples into their lab and subjected them to intense scrutiny—after cutting the samples into cubes, they used pressure plates to simulate the loads of real structures while also subjecting them to simulated wind and rain. As the cubes were deformed, close inspection revealed that in the parts of the sandstone subjected to direct pressure (simulated gravity) individual grains tended to lock together creating sections of stone that were more resilient to wind and rain. That led to the creation of pillars within the sandstone that stood strong as the grains around them were swept away. As more free grains were swept away, more pressure was exerted on the column causing the grains in them to lock even tighter.

The team found that when pressure was applied from above to different parts of a cube, and artificial cracks and other perturbations were also introduced to the sandstone, it led to the development of interesting and unique shapes when subjected to simulated erosion. The researchers believe this same action applies to sandstone in its natural state, and accounts for the remarkable shapes that have left those beholding them wondering how they could have formed and then withstood the ravages of wind and rain—it’s because their columns have been made strong enough to withstand further weathering.

More information: 
Sandstone landforms shaped by negative feedback between stress and erosion, Nature Geoscience (2014) DOI: 10.1038/ngeo2209

Abstract

Weathering and erosion of sandstone produces unique landforms1, 2 such as arches, alcoves, pedestal rocks and pillars. Gravity-induced stresses have been assumed to not play a role in landform preservation3 and to instead increase weathering rates4, 5. Here we show that increased stress within a landform as a result of vertical loading reduces weathering and erosion rates, using laboratory experiments and numerical modelling. We find that when a cube of locked sand exposed to weathering and erosion processes is experimentally subjected to a sufficiently low vertical stress, the vertical sides of the cube progressively disintegrate into individual grains. As the cross-sectional area under the loading decreases, the vertical stress increases until a critical value is reached. At this threshold, fabric interlocking of sand grains causes the granular sediment to behave like a strong, rock-like material, and the remaining load-bearing pillar or pedestal landform is resistant to further erosion. Our experiments are able to reproduce other natural shapes including arches, alcoves and multiple pillars when planar discontinuities, such as bedding planes or fractures, are present. Numerical modelling demonstrates that the stress field is modified by discontinuities to make a variety of shapes stable under fabric interlocking, owing to the negative feedback between stress and erosion. We conclude that the stress field is the primary control of the shape evolution of sandstone landforms.

Note : The above story is based on materials provided by © 2014 Phys org

Jeju Island, Korea is a live volcano

Pictures of the sedimentary layer containing charcoal found on a stony mountain developing site in Sangchang-ri, and the carbonized wood (charcoal) sample used for the radiocarbon dating. Thick lava covers the upper gravel layer. Credit: Image courtesy of Korea Institute of Geoscience and Mineral Resources (KIGAM)

In Jeju, Korea, a place emerging as a world-famous vacation spot with natural tourism resources, a recent study revealed a volcanic eruption occurred on the island. The Korea Institute of Geoscience and Mineral Resources (KIGAM) indicated that there are the traces that indicated that a recent volcanic eruption was evident 5,000 years ago. This is the first time the date of the explosion has been made clear in the region.
The research team led by Dr. Jin-Young Lee confirmed in results from radiocarbon dating for carbonized wood (charcoal) found below the basaltic layer located in Sangchang-ri, Seogwipo-si, Jeju-do it dated back to 5,000 years ago; which means the time when the basalt on the upper layer was formed took place relatively recently, i.e. 5,000 years ago, and which demonstrates that the island has experienced a volcanic eruption fairly recently.

The latest volcanic eruption occurring on Jeju Island was volcanic activity known to have spewed around 7,000 years ago at Mt. Songak. The basaltic layer in Sangchang-ri is known to be formed due to the eruption in the vicinity of Byeongak Oreum 35,000 years ago; though, this study revealed that the layer is a product of the most recent volcanic activity among those known ever. Volcanic activity at Mt. Songak was limited hydro volcanic activity out of which a great deal of volcanic ash was released while it is evident that Sangchang-ri was a dynamic active volcano out of which lava was spewed and then flowed down in all directions along the inland slope.

It is also remarkable that the research team enhanced the accuracy of the findings in the radiocarbon dating technique using carbonized wood, consequently raising the reliability of the findings. Until now, previous research used the dating method for rocks covering the upper sedimentary layer, in which such dating method with the relatively longer half-life period shows limitations in determining the time the basalt was formed about 10,000 years ago.

In order to overcome the limitations of the dating method for the rocks covering the upper sedimentary layer, the research team led by Dr. Jin-Young Lee concurrently used radiocarbon dating and optically stimulated luminescence dating (OSL), using such cross-validation of which raised the accuracy of tracing the past volcanic activities.

Judging from the findings, Jeju Island is not an extinct volcano, but seems to rather be a potentially live volcano because a volcano that has erupted within 10,000 years is defined to be a live volcano on a geological basis.

Not remaining complacent for the findings, the research team plans to continuously conduct the studies on the time the volcanic rocks were formed in several regions on the island in order to identify the latest volcanic activity.

Note : The above story is based on materials provided by Korea Institute of Geoscience and Mineral Resources (KIGAM).

New water balance calculation for Dead Sea

Sinkholes and surface springs in Samar (Western Dead Sea), the Jordan flank of the Dead Sea is visible in the background. Credit: Dr. Christian Siebert/UFZ

The drinking water resources on the eastern, Jordanian side of the Dead Sea could decline severe as a result of climate change than those on the western, Israeli and Palestinian side. This is the conclusion reached by an international team of researchers that calculated the water flows around the Dead Sea. The natural replenishment rate of groundwater will reduce dramatically in the future if precipitation lowers as predicted, say the scientists, writing in the journal Science of the Total Environment. Even now, the available groundwater resources in the region are not sufficient to meet the growing water requirements of the population and agriculture. If the situation worsens, it could therefore have serious social, economic and ecological consequences for the region.

Important data for water providers

A reliable inventory of existing water resources around the Dead Sea, on the border between Israel, Palestine and Jordan, forms the basis for sustainable water management. The lowest lake on earth is not only one of the biggest tourist attractions in the Middle East; more than four million people rely on the groundwater resources in its catchment basin. For a long time, the complex hydrology of this region presented major unknown factors in the local water balance equation. To some extent it still does. Thanks to improved computer simulations, the researchers were able to work out — on an international scale for the first time — how much water actually infiltrates from rainfall and replenishes the groundwater reservoir: around 281 million cubic metres per year. This means that we now also know what the maximum withdrawal limit should be if this resource is to be managed sustainably.

A complicated puzzle with many pieces

Since the 1960s, the majority of the Dead Sea’s tributaries have been dammed to capture the precious water before it disappears into the salt lake. However, this apparent salvaging of water is causing the water level of the Dead Sea to fall by around a metre per year and, with it, the surrounding groundwater levels. Fresh water springs thousands of years old are ebbing away. This much was already known. What was not clear was exactly what impact the retreating water levels have on the quantities of usable groundwater. Over the past five years, the team of researchers from Germany, Israel, Jordan and Palestine working on the SUMAR research project therefore used a combination of comprehensive on-site measurements, remote sensing and computer modelling systems to be able to provide a fairly complete answer to this question.

Tracing the course of the water

The springs in and around the Dead Sea were identified using infra-red sensors on aircraft and satellites, as well as chemical and isotopic methods. “By analysing rare earth elements in particular we were able to trace the origin of the water and the routes it takes underground,” reports Dr Christian Siebert of the Centre for Environmental Research (UFZ). “Not only were we able to locate 37 areas where groundwater flows into the Dead Sea, we now also know the history of each source. This was important for finding out how much fresh water flows into the Dead Sea underground and is therefore no longer available to use as drinking water. The last passage in particular, before the water from the mountains reaches the lake, took us a long time,” says the hydrogeologist. “Here, salt water rising from below mixes with the fresh water, and salt minerals are dissolved in it. But, together with colleagues from the Max Planck Institute in Bremen, we also managed to identify the biogeochemical processes that make permanent changes to the groundwater.”

Computer models calculate the total water balance

In the end, all the available data were fed into computer models that revealed, more accurately than ever before, the situation in the drainage basin in the immediate vicinity of the Dead Sea — an area measuring roughly 7000 square kilometres. The biggest challenges were the heterogeneous distribution of urban areas and the associated gaps in the data. Whereas the number of measuring stations in and around built-up areas like Jerusalem and Amman is very high, there are broad stretches of land that are very sparsely populated and therefore have only few wells and almost no geological or meteorological data. Yet rain is particularly important in this context. The region is characterised by short, heavy downpours that often fall over a very small area. For this reason, the project team set up its own measurement stations so as to be able to measure the flash floods that result from these downpours. A comprehensive flow-measuring station was also set up on the River Jordan near one of the baptismal sites that attract thousands of Christian pilgrims every year.

Bleak forecasts

Using the models, the scientists were able, for the first time, to make predictions about possible future changes in the groundwater resources that are so vital for this region: the western (Israeli-Palestinian) side of the lake receives almost twice as much rainfall as the eastern (Jordanian) side. As a result, groundwater replenishment rates are currently around 50 per cent higher on the western side. Climate scenarios predict a decrease in annual rainfall of around 20 per cent. However, the water that currently ends up underground and replenishes these important groundwater resources would be halved. The decrease on the western Israeli-Palestinian side is expected to be around 45 per cent, whereas the water available for the Jordanian (eastern) side would fall by nearly 55 per cent. The social and economic situation could therefore worsen, in Jordan in particular.

Recycling as a way out of the water crisis

Saving and reusing water could therefore be a solution, and the UFZ researchers are developing this concept further with colleagues from Israel, Palestine and Jordan. For instance, the SMART project researched ways of stabilising water supply in the Middle East. The UFZ developed new concepts for decentralised wastewater treatment and made a significant contribution to the water master plan of Jordan, one of the world’s most arid countries. Great importance was attached to adapting the wastewater treatment concept to local conditions, and to collaborating with local scientists and authorities. A special implementation office was set up in Jordan’s Ministry of Water in Amman.

Ongoing research

Since completion of the SUMAR project, the research has been continued by the Helmholtz centres KIT (Karlsruhe), GFZ (Potsdam), UFZ (Halle) and local partners within the DESERVE (DEad SEa Research VEnue) project. The aim of the meteorologists, hydrogeologists, geologists and geophysicists involved in the project is to look at environmental risks, water availability and climate change as a whole, so as to develop solutions for this unique region, not only so that people will be able to continue to visit the biblical sites, but also so that the people of this region can continue to live there. A stable water supply will therefore play an important role in bringing peace to the Middle East. Whether the region will ever build the canal intended to carry water from the Red Sea to the Dead Sea remains to be seen. Scientists like Christian Siebert are critical of the possible consequences of importing water in this way: “For instance, it is unclear whether the much lighter ocean water will mix with the Dead Sea water, which is ten times more saline, and we cannot be sure what biological and chemical processes will take place.” The impacts on the surrounding groundwater are also disputed. Tilo Arnhold

Note : The above story is based on materials provided by Helmholtz Centre for Environmental Research – UFZ.

Mammoth and mastodon behavior was less roam, more stay at home

Research led by UC’s Brooke Crowley, posing with this mammoth mandible, has uncovered some interesting ideas about mammoth and mastodon behavior. Credit: Dottie Stover, UC Creative Services

Their scruffy beards weren’t ironic, but there are reasons mammoths and mastodons could have been the hipsters of the Ice Age.
According to research from the University of Cincinnati, the famously fuzzy relatives of elephants liked living in Greater Cincinnati long before it was trendy — at the end of the last ice age. A study led by Brooke Crowley, an assistant professor of geology and anthropology, shows the ancient proboscideans enjoyed the area so much they likely were year-round residents and not nomadic migrants as previously thought.

They even had their own preferred hangouts. Crowley’s findings indicate each species kept to separate areas based on availability of favored foods here at the southern edge of the Last Glacial Maximum’s major ice sheet.

“I suspect that this was a pretty nice place to live, relatively speaking,” Crowley says. “Our data suggest that animals probably had what they needed to survive here year-round.”

Could the past save the future?

Crowley’s research with co-author and recent UC graduate Eric Baumann, “Stable Isotopes Reveal Ecological Differences Among Now-Extinct Proboscideans from the Cincinnati Region, USA,” was recently published in Boreas, an international academic research journal.

Learning more about the different behaviors of these prehistoric creatures could benefit their modern-day cousins, African and Asian elephants. Both types are on the World Wildlife Fund’s endangered species list. Studying how variable different types of elephants might have been in the past, Crowley says, might help ongoing efforts to protect these largest of land mammals from continued threats such as poaching and habitat destruction.

“There are regionally different stories going on,” Crowley says. “There’s not one overarching theme that we can say about a mammoth or a mastodon. And that’s becoming more obvious in studies people are doing in different places. A mammoth in Florida did not behave the same as one in New York, Wyoming, California, Mexico or Ohio.”

The wisdom in teeth

For their research, Crowley and Baumann looked to the wisdom in teeth — specifically museum specimens of molars from four mastodons and eight mammoths from Southwestern Ohio and Northwestern Kentucky. Much can be revealed by carefully drilling a tooth’s surface and analyzing the stable carbon, oxygen and strontium isotopic signatures in the powdered enamel.

Each element tells a different story. Carbon provides insight into an animal’s diet, oxygen relates to overall climatic conditions of an animal’s environment and strontium indicates how much an animal may have traveled at the time its tooth was forming.

“Strontium reflects the bedrock geology of a location,” Crowley says. “So if a local animal grows its tooth and mineralizes it locally and dies locally, the strontium isotope ratio in its tooth will reflect the place where it lived and died. If an animal grows its tooth in one place and then moves elsewhere, the strontium in its tooth is going to reflect where it came from, not where it died.”

Their analysis allowed them to determine several things:

  • Mammoths ate more grasses and sedges than mastodons, which favored leaves from trees or shrubs.
  • Strontium from all of the animals (except one mastodon) matched local water samples, meaning they likely were less mobile and migratory than previously thought.
  • Differences in strontium and carbon between mammoths and mastodons suggest they didn’t inhabit the same localities.
  • Mammoths preferred to be closer to the retreating ice sheet where grasses were more abundant, whereas mastodons fed farther from the ice sheet in more forested habitat.

“As a geologist, questioning the past is one of the most interesting and exciting things to do,” says Baumann, an environmental geologist with a contractor for the U.S. Environmental Protection Agency. “Based on our data, mammoths and mastodons seemed to have different diets and lived in different areas during their lives. This is important because it allows us to understand how species in the past lived and interacted. And the past is the key to the present.”

Note : The above story is based on materials provided by University of Cincinnati. The original article was written by Tom Robinette

Science and art bring back to life 300-million-year-old specimens of a primitive reptile-like vertebrate

Cranial reconstruction of Gephyrostegus bohemicus. Credit: Image courtesy of University of Lincoln

Paleontologists from the Natural History Museum and academics from Lincoln, Cambridge and Solvakia have recreated the cranial structure of a 308-million-year-old lizard-like vertebrate that could be the earliest example of a reptile and explain the origin of all vertebrates that belong to reptiles, birds and mammals.
Dr Marcello Ruta, from the School of Life Sciences, University of Lincoln, UK, was one of the authors of the paper which is published in the Journal of Vertebrate Paleontology and produced a series of intricate hand-drawn recreations of the cranial structure of Gephyrostegus.

Paleontologists have provided a new cranial reconstruction of a long-extinct limbed vertebrate (tetrapod) from previously unrecognised specimens found in coal deposits from the Czech Republic.

The team of academics reviewed the cranial structural features of the Late Carboniferous Gephyrostegus bohemicus — a small animal of generally lizard-like build that lived 308 million years ago.

This early tetrapod could be the earliest example of a reptile and explain the origin of amniotes, all vertebrates that belong to reptiles, birds and mammals.

Experts from, Comenius University in Bratislava (Slovakia), University Museum of Zoology in Cambridge, The Natural History Museum in London, and the University of Lincoln, UK, have been able to study additional specimens unavailable in previous works.

Their aim was to provide an analysis of early tetrapod relationships incorporating their new observations of Gephyrostegus. Their analysis used skeletal traits across a sample of early tetrapod groups to identify the likely affinities of Gephyrostegus.

Their results are detailed in the Journal of Vertebrate Paleontology.

Dr Marcello Ruta, from the School of Life Sciences, University of Lincoln, UK, was one of the authors and produced a series of intricate hand-drawn recreations of the cranial structure of Gephyrostegus.

He explained: “Gephyrostegus has always been an elusive beast. Several researchers have long considered the possibility that the superficially reptile-like features of this animal might tell us something about amniote ancestry. But Gephyrostegus also shows some much generalised skeletal features that make the issue of its origin even more problematic. We conducted a new study that brings together data from a large number of early tetrapods. The study shows that Gephyrostegus is closely related to another group of Eurasiatic and North American tetrapods called seymouriamorphs, also involved in debates about amniote ancestry. We found some interesting new cranial features in Gephyrostegus that helped us establish this link.

“Staring at specimens for a long time down a microscope and trying to make sense of their anatomy may be frustrating and tiring at times, but always immensely rewarding.”

Note : The above story is based on materials provided by University of Lincoln.

Oceans vital for possibility for alien life

Planet Earth. New research shows the vital role of oceans in moderating climate on Earth-like planets. The presence of oceans is vital for optimal climate stability and habitability, according to a new article. Credit: NASA/ GSFC/ NOAA/ USGS

Researchers at the University of East Anglia have made an important step in the race to discover whether other planets could develop and sustain life.
New research published today in the journal Astrobiology shows the vital role of oceans in moderating climate on Earth-like planets.

Until now, computer simulations of habitable climates on Earth-like planets have focused on their atmospheres. But the presence of oceans is vital for optimal climate stability and habitability.

The research team from UEA’s schools of Mathematics and Environmental Sciences created a computer simulated pattern of ocean circulation on a hypothetical ocean-covered Earth-like planet. They looked at how different planetary rotation rates would impact heat transport with the presence of oceans taken into account.

Prof David Stevens from UEA’s school of Maths said: “The number of planets being discovered outside our solar system is rapidly increasing. This research will help answer whether or not these planets could sustain alien life.

“We know that many planets are completely uninhabitable because they are either too close or too far from their sun. A planet’s habitable zone is based on its distance from the sun and temperatures at which it is possible for the planet to have liquid water.

“But until now, most habitability models have neglected the impact of oceans on climate.

“Oceans have an immense capacity to control climate. They are beneficial because they cause the surface temperature to respond very slowly to seasonal changes in solar heating. And they help ensure that temperature swings across a planet are kept to tolerable levels.

“We found that heat transported by oceans would have a major impact on the temperature distribution across a planet, and would potentially allow a greater area of a planet to be habitable.

“Mars for example is in the sun’s habitable zone, but it has no oceans — causing air temperatures to swing over a range of 100OC. Oceans help to make a planet’s climate more stable so factoring them into climate models is vital for knowing whether the planet could develop and sustain life.

“This new model will help us to understand what the climates of other planets might be like with more accurate detail than ever before.”

‘The Importance of Planetary Rotation Period for Ocean Heat Transport’ is published in the journal Astrobiology on Monday, July 21, 2014. The research was funded by the Engineering and Physical Sciences Research Council (EPSRC).

Note : The above story is based on materials provided by University of East Anglia.

Experts map deep magma reservoir below Washington’s Mt. Rainier

Hawaii Volcanoes National Park National Park Service

(Reuters) – Experts have mapped a huge magma reservoir below Mount Rainier in Washington state that begins melting deep in the Earth’s mantle before pushing upwards to where it will eventually be tapped for eruption.
Researchers from the United States and Norway used seismic imaging and the measurement of variations in electrical and magnetic fields to create a detailed road map of the pathway molten rock takes to the surface.

Their findings, published this week in the journal Nature, are aimed at helping experts understand the volcano’s inner workings, and eventually determine when it might again erupt.

A state landmark, Mount Rainier last erupted in the 19th century. It is widely expected to erupt again, according to the U.S. National Park Service.

The tallest volcano and fifth-highest peak in the contiguous United States, it towers some 14,410-feet (4,392 meters) about 58 miles (93 km) southeast of Seattle, from most of which it is visible.

Phil Wannamaker, a geophysicist at the University of Utah, said the new images were most detailed to date, but that they did not provide any information on the timing of future eruptions by Mount Rainier or other Cascade Range volcanoes.

The volcano’s magma forms deep in the Earth’s mantle, the layer between the planet’s crust and its core. The magma, which is fluid molten rock, then flows upwards to a pool about five miles (8 km) below the peak, the study found.

The pool appears to be about 5 to 10 miles (8 km to 16 km) thick and the same width, the researchers said.

Note : The above story (Reporting by Victoria Cavaliere; Editing by Daniel Wallis and Eric Walsh)

Estimating earthquake frequency and patterns in the Puget Lowland

Credit: Nelson et al.

The hazard posed by large earthquakes is difficult to estimate because they often occur hundreds to thousands of years apart. Because written records for the Puget Lowland of northwestern Washington cover less than 170 years, the size and frequency of the largest and oldest earthquakes on the Seattle and Tacoma faults are unknown. Past earthquakes can only be estimated through geologic studies of sediments and landforms that are created when faults break the ground surface.

Along the Cascadia margin, the cities of Seattle and Tacoma occupy the Puget Lowland, a structurally complex, seismically active forearc trough between the Coast Range and the Cascade volcanic arc. Deformation of the lowland is caused by the clockwise motion of western Oregon, pushing northward and compressing western Washington against slower moving Canada. Much of the north- to northeast-directed strain in the southern Puget Lowland is accommodated by deformation in the Seattle fault zone, the Tacoma fault zone, the Saddle Mountain deformation zone, and along the Olympia fault.

In their paper for GEOSPHERE, published online 25 June 2014, Alan R. Nelson and colleagues write that although in 1992 a very large earthquake on the Seattle fault was dated to a thousand years ago, the size and frequency of earlier earthquakes on active faults of the southern Puget Lowland remains uncertain. Through a synthesis of earlier geologic data with new field evidence of earthquake faulting at nine sites on the Seattle and Tacoma faults, Nelson and colleagues show that four or five earthquakes large enough to break the ground surface occurred on the Seattle fault or related faults during the past 3,500 years.

More information:
“Diverse rupture modes for surface-deforming upper plate earthquakes in the southern Puget Lowland of Washington State.” Alan R. Nelson et al., Geologic Hazards Science Center, U.S. Geological Survey, MS 966, PO Box 25046, Denver, Colorado 80225, USA. Published online 25 June 2014; dx.doi.org/10.1130/GES00967.1

Note : The above story is based on materials provided by Geological Society of America

Japan earthquake has raised pressure below Mount Fuji, says new study

Proximity of Mount Fuji to the epicentre of the March 2011 earthquake. Christine Oliver/Guardian Source: Le Monde

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.”

One might well imagine that such disturbance is greatest close to the epicentre of a quake, but this is not the case. The Franco-Japanese study shows that the area where the Earth’s crust suffered the greatest damage was not around Tohoku, in the north-east of Honshu island, but in the volcanic regions, in particular under Mount Fuji, some 400km away. “The volcanic regions are the ones where the fluids trapped in the rock – boiling water, gas, liquid magma, which cause an eruption when they rise to the surface – exert the greatest pressure. The seismic waves add to this pressure, causing even more disturbance,” Brenguier says.

The magnitude 6.4 quake that occurred four days after the tsunami, followed by many smaller aftershocks, was a further indication that Mount Fuji is under high pressure.

So should Japan be on red alert? “We cannot establish a direct relation of cause and effect between quakes and volcanic eruptions, even if statistically the former lead to an increase in the latter,” Brenguier says. “All we can say is that Mount Fuji is now in a state of pressure, which means it displays a high potential for eruption. The risk is clearly higher.”

Science, however, has no way of predicting when this might happen. But there is a precedent. The last eruption of Mount Fuji occurred in 1707. It projected almost a billion cubic metres of ash and debris into the atmosphere, some of which reached Tokyo (then called Edo) 100km away. It was preceded, 49 days earlier, by a magnitude 8.7 quake to the south of Japan that, in conjunction with the tidal wave it raised, claimed more than 5,000 lives. This time, more than three years have already passed since the Tohoku quake. But that does not mean that Mount Fuji, under the constant supervision of Japanese geologists, is slumbering.

Come what may, the method developed by the Franco-Japanese team for investigating volcanic areas should improve the accuracy of efforts all over the world to assess the risk of major volcanic eruptions.

This story appeared in Guardian Weekly, which incorporates material from Le Monde

Note : The above story is based on materials provided by Pierre Le Hir “Guardian Weekly”

Catastrophic debris avalanches: A second volcanic hazard

Location map of the Taranaki peninsula and distribution of debris avalanche deposits surrounding Taranaki volcano, New Zealand. Credit: Image courtesy of Geological Society of America

Volcanic hazards aren’t limited to eruptions. Debris avalanche landslides can also cause a great deal of damage and loss of life. Stratovolcanoes, with their steep, conical shapes made up of lava and unconsolidated mixed materials, can reach a critical point of instability when they overgrow their flanks. This leads to partial collapse, and the product of this slope failure is a large-scale, rapid mass movement known as a catastrophic landslide or debris avalanche.

In a matter of minutes, a debris avalanche can drastically modify the shape and nature of the surrounding landscape, covering extensive areas (in this case, up to 27 kilometers away) and changing the normal water drainage system of the region.

About 25 thousand years ago, the biggest slope failure event known at Taranaki volcano, New Zealand, resulted in the Pungarehu debris avalanche deposit (DAD). Initial collapse of the proto-Taranaki volcano occurred near the Last Glacial Maximum, with snow and ice cover and substantial groundwater present. The collapsing, sliding, large blocks of edifice material, known as “megaclasts,” were highly fractured by the landslide generation and the depressurization event, forming pervasive jigsaw textures.

This study by scientists from Brazil, Mexico, and New Zealand provides a textural analysis of the unique features of this landslide. The authors examine grain sizes, sedimentary structures, and microscopic particle attributes and provide new insights into debris avalanche transport and internal evolution processes.

Their findings help to explain the formation of the highly irregular topography of debris avalanche deposits, with chaotically distributed (and probably temporary) zones of shear developing where softer lithologies occur in a collapsing mass, thus leading to differential velocity profiles of portions of the flowing mass in vertical and horizontal planes.

The authors write that their goal is not only to provide new insight concerning the transport and emplacement mechanisms of Pungarehu DAD, but to also improve understanding giant debris avalanche deposits worldwide.

Note : The above story is based on materials provided by Geological Society of America.

Risk of earthquake increased for about half of US

This undated handout image provided by the US Geological Survey (USGS) shows an updated federal earthquake risk map. A new map dials up the shaking hazard just a bit for about half of the US and lowers it for nearly a quarter of the nation. The U.S. Geologic Survey updated Thursday its national seismic hazard maps for the first time since 2008, taking into account research from the devastating 2011 earthquake and tsunami off the Japanese coast and the surprise 2011 Virginia temblor. (AP Photo/USGS)

A new federal earthquake map dials up the shaking hazard just a bit for about half of the United States and lowers it for nearly a quarter of the nation.
The U.S. Geologic Survey updated Thursday its national seismic hazard maps for the first time since 2008, taking into account research from the devastating 2011 earthquake and tsunami off the Japanese coast and the surprise 2011 Virginia temblor.

Most of the changes are slight. Project chief Mark Petersen said parts of Washington, Oregon, Utah, Oklahoma, Colorado, Wyoming and Tennessee moved into the top two hazard zones.

Parts of 16 states have the highest risk for earthquakes: Alaska, Hawaii, California, Oregon, Washington, Nevada, Utah, Idaho, Montana, Wyoming, Missouri, Arkansas, Tennessee, Illinois, Kentucky and South Carolina.

This undated handout image provided by the US Geological Survey (USGS) shows where the earthquake hazard increased and decreased from 2008. Red/brown increased. Blue decreased. A new federal earthquake risk map dials up the shaking hazard just a bit for about half of the United States and lowers it for nearly a quarter of the nation. The U.S. Geologic Survey updated Thursday its national seismic hazard maps for the first time since 2008, taking into account research from the devastating 2011 earthquake and tsunami off the Japanese coast and the surprise 2011 Virginia temblor. (AP Photo/USGS)

Note : The above story is based on materials provided by © 2014 The Associated Press. All rights reserved.

A global view of oceanic phytoplankton

University of Maine oceanographer Ivona Cetinic is participating in a NASA project to advance space-based capabilities for monitoring microscopic plants that form the base of the marine food chain.

Phytoplankton—tiny ocean plants that absorb carbon dioxide and deliver oxygen to Earth’s atmosphere—are key to the planet’s health. And NASA wants a clear, global view of them.

NASA’s Ship-Aircraft Bio-Optical Research (SABOR) mission will bring together marine and atmospheric scientists to tackle optical issues associated with satellite observations of phytoplankton.

The goal is to better understand marine ecology and phytoplankton’s major role in the global cycling of atmospheric carbon between the ocean and the atmosphere.

“Teams involved in this project are working together to develop next-generation tools that will change forever how we study oceans,” says Cetinic, a research associate at UMaine’s Darling Marine Center (DMC) in Walpole, Maine.

“Methods that will be developed during this experiment are something like 3-D glasses. They will allow us to see more details on the surface of the ocean and to see deeper into the ocean, helping us learn more about carbon in the ocean—carbon that is fueling oceanic ecosystems, as well as the fisheries and aquaculture.”

Cetinic will be a chief scientist aboard RV Endeavor that departs July 18 from Narragansett, Rhode Island. She received $1,043,662 from NASA’s Ocean Biology and Biogeochemistry program for her part in the three-year project.

Cetinic’s crew, which includes Wayne Slade of Sequoia Scientific, Inc., Nicole Poulton of Bigelow Laboratory for Ocean Sciences and UMaine Ph.D. student Alison Chase, will analyze water samples for carbon, as well as pump seawater continuously through on-board instruments to measure how ocean particles, including phytoplankton, interact with light.

Chase, who recently earned her master’s in oceanography at UMaine, will blog about the experience at earthobservatory.nasa.gov/blogs/fromthefield.

Interim DMC director Mary Jane Perry, who is participating in another research cruise this summer, will be involved in future data analysis.

Mike Behrenfeld of Oregon State University also will be aboard Endeavor and he and his team will use a new technique to directly measure phytoplankton biomass and photosynthesis.

“The goal is to develop mathematical relationships that allow scientists to calculate the biomass of the phytoplankton from optical signals measured from space, and thus to be able to monitor how ocean phytoplankton change from year to year and figure out what causes these changes,” he says.

Another research team also will be aboard Endeavor, which for three weeks will cruise through a range of ecosystems between the East Coast and Bahamas.

Alex Gilerson of City College of New York will lead a crew that will operate an array of instruments, including an underwater video camera equipped with polarization vision. It will continuously measure key characteristics of the sky and the water.

The measurements taken from aboard the ship will provide an up-close perspective and validate measurements taken simultaneously by scientists in aircraft.

NASA’s UC-12 airborne laboratory, based at NASA’s Langley Research Center in Hampton, Virginia, will make coordinated science flights beginning July 20.

One obstacle in observing marine ecosystems from space is that atmospheric particles interfere with measurements. Brian Cairns of NASA’s Goddard Institute for Space Studies in New York will lead an aircraft team with a polarimeter instrument to address the issue.

From an altitude of about 30,000 feet, the instrument will measure properties of reflected light, including brightness and magnitude of polarization. These measurements will define the concentration, size, shape and composition of particles in the atmosphere.

Polarimeter measurements of reflected light should provide valuable context for data from another instrument on the UC-12 designed to reveal how plankton and optical properties vary with water depth.

Chris Hostetler of Langley is leading that group. He and others will test a prototype lidar (light detection and ranging) system—the High Spectral Resolution Lidar-1 (HSRL-1). A laser that will probe the ocean to a depth of about 160 feet should reveal how phytoplankton concentrations change with depth, along with the amount of light available for photosynthesis.

Phytoplankton largely drive the functioning of ocean ecosystems and knowledge of their vertical distribution is needed to understand their productivity. This knowledge will allow NASA scientists to improve satellite-based estimates of how much atmospheric carbon dioxide is absorbed by the ocean.

NASA satellites contributing to SABOR are the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO), which view clouds and tiny particles in Earth’s atmosphere, as well as the Terra and Aqua satellites, which measure atmospheric, land and marine processes.

Analysis of data collected from the ship, aircraft and satellites is expected to guide preparation for a new, advanced ocean satellite mission—Pre-Aerosol, Clouds, and ocean Ecosystem (PACE), according to NASA.

PACE will extend observations of ocean ecology, biogeochemical cycling and ocean productivity begun by NASA in the late 1970s with the Coastal Zone Color Scanner and continued with the Sea-viewing Wide Field-of-view-Sensor (SeaWiFS) and the Moderate Resolution Imaging Spectroradiometer (MODIS) instruments on Terra and Aqua.

Note : The above story is based on materials provided by University of Maine

66-yard crater appears in far northern Siberia

This frame grab made Wednesday, July 16, 2014, shows a crater, discovered recently in the Yamal Peninsula, in Yamalo-Nenets Autonomous Okrug, Russia. Russian scientists said Thursday July 17, 2014 that they believe the 60-meter wide crater, discovered recently in far northern Siberia, could be the result of changing temperatures in the region. Andrei Plekhanov, a senior researcher at the Scientific Research Center of the Arctic, traveled on Wednesday to the crater. Plekhanov said 80 percent of the crater appeared to be made up of ice and that there were no traces of an explosion, eliminating the possibility that a meteorite had struck the region. (AP Photo/Associated Press Television)

Russian scientists say they believe a 60-meter (66-yard) wide crater discovered recently in far northern Siberia could be the result of changing temperatures in the region.
Andrei Plekhanov, a senior researcher at the Scientific Research Center of the Arctic, told the AP Thursday that the crater was mostly likely the result of a “build-up of excessive pressure” underground due to rising temperatures in the region.

Plekhanov on Wednesday traveled to the crater, some 30 kilometers (18.64 miles) from the Bovanenkovo gas field in the far northern Yamal peninsula. He said 80 percent of the crater appeared to be made up of ice and that there were no traces of an explosion, eliminating the possibility that a meteorite had struck the region.

This frame grab made Wednesday, July 16, 2014, shows a crater, discovered recently in the Yamal Peninsula, in Yamalo-Nenets Autonomous Okrug, Russia. Russian scientists said Thursday July 17, 2014 that they believe a 60-meter wide crater, discovered recently in far northern Siberia, could be the result of changing temperatures in the region. Andrei Plekhanov, a senior researcher at the Scientific Research Center of the Arctic, traveled on Wednesday to the crater. Plekhanov said 80 percent of the crater appeared to be made up of ice and that there were no traces of an explosion, eliminating the possibility that a meteorite had struck the region. (AP Photo/Associated Press Television)
In this frame grab made Wednesday, July 16, 2014, Andrei Plekhanov, a senior researcher at the Scientific Research Center of the Arctic, stands at a crater, discovered recently in the Yamal Peninsula, in Yamalo-Nenets Autonomous Okrug, Russia. Russian scientists said Thursday july 17, 2014 that they believe a 60-meter wide crater, discovered recently in far northern Siberia, could be the result of changing temperatures in the region. Andrei Plekhanov said 80 percent of the crater appeared to be made up of ice and that there were no traces of an explosion, eliminating the possibility that a meteorite had struck the region. (AP Photo/Associated Press Television)

Note : The above story is based on materials provided by © 2014 The Associated Press. All rights reserved.

The bend in the Appalachian mountain chain is finally explained

A dense, underground block of volcanic rock (shown in red) helped shape the well-known bend in the Appalachian mountain range. Credit: Graphic by Michael Osadciw/University of Rochester.

The 1500 mile Appalachian mountain chain runs along a nearly straight line from Alabama to Newfoundland — except for a curious bend in Pennsylvania and New York State. Researchers from the College of New Jersey and the University of Rochester now know what caused that bend — a dense, underground block of rigid, volcanic rock forced the chain to shift eastward as it was forming millions of years ago.

According to Cindy Ebinger, a professor of earth and environmental sciences at the University of Rochester, scientists had previously known about the volcanic rock structure under the Appalachians. “What we didn’t understand was the size of the structure or its implications for mountain-building processes,” she said.

The findings have been published in the journal Earth and Planetary Science Letters.

When the North American and African continental plates collided more than 300 million years ago, the North American plate began folding and thrusting upwards as it was pushed westward into the dense underground rock structure — in what is now the northeastern United States. The dense rock created a barricade, forcing the Appalachian mountain range to spring up with its characteristic bend.

The research team — which also included Margaret Benoit, an associate professor of physics at the College of New Jersey, and graduate student Melanie Crampton at the College of New Jersey — studied data collected by the Earthscope project, which is funded by the National Science Foundation. Earthscope makes use of 136 GPS receivers and an array of 400 portable seismometers deployed in the northeast United States to measure ground movement.

Benoit and Ebinger also made use of the North American Gravity Database, a compilation of open-source data from the U.S., Canada, and Mexico. The database, started two decades ago, contains measurements of the gravitational pull over the North American terrain. Most people assume that gravity has a constant value, but when gravity is experimentally measured, it changes from place to place due to variations in the density and thickness of Earth’s rock layers. Certain parts of Earth are denser than others, causing the gravitational pull to be slightly greater in those places.

Data on the changes in gravitational pull and seismic velocity together allowed the researchers to determine the density of the underground structure and conclude that it is volcanic in origin, with dimensions of 450 kilometers by 100 kilometers. This information, along with data from the Earthscope project ultimately helped the researchers to model how the bend was formed.

Ebinger called the research project a “foundation study” that will improve scientists’ understanding of Earth’s underlying structures. As an example, Ebinger said their findings could provide useful information in the debate over hydraulic fracturing — popularly known is hydrofracking — in New York State.

Hydrofracking is a mining technique used to extract natural gas from deep in the Earth. It involves drilling horizontally into shale formations, then injecting the rock with sand, water, and a cocktail of chemicals to free the trapped gas for removal. The region just west of the Appalachian Basin — the Marcellus Shale formation — is rich in natural gas reserves and is being considered for development by drilling companies.

Note : The above story is based on materials provided by University of Rochester.

Geophysicists prep for massive ‘ultrasound’ of Mount St. Helens

Mount St. Helens. Credit: USGS

A small army of 75 geophysicists is set to converge on Mount St. Helens this weekend to begin final preparations for the equivalent of a combined ultrasound and CAT scan of the famous volcano’s internal plumbing. The ambitious project, a joint undertaking by Earth scientists at Rice University, the University of Washington, the University of Texas at El Paso and other institutions, requires placing more than 3,500 active seismological sensors and 23 seismic charges around the volcano over the next few days.
“Mount St. Helens and other volcanoes in the Cascade Range threaten urban centers from Vancouver to Portland, and we’d like to better understand their inner workings in order to better predict when they may erupt and how severe those eruptions are likely to be,” said Rice’s Alan Levander, the lead scientist for the experiment.

Levander, Rice’s Carey Croneis Professor of Earth Science, said the instruments will measure seismic waves generated by the detonation of charges in 23 boreholes that are each about 80 feet deep. Most of the detonations are scheduled in the evening on July 22-23, but Levander said area residents are unlikely to hear or feel them because of the depth of the boreholes and because the detonations will produce vibrations that approximate a magnitude 2 earthquake, which typically cannot be felt.

“Our shots will provide enough seismic energy to develop a clear picture of the mountain’s inner workings, but in most cases not enough to be felt and certainly no more than low-level seismic activity that occurs in the area on a weekly basis,” Levander said.

Levander said the detonations will take place in areas where the ground has already been disturbed, such as clear-cuts, quarries, gravel pits and garbage dumps.

Dozens of mostly student volunteers are expected to arrive Friday for two days of training about how to set up the 3,500 active seismic sensors that will gather the bulk of the experimental data.

“These sensors are basically a computer in a can with a small battery,” Levander said. “They’re about the size of a water bottle, but because of their limited power supply, we only have about two days to deploy the whole lot.”

He said the volunteers will also pick up all the active sensors—and the data they’ve collected—within a couple of days of the explosions. A few more detonations will occur on the evening of July 30. A rearrangement of part of the sensor network will accompany those tests.

The coming tests follow two years of detailed planning and are part of a four-year project called Imaging Magma Under St. Helens (iMUSH), which could bring improvements in volcanic monitoring and advance warning systems at Mount St. Helens and other volcanoes.

The work area for the tests extends from Mount Rainier on the north to the Columbia River on the south, and from Interstate 5 on the west to Mount Adams on the east. An advanced team of researchers has been in the area for weeks installing 70 passive seismographs. Levander said these instruments, which take several hours to set up and will be left in place for two years, are more sophisticated and sensitive than the active sensors.

“The active-source monitoring will provide very high-resolution images at a relatively shallow depth, while the passive experiment data will be at a lower resolution but will be at a much greater depth,” said Kenneth Creager, a University of Washington professor of Earth and space sciences who is leading the passive monitoring.

Having both sets of monitors recording data from the active-source detonations will help scientists have a much clearer idea of how the deeper, harder-to-see structure compares with better defined shallow structure, he said.

A third technique, magnetotelluric monitoring, which produces data based on fluctuations in Earth’s electromagnetic field, will also be used to image the subterranean structures.

Mount St. Helens was chosen for the study because it has been the most active volcano in the Cascade Range, erupting twice in the last 35 years, and is readily accessible for the researchers and their equipment, Levander said.

More information:
Realtime data feeds from the seismic testing will be available at: assets.pnsn.org/realtimeplots/

Note : The above story is based on materials provided by Rice University

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