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  • richardmitnick 3:31 pm on September 23, 2020 Permalink | Reply
    Tags: "Let them eat rocks", , Earth Observation, Scientists are installing sensors in the ground at five different sites to monitor microbes’ activity for the next five years., The sites have been chosen because they represent different ecosystems, , UC Riverside is leading an effort that could help ensure food security and improve the worst effects of climate change — by studying rock-eating bacteria and fungi.   

    From UC Riverside: “Let them eat rocks” 

    UC Riverside bloc

    From UC Riverside

    September 23, 2020

    Jules L Bernstein
    Senior Public Information Officer
    jules.bernstein@ucr.edu
    (951) 827-4580

    1
    Microscopy image of Tympanidaceae, a fungus found at a research sample site. (Danny Newman and Mia Maltz/UCR)

    UC Riverside is leading an effort that could help ensure food security and improve the worst effects of climate change — by studying rock-eating bacteria and fungi.

    These microbes break apart chemical bonds in deep underground layers of rocks, then die and release nutrients such as nitrogen and phosphorus into the soil. Aside from fertilizer, this is the main way soil obtains these nutrients, and agriculture is dependent on the process.

    “Despite how critical they are for food production, our general knowledge of microbes in soils is so lacking,” said Emma Aronson, associate professor of microbiology and plant pathology.

    A new $4.2 million National Science Foundation grant aims to close the gap in scientists’ understanding. It will enable scientists to install sensors in the ground at five different sites and monitor the microbes’ activity for the next five years.

    The sensors will measure, among other things, carbon dioxide concentration at these sites throughout the five years of the study. “We’ll be able to watch the microbes breathing deep in the soil,” Aronson said.

    2
    Bioinformatics specialist Keshav Arogyaswamy digging toward bedrock to sample deep soil microbes in California’s southern Sierra Nevada. Credit Emma Aronson/UCR.

    The sites have been chosen because they represent different ecosystems, including a location in Idaho, the Luquillo Experimental Forest in Puerto Rico, the Great Smoky Mountains in South Carolina, the Santa Catalina mountains in Arizona, and the southern Sierra Nevada in California.

    Aronson, principal investigator of the project, said her team’s preliminary studies revealed bacterial behavior they could not explain. They found greater changes in the bacteria the deeper they looked in the soils, but only in half of the locations they sampled. With the other half, the bacteria did not change with depth.

    “We want to understand why that is,” Aronson said. “How much is this driven by rock types at the different sites? What role does vegetation play? Why do they live where they do? This grant will help us answer questions like these that will then allow scientists to test for more applied uses.”

    One application of the research could include a tool to help trap carbon in the ground. Researchers may be able to identify some deep soil bacteria that are better at extracting nutrients from rocks than others. Those bacteria would allow plants to become larger and, if they have extra nutrients, take up more carbon that would otherwise end up in the atmosphere, trapping heat.

    Bacteria that encourage plant growth also offer the potential for increased agricultural yields, and more food, which is critical given the potential for decreased crop production as the climate changes.

    This project brings together a coalition of scientists to examine the Earth’s active outer layer known as the critical zone, which extends from the top of the tallest tree down to the microbes in the bedrock. Partnering institutions include UC Berkeley and UC Merced, as well as the University of Arizona, Idaho State University, Kansas University, and the University of New Hampshire.

    A chief benefit of the project is its interdisciplinary nature, allowing collaboration between microbiologists, ecologists, geoscientists, soil, and rock scientists.

    “We are all joining to do work that we can only do together,” Aronson said.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    UC Riverside Campus

    The University of California, Riverside is one of 10 universities within the prestigious University of California system, and the only UC located in Inland Southern California.

    Widely recognized as one of the most ethnically diverse research universities in the nation, UCR’s current enrollment is more than 21,000 students, with a goal of 25,000 students by 2020. The campus is in the midst of a tremendous growth spurt with new and remodeled facilities coming on-line on a regular basis.

    We are located approximately 50 miles east of downtown Los Angeles. UCR is also within easy driving distance of dozens of major cultural and recreational sites, as well as desert, mountain and coastal destinations.

     
  • richardmitnick 11:04 am on September 23, 2020 Permalink | Reply
    Tags: , Earth Observation, , , Fibre-​optic cables are emerging as a valuable tool for geoscientists and glaciologists.,   

    From ETH Zürich: “Thousands of seismometers on a single cable” 

    From ETH Zürich

    22.09.2020
    Peter Rüegg

    Fibre-​optic cables are emerging as a valuable tool for geoscientists and glaciologists. They offer a relatively inexpensive way of measuring even the tiniest glacial earthquakes – plus they can also be used to obtain more accurate images of the geological subsurface in earthquake-​prone megacities.

    1
    Project manager Fabian Walter (at rear) and his colleague Małgorzata Chmiel check if the cable is fully functional. (Photo: Wojciech Gajek.)

    Today’s fibre-​optic cables move data at tremendous speeds, enabling us to stream films and TV shows in HD or even 8K resolution. Modern telecommuters rely on these superfast broadband fibre-​optic networks – but optical fibres also lend themselves to more unusual applications. For example, operators of critical infrastructure have long used fibre-​optic cables to monitor their facilities. “The idea of using optical fibres for multiple purposes is nothing new,” says Andreas Fichtner, a professor of geophysics in the Department of Earth Sciences at ETH Zürich. Together with Fabian Walter, a professor at the Laboratory of Hydraulics, Hydrology and Glaciology (VAW), he is now exploring a new technique that could massively expand the potential applications of optical fibres. Working on the Rhône Glacier in the Swiss Alps, the two ETH professors are measuring tiny glacial earthquakes at a far greater resolution than ever before.

    Fichtner’s primary interest lies in the potential that fibre-​optic cables offer in seismology. As a glaciologist, Walter is determined to gain a better understanding of glacier movement and the associated seismic activity in the ice: “I’m particularly interested in tiny earthquakes that originate in the glacier bed.”

    High-​resolution measurements

    In late June 2020, the researchers laid a nine-​kilometre-long cable across the surface of the Rhône Glacier and connected it to a measuring instrument known as an interrogator. The researchers pitched their tents on the moraine and occupied them in week-​long shifts for two months. Each week, a team of two was on site to monitor the equipment, replace the mobile hard drives when they were full and keep the power generator running.

    The technique used by the researchers is relatively simple. Laser pulses of a specific wavelength are directed through the optical fibre in a continuous sequence. Any pressure or tension on the cable changes the pattern of the light waves that are scattered back towards the interrogator by tiny defects within the fibre. The interrogator measures the interference in the returning signals, enabling researchers to calculate where quakes occurred and how powerful they were. This can be determined at a very high spatial and temporal resolution. “You’re basically replacing thousands of seismometers with a single cable,” says Fichtner. Although the cable is less sensitive than a high-​quality seismometer, it has the major advantage of offering a huge number of measurement points.

    The quantity of data generated by this high-​resolution method is enormous. “Analysing it will be a tremendous job,” Fichtner says with a smile. “We will have to come up with methods to cope with the sheer quantity of data.” They expect the measurement campaign to produce around 20 terabytes of raw data – ten to 100 times more than they would collect by distributing ten seismometers across the glacier.

    Fichtner and Walter carried out their first tests with a short cable in the spring of 2019. These were presented in a scientific paper that recently appeared in the scientific journal Nature Communications. As well as confirming just how much potential their new technique has to offer, this paper also revealed that glacier quakes primarily occur in clusters, especially at the boundary between the ice and the glacier bed. Clusters of this kind would imply that the ice does not slide smoothly, but rather moves forward in a jerky motion. “That’s not what you would expect based on current theories,” explains Walter. “Glaciologists assumed that glaciers could slide because the glacier bed was well lubricated with meltwater.” Some of the mini quakes in the Rhône Glacier occur as often as once a second.

    “My new hypothesis is that the sliding motion of glaciers is comparable to that of tectonic plates,” adds Walter. Most of the quakes measured in the Rhône Glacier have a magnitude of −1 to −2. “That’s roughly equivalent to ice cracking when you skate on a frozen lake,” he says. “It’s not something that you can feel like a real earthquake.”

    In Antarctica, however, scientists have recorded glacial earthquakes with a magnitude of 3 to 4, and in one extreme case magnitude 7 (for comparison, the 2015 Gorkha quake in Nepal had a magnitude of 7.8). But there’s apparently one key difference: compared to conventional earthquakes, large-​magnitude glacial quakes unfold slowly and can last for several minutes. That makes them less destructive than earthquakes that are caused by tectonic plate movement.

    Fibre-​optic networks to boost earthquake preparedness

    Geophysicist Fichtner hopes to use fibre-​optic cables for more than just measuring glacial earthquakes. He envisions one day using the fibre-​optic networks in big cities to study the geological subsurface. Known as seismic tomography, this technique can be used to detect weak layers of rock and critical fractures. The goal is to map the subsurface by measuring the speed and duration of earthquake waves captured by fibre-​optic cables. This would allow scientists to better assess the risk of earthquakes. One option might be to harness the fibre-​optic networks of major conurbations that face significant danger from earthquakes, such as Istanbul, Athens and San Francisco.

    Fichtner demonstrated how this could work by carrying out a feasibility study in Bern. Together with the internet service provider Switch, he and his team measured human-​made seismic activity using a straight six-​kilometre-long fibre-​optic cable. “That’s equivalent to about 3,000 small seismometers. Setting up that many devices so close together is simply impossible,” says Fichtner.

    He set up the interrogator in the server room at the University of Bern. The data from the fibre-​optic cable ultimately allows the team to create a detailed map of the Bern subsurface. “The fibre geometry was very simple – that’s one reason why Bern was the ideal test site,” Fichtner reflects. Learning to harness even more complex fibre-​optic networks is simply a matter of time, plus the possibility of performing the necessary measurements in big cities.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    ETH Zurich campus
    ETH Zürich is one of the leading international universities for technology and the natural sciences. It is well known for its excellent education, ground-breaking fundamental research and for implementing its results directly into practice.

    Founded in 1855, ETH Zürich today has more than 18,500 students from over 110 countries, including 4,000 doctoral students. To researchers, it offers an inspiring working environment, to students, a comprehensive education.

    Twenty-one Nobel Laureates have studied, taught or conducted research at ETH Zürich, underlining the excellent reputation of the university.

     
  • richardmitnick 10:01 am on September 22, 2020 Permalink | Reply
    Tags: "Plans underway for new polar ice and snow topography mission", , Earth Observation, ESA/Airbus Copernicus Polar Ice and Snow Topography Altimeter CRISTAL Mission,   

    From European Space Agency – United Space in Europe: “Plans underway for new polar ice and snow topography mission” 

    ESA Space For Europe Banner

    From European Space Agency – United Space in Europe

    21/09/2020

    Monitoring the cryosphere is essential to fully assess, predict and adapt to climate variability and change. Given the importance of this fragile component of the Earth system, today ESA, along with Airbus Defence and Space and Thales Alenia Space, have signed a contract to develop the Copernicus Polar Ice and Snow Topography Altimeter mission, known as CRISTAL.

    ESA/Airbus Copernicus Polar Ice and Snow Topography Altimeter CRISTAL Mission depiction.

    With a launch planned in 2027, the CRISTAL mission will carry, for the first time on a polar mission, a dual-frequency radar altimeter, and microwave radiometer, that will measure and monitor sea-ice thickness, overlying snow depth and ice-sheet elevations.

    These data will support maritime operations in the polar oceans and contribute to a better understanding of climate processes. CRISTAL will also support applications related to coastal and inland waters, as well as providing observations of ocean topography.


    CRISTAL in action

    The mission will ensure the long-term continuation of radar altimetry ice elevation and topographic change records, following on from previous missions such as ESA’s Earth Explorer CryoSat mission and other heritage missions.

    With a contract secured worth € 300 million, Airbus Defence and Space has been selected to develop and build the new CRISTAL mission, while Thales Alenia Space has been chosen as the prime contractor to develop its Interferometric Radar Altimeter for Ice and Snow (IRIS).

    ESA’s Director of Earth Observation Programmes, Josef Aschbacher, says, “I am extremely pleased to have the contract signed so we can continue the development of this crucial mission. It will be critical in monitoring climate indicators, including the variability of Arctic sea ice, and ice sheet and ice cap melting.”

    The contract for CRISTAL is the second out of the six new high-priority candidate missions to be signed – after the Copernicus Carbon Dioxide Monitoring mission (CO2M) in late-July. The CRISTAL mission is part of the expansion of the Copernicus Space Component programme of ESA, in partnership with the European Commission.

    The European Copernicus flagship programme provides Earth observation and in situ data, as well as a broad range of services for environmental monitoring and protection, climate monitoring and natural disaster assessment to improve the quality of life of European citizens.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 8:03 am on September 22, 2020 Permalink | Reply
    Tags: , Earth Observation, Extreme warming events impact fisheries and economies; understanding processes beneath ocean surface is crucial for assessment and management., Ningaloo Niño, ,   

    From Woods Hole Oceanographic Institution: “Studies investigate marine heatwaves, shifting ocean currents” 

    From Woods Hole Oceanographic Institution

    September 21, 2020

    1
    An aerial view of Cape Range National Park and Ningaloo Reef off Western Australia. A marine heatwave in 2011 led to the first-recorded coral bleaching event at Ningaloo Reef, a World Heritage site, and also caused extensive loss of a nearby kelp forest. Photo by Darkydoors, Shutter Stock Images.

    Extreme warming events impact fisheries and economies; understanding processes beneath ocean surface is crucial for assessment and management.

    North America experienced a series of dangerous heatwaves during the summer of 2020, breaking records from coast to coast. In the ocean, extreme warming conditions are also becoming more frequent and intense. Two new studies from the Woods Hole Oceanographic Institution (WHOI) investigate marine heatwaves and currents at the edge of the continental shelf, which impact regional ocean circulation and marine life.

    In a paper published September 17 in the Journal of Climate, WHOI oceanographers and collaborators at the GEOMAR Helmholtz Centre for Ocean Research Kiel in Germany use a new model to understand how ocean processes affect marine heatwaves at depth off the west coast of Australia. Known as “Ningaloo Niño,” these extreme warming events have caused mass die-offs of marine organisms, coral bleaching, and potentially permanent ecosystem shifts, all of which impact fisheries and the economies that depend on them.

    “This area is a hotspot for increasing temperature and extreme events, with drastic impacts on regional marine species,” said lead author Svenja Ryan. “It’s important to understand where in the water column temperature and salinity changes are happening so you can determine how the ecosystem will be impacted.”

    For the first time in the Southern Indian Ocean, Ryan and her co-authors, WHOI physical oceanographers Caroline Ummenhofer and Glen Gawarkiewicz, showed that the effects of marine heatwaves extend to 300 meters or more below the surface along the entire west coast of Australia. They found that during La Niña years, the southward-flowing Leeuwin Current becomes stronger and is associated with warm temperature anomalies at greater depths. These conditions were observed during the 2011 marine heatwave that led to the first-recorded coral bleaching at Ningaloo Reef, a World Heritage site, and extensive loss of a nearby kelp forest. During El Niño periods, the temperature and salinity anomalies associated with marine heatwaves are limited to the ocean surface, showing that complex ocean processes play an important role in the depth-extent of extreme events.

    Ryan and her colleagues are using a similar modeling approach to study marine heatwaves in the Northwest Atlantic. “The challenge, wherever you go, is that marine heatwaves have so many drivers,” Ryan said. “Understanding different types of events and their associated depth structure is crucial for regional impact assessment and adaptation strategies, as well as for predicting potential changes in a future climate.”

    2
    A new global ocean model shows how ocean processes affect marine heatwaves at depth off the west coast of Australia. Here, a case study of a catastrophic “Ningaloo Niño” event demonstrates how a marine heatwave impacted seawater temperatures at depth during the 2011/2012 austral winter.

    While models allow scientists to understand and predict changes to large-scale ocean processes, these models rely on data collected in the field. In a study published Aug. 30, 2020, in the Journal of Geophysical Research: Oceans, lead author Jacob Forsyth made use of 25 years of oceanographic data collected by the container ship (CMV) Oleander on its weekly voyages between New Jersey and Bermuda. These measurements provide valuable insight into the Mid-Atlantic Bight Shelfbreak Jet, a cool-water current that flows south along the continental shelf from Labrador to Cape Hatteras.

    Forsyth, a graduate student in the MIT-WHOI Joint Program and his co-authors, Gawarkiewicz and WHOI physical oceanographer Magdalena Andres, noticed a distinct relationship between the current and changing sea temperatures. Not only does the Shelfbreak Jet change seasonally— slowing down considerably from winter to summer— they also found it had slowed by about 10 percent since data collection began in 1992. The slow-down of the jet is consistent with the long-term warming of the continental shelf.

    “The Shelfbreak Jet is associated with the upwelling of nutrients, which affects the productivity of fisheries,” said Gawarkiewicz. “As marine heatwaves become more frequent, we need to understand how that links to the jet.“

    3
    The Mid-Atlantic Bight Shelfbreak Jet, shown here as a thin orange arrow, is a cool-water current that flows south along the continental shelf from Labrador to Cape Hatteras. A WHOI study found that the current has slowed by 10% over the last 25 years, a change consistent with gradual warming of the waters on the continental shelf, and with potential implications for fisheries. Source: NOAA.

    Starting in 2000, researchers began to notice that eddies of warm, salty water breaking off the Gulf Stream— known as “warm core rings”— had nearly doubled in number off the New England Continental Shelf. Not only do these rings cause water temperature and salinity to increase, they push the Shelfbreak Jet towards shore, and sometimes entirely shut down or reverse the direction of its flow. The authors noted that shifting currents and temperatures on the continental shelf have already prompted changes in key New England fisheries: cold-loving lobster are slowly moving offshore, while shortfin squid are more commonly found closer to shore.

    “You could call it a ‘calamari comeback’, where some of these rings are coming onto the continental shelf packed with squid. Others have none,” said Gawarkiewicz. “Jacob’s work is an important step in unraveling this mystery and helping us predict how currents and shelf temperatures will respond to approaching rings.”

    The oceanographic data collected by the CMV Oleander are essential for understanding rapidly shifting dynamics in a complex system, said the co-authors. Previous studies rely on satellite data, which are limited to measurements of the ocean surface over a wide area. “Looking at the surface might not tell the whole story of what’s happening when rings approach the continental shelf, or their effects on upwelling,” said Forsyth. “This paper shows how important it is to have this type of long-term monitoring.”

    This research was funded by the National Science Foundation Division of Ocean Sciences, the Office of Naval Research, the Alexander von Humboldt Foundation, the WHOI Postdoctoral Scholar program, and the James E. and Barbara V. Moltz Fellowship for Climate-Related Research. Data collection via the CMV Oleander volunteer observing ship is made possible by the continued cooperation of Bermuda Container Line/Neptune Group Ltd.

    See the full article here .

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    Woods Hole Oceanographic Institute

    Vision & Mission

    The ocean is a defining feature of our planet and crucial to life on Earth, yet it remains one of the planet’s last unexplored frontiers. For this reason, WHOI scientists and engineers are committed to understanding all facets of the ocean as well as its complex connections with Earth’s atmosphere, land, ice, seafloor, and life—including humanity. This is essential not only to advance knowledge about our planet, but also to ensure society’s long-term welfare and to help guide human stewardship of the environment. WHOI researchers are also dedicated to training future generations of ocean science leaders, to providing unbiased information that informs public policy and decision-making, and to expanding public awareness about the importance of the global ocean and its resources.
    Mission Statement

    The Woods Hole Oceanographic Institution is dedicated to advancing knowledge of the ocean and its connection with the Earth system through a sustained commitment to excellence in science, engineering, and education, and to the application of this knowledge to problems facing society.

     
  • richardmitnick 4:44 pm on September 18, 2020 Permalink | Reply
    Tags: "Undersea Earthquakes Shake Up Climate Science", , As much as 95 percent of the extra heat trapped on Earth by greenhouse gases is held in the world's oceans., , Climate Science, Earth Observation, , Listening for the sounds from the many earthquakes that regularly occur under the ocean., Monitoring the temperature of ocean waters has been a priority for climate scientists., Now Caltech researchers have discovered that seismic rumblings on the seafloor can provide them with another tool for doing that., The speed of sound in water increases as the water's temperature rises., These sound waves in the ocean can be clearly recorded by seismometers.   

    From Caltech: “Undersea Earthquakes Shake Up Climate Science” 

    Caltech Logo

    From Caltech

    September 18, 2020
    Emily Velasco
    626‑395‑6487
    evelasco@caltech.edu

    1
    Image Credit : Caltech

    Despite climate change being most obvious to people as unseasonably warm winter days or melting glaciers, as much as 95 percent of the extra heat trapped on Earth by greenhouse gases is held in the world’s oceans. For that reason, monitoring the temperature of ocean waters has been a priority for climate scientists, and now Caltech researchers have discovered that seismic rumblings on the seafloor can provide them with another tool for doing that.

    In a new paper publishing in Science, the researchers show how they are able to make use of existing seismic monitoring equipment, as well as historic seismic data, to determine how much the temperature of the earth’s oceans has changed and continues changing, even at depths that are normally out of the reach of conventional tools.

    They do this by listening for the sounds from the many earthquakes that regularly occur under the ocean, says Jörn Callies, assistant professor of environmental science and engineering at Caltech and study co-author. Callies says these earthquake sounds are powerful and travel long distances through the ocean without significantly weakening, which makes them easy to monitor.

    Wenbo Wu, postdoctoral scholar in geophysics and lead author of the paper, explains that when an earthquake happens under the ocean, most of its energy travels through the earth, but a portion of that energy is transmitted into the water as sound. These sound waves propagate outward from the quake’s epicenter just like seismic waves that travel through the ground, but the sound waves move at a much slower speed. As a result, ground waves will arrive at a seismic monitoring station first, followed by the sound waves, which will appear as a secondary signal of the same event. The effect is roughly similar to how you can often see the flash from lightning seconds before you hear its thunder.

    “These sound waves in the ocean can be clearly recorded by seismometers at a much longer distance than thunder — from thousands of kilometers away,” Wu says. “Interestingly, they are even ‘louder’ than the vibrations traveling deep in the solid Earth, which are more widely used by seismologists.”

    The speed of sound in water increases as the water’s temperature rises, so, the team realized, the length of time it takes a sound to travel a given distance in the ocean can be used to deduce the water’s temperature.

    “The key is that we use repeating earthquakes—earthquakes that happen again and again in the same place,” he says. “In this example we’re looking at earthquakes that occur off Sumatra in Indonesia, and we measure when they arrive in the central Indian ocean. It takes about a half hour for them to travel that distance, with water temperature causing about one-tenth-of-a second difference. It’s a very small fractional change, but we can measure it.”

    Wu adds that because they are using a seismometer that has been in the same location in the central Indian Ocean since 2004, they can look back at the data it collected each time an earthquake occurred in Sumatra, for example, and thus determine the temperature of the ocean at that same time.

    “We are using small earthquakes that are too small to cause any damage or even be felt by humans at all,” Wu says. “But the seismometer can detect them from great distances , thus allowing us to monitor large-scale ocean temperature changes on a particular path in one measurement.”

    Callies says the data they have analyzed confirm that the Indian Ocean has been warming, as other data collected through other methods have indicated, but that it might be warming even faster than previously estimated.

    “The ocean plays a key role in the rate that the climate is changing,” he says. “The ocean is the main reservoir of energy in the climate system, and the deep ocean in particular is important to monitor. One advantage of our method is that the sound waves sample depths below 2,000 meters, where there are very few conventional measurements.”

    Depending on which set of previous data they compare their results to, ocean warming appears to be as much as 69 percent greater than had been believed. However, Callies cautions against drawing any immediate conclusions, as more data need to be collected and analyzed.

    Because undersea earthquakes happen all over the world, Callies says it should be possible to expand the system he and his fellow researchers developed so that it can monitor water temperatures in all of the oceans. Wu adds that because the technique makes use of existing infrastructure and equipment, it is relatively low-cost.

    “We think we can do this in a lot of other regions,” Callies says. “And by doing this, we hope to contribute to the data about how our oceans are warming.”

    See the full article here .


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    Please help promote STEM in your local schools.


    Stem Education Coalition

    The California Institute of Technology (commonly referred to as Caltech) is a private research university located in Pasadena, California, United States. Caltech has six academic divisions with strong emphases on science and engineering. Its 124-acre (50 ha) primary campus is located approximately 11 mi (18 km) northeast of downtown Los Angeles. “The mission of the California Institute of Technology is to expand human knowledge and benefit society through research integrated with education. We investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

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  • richardmitnick 9:10 am on September 18, 2020 Permalink | Reply
    Tags: , Earth Observation, , Metal-mesh antenna reflector   

    From European Space Agency – United Space in Europe: “Mesh reflector for shaped radio beams” 

    ESA Space For Europe Banner

    From European Space Agency – United Space in Europe

    17/09/2020

    1

    This prototype 2.6-m diameter metal-mesh antenna reflector represents a big step forward for the European space sector: versions can be manufactured to reproduce any surface pattern that antenna designers wish, something that was previously possible only with traditional solid antennas.

    “This is really a first for Europe,” says ESA antenna engineer Jean-Christophe Angevain. “China and the US have also been working hard on similar shaped mesh reflector technology. It is needed so that sufficiently large antennas can be deployed in orbit, which would otherwise be too bulky to fit inside a launcher fairing, while also meeting required performance levels.”

    ESA’s AMPER (Advanced techniques for mesh reflector with improved radiation pattern performance) project performed with Large Space Structures GmbH in Germany as prime and TICRA in Denmark as subcontractor.

    Antenna reflectors for satellites are often surprisingly ‘lumpy’ looking. Their basic paraboloid convex shape is distorted with additional peaks and valleys. These serve to contour the resulting radio frequency beam, typically to boost signal gain over target countries and minimise it beyond their borders.

    “This tailored surface shaping is traditionally done with traditional metal or carbon fibre reinforced plastic composite reflectors,” adds Jean-Christophe. “The challenge was how to reproduce such shaping using a mesh reflector design. The obvious solution would have been a conventional tension truss double layer solution, with the mesh held together tautly on an alternating ‘push and ‘pull’ basis. A smart alternative solution has been proposed and followed by the team.”

    Leri Datashvili, CEO and Chief Designer of Large Space Structures explains: “The design of our shaped mesh reflector is based on tension members supported by a peripheral truss structure which enables decoupling of the shaped surface and the structure. Therefore, the design can be implemented for any size of reflector, for any frequencies ranging from P-band to Ka-band. Furthermore, either deployable or fixed reflector technology can be realised.”

    “This 2.6-m ‘breadboard’ prototype proves the concept at C-band frequency, and the RF measurements have shown good correlation with radio-frequency and mechanical predictions” adds Jean-Christophe.

    The AMPER project was supported through ESA’s Technology Development Element, with prototype testing carried out in ESA’s Hertz chamber at its ESTEC technical centre in the Netherlands. As a next step the AMPER team plan to produce a deployable version, aimed at Earth observation as well as telecommunications uses.

    Meanwhile this prototype reflector will be on show during next month’s virtual ESA Open Day at ESTEC.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 5:48 pm on September 16, 2020 Permalink | Reply
    Tags: "Seismic Monitoring May Improve Early Warnings for Glacial Lake Outburst Floods", , Columbia University – Earth Institute, Earth Observation, Glacial lake outburst floods are becoming more frequent and more destructive in mountainous areas.   

    From Columbia University – Earth Institute: “Seismic Monitoring May Improve Early Warnings for Glacial Lake Outburst Floods” 

    Columbia U bloc

    From Columbia University – Earth Institute

    September 16, 2020
    Sarah Fecht
    Ben Orlove

    Vibrations in the ground may help to improve advanced warnings about sudden floods that result from glacial melting, according to a study published today in Science Advances.

    On October 7, 1994, a natural dam that had been holding back a glacial lake burst, sending floodwaters crashing downstream into the Bhutanese village of Punakha. The sudden flood killed 21 people, destroyed 816 acres of crops and 6 tons of stored food, and washed away homes and other infrastructure. The new study, led by researchers at Columbia University’s Lamont-Doherty Earth Observatory, discovered that local seismic devices unknowingly recorded this glacial lake outburst flood five hours before it reached the village.

    1
    The larger map (A) shows the Pho Chhu river as it flows from the Himalayas into the Bay of Bengal. Seismometer locations are marked with yellow dots. The inset (B) zooms in on the area inside the red box in A, indicating the area where the glacial lake outburst flood began and the location of the village of Punakha 90 kilometers downstream. Image: Maurer et al./Science Advances 2020

    Glacial lake outburst floods are becoming more frequent and more destructive in mountainous areas. As glaciers melt, the water pools into lakes trapped behind dams made of rocky glacial debris and ice jams. When the dam shifts or too much pressure builds behind it, the lake water rushes out in a catastrophic burst, posing a danger to downstream communities. As the planet warms, glacial lakes are becoming larger and more common, thus increasing the potential for glacial lake outburst floods (GLOFs).

    In the study, led by Lamont-Doherty graduate student Josh Maurer, researchers discovered that a seismometer array located about 100 kilometers from the glacial lake had recorded a clear high-frequency signal at approximately 1:45am, around the time that the dam would have burst. They hypothesize that as the dam ruptured, the powerful and sudden outflow of water and/or sediments struck the riverbed, causing the vibrations that were picked up by the seismometers. The team was able to use the seismic data to reconstruct the flood as it made its way 90 kilometers downstream, reaching the village of Punakha at around 7am.

    2
    The tremors triggered by the GLOF and detected by far away seismometers: the initial outburst at 1:45 a.m., flood getting stronger at 2:15 a.m., and slowly tapering off after 7:15 a.m. Image: Maurer et al./Science Advances 2020

    Currently, instruments monitor local water level in some glacial lakes and alert local communities if the lake level suddenly drops, indicating a GLOF. However, such systems are known to be somewhat unreliable and have issued false alarms in the past. The study authors suggest that with some refinement, real-time seismic monitoring could be combined with water level monitoring systems to minimize false alarms and maximize warning times. In addition, a few strategically placed seismic sensors could potentially monitor for GLOFs over a large area, whereas water level monitors must be installed lake by lake.

    The authors note that more research is needed before seismic GLOF monitors would be ready for deployment. The team hopes to find and explore other instances where seismometers have captured GLOF events, to better understand how to read and analyze the signals in real time. They also caution that the Punakha flood was very large, so the signal stood out clearly in the data; in the future, they hope to better understand whether the technique can reliably detect smaller glacial lake outburst floods, which can still cause severe damage.

    By reconstructing the Punakha flood, the researchers were also able to test various models of how flood waters would be expected to flow through the area, showing that seismic data could help to improve flood modeling. In addition, the paper used satellite imagery before and after the GLOF to assess its impacts on the area.

    Experts who were not involved in the study, including geographer Simon Allen and glaciologist Holger Frey (both from the University of Zürich), said the study represents a promising first step toward a seismology-based early warning system. Allen said that more research is needed, since the technique has only been tested on one lake so far, and cautioned that maintaining a real-time seismic monitoring network in the Himalayas or elsewhere would present financial and technical challenges.

    “The algorithms need to be extremely reliable,” said Frey. “All events must be detected, but at the same time false alarms need to be avoided by all means.” He also emphasized that including people from the affected communities in the design and implementation of such systems is critical in determining whether or not they are ultimately successful.

    “This study is a great demonstration of the potential for long-range seismic detection of large outburst floods,” said Kristen Cook, a geologist at the GFZ German Research Centre for Geosciences who was not involved in the study. “This seismic detection could have important implications looking both back in time to validate flood models and better understand the processes of outburst floods, and potentially forwards in time if a seismic early warning system can be developed. Outburst floods are a big concern in the Himalaya, especially as development along river corridors increases and lakes are growing, so both more robust early warning and better modeling would have significant societal benefits.”

    Other authors of the study include: Joerg Schaefer, Joshua Russell, and Nicolas Young from Columbia University; Summer Burton Rupper from the University of Utah; Norbu Wangdi from the Center for Water, Climate, and Environmental Policy in Bhutan; and Aaron Putnam from the University of Maine.

    Learn more about the study in a brief Q&A with study co-author Joerg Schaefer, below.

    How did the idea for this study first develop?

    This all started when we were working on the well-preserved and nearly complete moraine sequences in front of the GLOF lakes. They were in the pathway of the 1994 GLOF, and beryllium dating shows that they are old, like 4,000 years old. I was puzzled as to how such a devastating GLOF could pass these old glacial landforms without destroying them, washing them out. I asked graduate student Josh Maurer to check the spy satellite imagery and the subsequent remote sensing images for pictures of the lakes and moraines just before and just after the flood. He did that, and we documented the outburst and early phase of the 1994 GLOF. We learned that the flood was just not super dramatic right at the start, and only took out a small part of the terminal moraine section. This is a striking and scary reminder that GLOFs starting at these high altitudes pick up their devastating energy by gravity on their way downhill.

    Josh realized the potential, and we started to wonder if the GLOF signal should not be visible in the seismometer record. Josh got in touch with Josh Russell, a PhD student in seismology at Lamont, and together they went to work and applied a technique called ‘cross-correlation based seismic analyses,’ with which they could track the evolution of the GLOF with seismometers as far as 100 km away from the actual flood. They found the flood signal in stunning clarity and synthesized the seismic data with eyewitness reports and a downstream gauge station within a numerical flood model.

    We also used the remote imagery before and after the flood to estimate the sediment deposition in the valley downstream to assess the damage, and traced the speed of vegetation recovery.

    This is probably the most innovative earth science paper I have had the pleasure to be part of. My main role in it has been to support the work of these brilliant grad students.

    Did you encounter any obstacles in the development of this project? If so, what were they? How did you overcome them?

    Josh and Josh encountered a variety of problems during their cross-correlation analyses, but they worked brilliantly and effectively as a team. Once all the results were on the table, it took us a while to organize the pieces from many different disciplines to form a coherent earth science manuscript, and to realize and formulate the potential of this technique for a new generation of GLOF early warning systems.

    How do you think other glacial lakes could be prioritized for future research along these lines?

    One of the biggest strengths of this approach is the regional applicability. We can use this toolkit, for example, to ask the seismometer record whether or not there are similar ‘GLOF-type signals’ in the system. And, using Josh’s satellite image processing techniques, we can search the region for the source of similar floods that might have occurred in the area over the last 40 years.

    Being able to track the formation, growth and in particular increase in lake level over time is the key to evaluate and identify the most hazardous lakes in the region. Topography and sediment availability are probably similar across different GLOF-prone valleys in the region, but we should absolutely produce a map highlighting human settlements and areas that are key to their livelihoods in relation to the GLOF hazard from higher up in the Himalayas.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Columbia’s Earth Institute blends research in the physical and social sciences, education and practical solutions to help guide the world onto a path toward sustainability.

    Two central ideas led to the creation of the Earth Institute in 1995. The first was to advance the basic understanding of earth science. The second was to apply that knowledge to decisions made by governments and businesses around the world. In the ensuing years, we have created a new kind of academic institution: a community of environmental and social scientists, lawyers, policy and management analysts, health experts and engineers who collaborate across schools and disciplines. Today, the Earth Institute has become a world leader in the basic and applied knowledge required to achieve sustainability.

    Columbia University Campus

    Columbia University was founded in 1754 as King’s College by royal charter of King George II of England. It is the oldest institution of higher learning in the state of New York and the fifth oldest in the United States.

     
  • richardmitnick 12:49 pm on September 15, 2020 Permalink | Reply
    Tags: "Dams Alter Nutrient Flows to Coasts", , Changing nutrient loads may adversely affect coastal ecosystems., Earth Observation,   

    From Eos: “Dams Alter Nutrient Flows to Coasts” 

    From AGU
    Eos news bloc

    From Eos

    9.15.20
    Elizabeth Thompson

    New models indicate how dams worldwide influence the mix of nutrients in river water reaching the ocean. As more dams are built, changing nutrient loads may adversely affect coastal ecosystems.

    1
    Commercial operation of the Huanza hydroelectric dam near Lima, Peru, began in 2014. Credit: tuproyecto, CC 0.

    The right balance of nutrients is crucial for a healthy coastal ecosystem. If rivers deposit too much nitrogen and phosphorus in coastal areas, algae that flourish on those nutrients can cause dead zones; if too little silicon flows downstream, organisms that depend on it will die off. Human interventions, whether through the addition of nutrients or through direct alteration of river flows, tend to upset natural nutrient balances. In a new study, Maavara et al. [Geophysical Research Letters] modeled how dams affect ratios of nitrogen, phosphorus, and silicon in coastal waters around the world.

    The researchers found that dams withhold algae-fertilizing nutrients at different rates. For example, nitrogen-to-phosphorus ratios in river water reaching the ocean tend to increase because dam reservoirs remove phosphorus more efficiently. However, if human-generated nitrogen emissions are better controlled in coming years, this trend will reverse, and more phosphorus will flow to the coasts instead, according to the team’s models.

    Over time, changes in land use and dam construction may lead to shortages of silicon in discharged water. By 2030, dams could interrupt up to 93% of Earth’s river systems, and most new dams will be hydroelectric dams. Rather than holding back large volumes of water, these dams capture energy as water flows through them. With the long water storage periods of older dams, phosphorus is removed more efficiently than nitrogen or silicon is. However, with shorter flow delays, more silicon is lost, meaning that water reaching the coasts has less silicon relative to nitrogen and phosphorus.

    Marine diatoms, which depend on silicon, are responsible for up to 40% of primary production in oceans. When fewer diatoms occupy coastal regions because of silicon shortages, other algae species take up available nutrients and can cause toxic algal blooms.

    The models predict substantial changes in river-borne nutrient loads in the coming decades, including increasing silicon limitation, in areas where dam building is progressing quickly, such as Southeast Asia, South America, and parts of Africa. But nutrient ratios and how they will change ultimately depend on land use around rivers. The researchers noted that as the effects of dams vary by nutrient and over time, more detailed models are needed to further explore future nutrient relationships along coasts.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Eos is the leading source for trustworthy news and perspectives about the Earth and space sciences and their impact. Its namesake is Eos, the Greek goddess of the dawn, who represents the light shed on understanding our planet and its environment in space by the Earth and space sciences.

     
  • richardmitnick 10:35 am on September 15, 2020 Permalink | Reply
    Tags: "Meteorite strikes may create unexpected form of silica", , , , , Earth Observation,   

    From Carnegie Institution for Science: “Meteorite strikes may create unexpected form of silica” 

    Carnegie Institution for Science
    From Carnegie Institution for Science

    August 26, 2020

    1
    A photograph of a meteorite strike site in Coconino County, Arizona. New work from Carnegie’s Sally June Tracy and collaborators Stefan Turneaure of Washington State University and Thomas Duffy of Princeton University reveals an unexpected new form of silica created in the type of extreme conditions caused by an impact. Image is courtesy of Shutterstock.

    2
    X-ray diffraction images showing the new form of silica created by sending an intense shock wave through a sample of quartz using a specialized gas gun. When the x-rays bounce off repeating planes of a crystalline structure, they scatter. This creates a distinctive ring pattern. Each ring is associated with a different plane and together this data can tell researchers about the material’s atomic-level architecture. Image is courtesy of Sally June Tracy, Stefan Turneaure, and Thomas Duffy.

    When a meteorite hurtles through the atmosphere and crashes to Earth, how does its violent impact alter the minerals found at the landing site? What can the short-lived chemical phases created by these extreme impacts teach scientists about the minerals existing at the high-temperature and pressure conditions found deep inside the planet?

    New work led by Carnegie’s Sally June Tracy examined the crystal structure of the silica mineral quartz under shock compression and is challenging longstanding assumptions about how this ubiquitous material behaves under such intense conditions. The results are published in Science Advances.

    “Quartz is one of the most abundant minerals in Earth’s crust, found in a multitude of different rock types,” Tracy explained. “In the lab, we can mimic a meteorite impact and see what happens.”

    Tracy and her colleagues—Washington State University’s (WSU) Stefan Turneaure and Princeton University’s Thomas Duffy, a former Carnegie Fellow—used specialized impact facilities to accelerate projectiles into quartz samples at extremely high speeds—several times faster than a bullet fired from a rifle. Special x-ray instruments were used to discern the crystal structure of the material that forms less than one-millionth of a second after impact. Experiments were carried out at the Dynamic Compression Sector (DCS), which is operated by WSU and located at the Advanced Photon Source, Argonne National Laboratory.

    Quartz is made up of one silicon atom and two oxygen atoms arranged in a tetrahedral lattice structure. Because these elements are also common in the silicate-rich mantle of the Earth, discovering the changes quartz undergoes at high-pressure and -temperature conditions, like those found in the Earth’s interior, could also reveal details about the planet’s geologic history.

    When a material is subjected to extreme pressures and temperatures, its internal atomic structure can be re-shaped, causing its properties to shift. For example, both graphite and diamond are made from carbon. But graphite, which forms at low pressure, is soft and opaque, and diamond, which forms at high pressure, is super-hard and transparent. The different arrangements of carbon atoms determine their structures and their properties, and that in turn affects how we engage with and use them.

    Despite decades of research, there has been a long-standing debate in the scientific community about what form silica would take during an impact event, or under dynamic compression conditions such as those deployed by Tracy and her collaborators. Under shock loading, silica is often assumed to transform to a dense crystalline form known as stishovite—a structure believed to exist in the deep Earth. Others have argued that because of the fast timescale of the shock the material will instead adopt a dense, glassy structure.

    Tracy and her team were able to demonstrate that counter to expectations, when subjected to a dynamic shock of greater than 300,000 times normal atmospheric pressure, quartz undergoes a transition to a novel disordered crystalline phase, whose structure is intermediate between fully crystalline stishovite and a fully disordered glass. However, the new structure cannot last once the burst of intense pressure has subsided.

    “Dynamic compression experiments allowed us to put this longstanding debate to bed,” Tracy concluded. “What’s more, impact events are an important part of understanding planetary formation and evolution and continued investigations can reveal new information about these processes.”

    This work is based on experiments performed at the Dynamic Compression Sector, operated by WSU under a DOE/ NNSA award. This research used the resources of the Advanced Photon Source, a Department of Energy Office of Science User Facility operated for the DOE Office of Science by the Argonne National Laboratory.


    ANL Advanced Photon Source.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Carnegie Institution of Washington Bldg

    Carnegie Institution for Science

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    Carnegie 6.5 meter Magellan Baade and Clay Telescopes located at Carnegie’s Las Campanas Observatory, Chile. over 2,500 m (8,200 ft) high.


    Carnegie Las Campanas 2.5 meter Irénée Dupont telescope, Atacama Desert, over 2,500 m (8,200 ft) high approximately 100 kilometres (62 mi) northeast of the city of La Serena,Chile.

    Carnegie Institution 1-meter Swope telescope at Las Campanas, Chile, 100 kilometres (62 mi) northeast of the city of La Serena, near the north end of a 7 km (4.3 mi) long mountain ridge, Cerro Las Campanas, near the southern end and over 2,500 m (8,200 ft) high, at Las Campanas, Chile.

     
  • richardmitnick 7:39 am on September 12, 2020 Permalink | Reply
    Tags: "High-fidelity record of Earth’s climate history puts current changes in context", , , Earth Observation, For the first time climate scientists have compiled a continuous high-fidelity record of variations in Earth’s climate extending 66 million years into the past., , Greenhouse gas emissions and other human activities are now driving the planet toward the Warmhouse and Hothouse climate states not seen since the Eocene epoch., The climate shows rhythmic variations corresponding to changes in Earth’s orbit around the sun., The new climate record provides a valuable framework for many areas of research., The record reveals four distinctive climate states which the researchers dubbed Hothouse; Warmhouse; Coolhouse; and Icehouse.,   

    From UC Santa Cruz: “High-fidelity record of Earth’s climate history puts current changes in context” 


    From UC Santa Cruz

    September 10, 2020
    Tim Stephens
    stephens@ucsc.edu

    A continuous record of the past 66 million years shows natural climate variability due to changes in Earth’s orbit around the sun is much smaller than projected future warming due to greenhouse gas emissions.

    1

    For the first time, climate scientists have compiled a continuous, high-fidelity record of variations in Earth’s climate extending 66 million years into the past. The record reveals four distinctive climate states, which the researchers dubbed Hothouse, Warmhouse, Coolhouse, and Icehouse.

    These major climate states persisted for millions and sometimes tens of millions of years, and within each one the climate shows rhythmic variations corresponding to changes in Earth’s orbit around the sun. But each climate state has a distinctive response to orbital variations, which drive relatively small changes in global temperatures compared with the dramatic shifts between different climate states.

    The new findings, published September 10 in Science, are the result of decades of work and a large international collaboration. The challenge was to determine past climate variations on a time scale fine enough to see the variability attributable to orbital variations (in the eccentricity of Earth’s orbit around the sun and the precession and tilt of its rotational axis).

    “We’ve known for a long time that the glacial-interglacial cycles are paced by changes in Earth’s orbit, which alter the amount of solar energy reaching Earth’s surface, and astronomers have been computing these orbital variations back in time,” explained coauthor James Zachos, distinguished professor of Earth and planetary sciences and Ida Benson Lynn Professor of Ocean Health at UC Santa Cruz.

    “As we reconstructed past climates, we could see long-term coarse changes quite well. We also knew there should be finer-scale rhythmic variability due to orbital variations, but for a long time it was considered impossible to recover that signal,” Zachos said. “Now that we have succeeded in capturing the natural climate variability, we can see that the projected anthropogenic warming will be much greater than that.”

    Icehouse

    For the past 3 million years, Earth’s climate has been in an Icehouse state characterized by alternating glacial and interglacial periods. Modern humans evolved during this time, but greenhouse gas emissions and other human activities are now driving the planet toward the Warmhouse and Hothouse climate states not seen since the Eocene epoch, which ended about 34 million years ago. During the early Eocene, there were no polar ice caps, and average global temperatures were 9 to 14 degrees Celsius higher than today.

    “The IPCC projections for 2300 in the ‘business-as-usual’ scenario will potentially bring global temperature to a level the planet has not seen in 50 million years,” Zachos said.

    Critical to compiling the new climate record was getting high-quality sediment cores from deep ocean basins through the international Ocean Drilling Program (ODP, later the Integrated Ocean Drilling Program, IODP, succeeded in 2013 by the International Ocean Discovery Program). Signatures of past climates are recorded in the shells of microscopic plankton (called foraminifera) preserved in the seafloor sediments. After analyzing the sediment cores, researchers then had to develop an “astrochronology” by matching the climate variations recorded in sediment layers with variations in Earth’s orbit (known as Milankovitch cycles).

    “The community figured out how to extend this strategy to older time intervals in the mid-1990s,” said Zachos, who led a study published in 2001 in Science that showed the climate response to orbital variations for a 5-million-year period covering the transition from the Oligocene epoch to the Miocene, about 25 million years ago.

    “That changed everything, because if we could do that, we knew we could go all the way back to maybe 66 million years ago and put these transient events and major transitions in Earth’s climate in the context of orbital-scale variations,” he said.

    Sediment cores

    Zachos has collaborated for years with lead author Thomas Westerhold at the University of Bremen Center for Marine Environmental Sciences (MARUM) in Germany, which houses a vast repository of sediment cores. The Bremen lab along with Zachos’s group at UCSC generated much of the new data for the older part of the record.

    Westerhold oversaw a critical step, splicing together overlapping segments of the climate record obtained from sediment cores from different parts of the world. “It’s a tedious process to assemble this long megasplice of climate records, and we also wanted to replicate the records with separate sediment cores to verify the signals, so this was a big effort of the international community working together,” Zachos said.

    Now that they have compiled a continuous, astronomically dated climate record of the past 66 million years, the researchers can see that the climate’s response to orbital variations depends on factors such as greenhouse gas levels and the extent of polar ice sheets.

    “In an extreme greenhouse world with no ice, there won’t be any feedbacks involving the ice sheets, and that changes the dynamics of the climate,” Zachos explained.

    Greenhouse gas levels

    Most of the major climate transitions in the past 66 million years have been associated with changes in greenhouse gas levels. Zachos has done extensive research on the Paleocene-Eocene Thermal Maximum (PETM), for example, showing that this episode of rapid global warming, which drove the climate into a Hothouse state, was associated with a massive release of carbon into the atmosphere. Similarly, in the late Eocene, as atmospheric carbon dioxide levels were dropping, ice sheets began to form in Antarctica and the climate transitioned to a Coolhouse state.

    “The climate can become unstable when it’s nearing one of these transitions, and we see more deterministic responses to orbital forcing, so that’s something we would like to better understand,” Zachos said.

    The new climate record provides a valuable framework for many areas of research, he added. It is not only useful for testing climate models, but also for geophysicists studying different aspects of Earth dynamics and paleontologists studying how changing environments drive the evolution of species.

    “It’s a significant advance in Earth science, and a major legacy of the international Ocean Drilling Program,” Zachos said.

    Coauthors Steven Bohaty, now at the University of Southampton, and Kate Littler, now at the University of Exeter, both worked with Zachos at UC Santa Cruz. The paper’s coauthors also include researchers at more than a dozen institutions around the world. This work was funded by the German Research Foundation (DFG), Natural Environmental Research Council (NERC), European Union’s Horizon 2020 program, National Science Foundation of China, Netherlands Earth System Science Centre, and the U.S. National Science Foundation.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    UCSC Lick Observatory, Mt Hamilton, in San Jose, California, Altitude 1,283 m (4,209 ft).

    UC Observatories Lick Autmated Planet Finder, fully robotic 2.4-meter optical telescope at Lick Observatory, situated on the summit of Mount Hamilton, east of San Jose, California, USA.

    The UCO Lick C. Donald Shane telescope is a 120-inch (3.0-meter) reflecting telescope located at the Lick Observatory, Mt Hamilton, in San Jose, California, Altitude 1,283 m (4,209 ft).

    UC Santa Cruz campus

    The University of California, Santa Cruz, opened in 1965 and grew, one college at a time, to its current (2008-09) enrollment of more than 16,000 students. Undergraduates pursue more than 60 majors supervised by divisional deans of humanities, physical & biological sciences, social sciences, and arts. Graduate students work toward graduate certificates, master’s degrees, or doctoral degrees in more than 30 academic fields under the supervision of the divisional and graduate deans. The dean of the Jack Baskin School of Engineering oversees the campus’s undergraduate and graduate engineering programs.

    UCSC is the home base for the Lick Observatory.

    Lick Observatory’s 36-inch Great Great Refractor telescope housed in the South (large) Dome of main building.

    Search for extraterrestrial intelligence expands at Lick Observatory
    New instrument scans the sky for pulses of infrared light
    March 23, 2015
    By Hilary Lebow
    1
    The NIROSETI instrument saw first light on the Nickel 1-meter Telescope at Lick Observatory on March 15, 2015. (Photo by Laurie Hatch) UCSC Lick Nickel telescope

    Astronomers are expanding the search for extraterrestrial intelligence into a new realm with detectors tuned to infrared light at UC’s Lick Observatory. A new instrument, called NIROSETI, will soon scour the sky for messages from other worlds.

    “Infrared light would be an excellent means of interstellar communication,” said Shelley Wright, an assistant professor of physics at UC San Diego who led the development of the new instrument while at the University of Toronto’s Dunlap Institute for Astronomy & Astrophysics.

    Wright worked on an earlier SETI project at Lick Observatory as a UC Santa Cruz undergraduate, when she built an optical instrument designed by UC Berkeley researchers. The infrared project takes advantage of new technology not available for that first optical search.

    Infrared light would be a good way for extraterrestrials to get our attention here on Earth, since pulses from a powerful infrared laser could outshine a star, if only for a billionth of a second. Interstellar gas and dust is almost transparent to near infrared, so these signals can be seen from great distances. It also takes less energy to send information using infrared signals than with visible light.

    Frank Drake, professor emeritus of astronomy and astrophysics at UC Santa Cruz and director emeritus of the SETI Institute, said there are several additional advantages to a search in the infrared realm.

    “The signals are so strong that we only need a small telescope to receive them. Smaller telescopes can offer more observational time, and that is good because we need to search many stars for a chance of success,” said Drake.

    The only downside is that extraterrestrials would need to be transmitting their signals in our direction, Drake said, though he sees this as a positive side to that limitation. “If we get a signal from someone who’s aiming for us, it could mean there’s altruism in the universe. I like that idea. If they want to be friendly, that’s who we will find.”

    Scientists have searched the skies for radio signals for more than 50 years and expanded their search into the optical realm more than a decade ago. The idea of searching in the infrared is not a new one, but instruments capable of capturing pulses of infrared light only recently became available.

    “We had to wait,” Wright said. “I spent eight years waiting and watching as new technology emerged.”

    Now that technology has caught up, the search will extend to stars thousands of light years away, rather than just hundreds. NIROSETI, or Near-Infrared Optical Search for Extraterrestrial Intelligence, could also uncover new information about the physical universe.

    “This is the first time Earthlings have looked at the universe at infrared wavelengths with nanosecond time scales,” said Dan Werthimer, UC Berkeley SETI Project Director. “The instrument could discover new astrophysical phenomena, or perhaps answer the question of whether we are alone.”

    NIROSETI will also gather more information than previous optical detectors by recording levels of light over time so that patterns can be analyzed for potential signs of other civilizations.

    “Searching for intelligent life in the universe is both thrilling and somewhat unorthodox,” said Claire Max, director of UC Observatories and professor of astronomy and astrophysics at UC Santa Cruz. “Lick Observatory has already been the site of several previous SETI searches, so this is a very exciting addition to the current research taking place.”

    NIROSETI will be fully operational by early summer and will scan the skies several times a week on the Nickel 1-meter telescope at Lick Observatory, located on Mt. Hamilton east of San Jose.

    The NIROSETI team also includes Geoffrey Marcy and Andrew Siemion from UC Berkeley; Patrick Dorval, a Dunlap undergraduate, and Elliot Meyer, a Dunlap graduate student; and Richard Treffers of Starman Systems. Funding for the project comes from the generous support of Bill and Susan Bloomfield.

     
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