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  • richardmitnick 9:42 am on July 13, 2019 Permalink | Reply
    Tags: "Carving the Seafloor", , Artist-at-Sea aboard R/V Falkor, David Bowen, Oceanography,   

    From Schmidt Ocean Institute: “Carving the Seafloor” 

    From Schmidt Ocean Institute

    7.12.19
    David Bowen

    1

    My name is David, and I am currently the Artist-at-Sea aboard R/V Falkor!

    The goal of my project as an Artist-at-Sea participant is to create CNC (computer numeric controlled) carvings of the seafloor that we pass over on our transit from Astoria to Honolulu. R/V Falkor is using a multi-beam sonar array to scan the seafloor during the entire transit. This system essentially sends out ultrasonic pulses to the ocean floor. These pulses bounce back to the ship within a certain time. The time it takes the pulses to get back is based on the distance that they travel. Thus, each pulse gives a specific depth, collected as a data point, based on how long it takes to get back to the ship. Latitude and Longitude information is assigned to each point giving a precise location of the depth. Thousands of these points assembled together create a point cloud. Following a few steps, from this point cloud, a three-dimensional model can be derived.

    2
    The computer software that takes the multibeam bathymetry data and changes it into readable steps for the CNC machine.

    I have set up a CNC machine aboard Falkor to produce carvings of these 3D models derived from the sonar data collected from the ocean floor during Falkor’s transit. The CNC machine uses stepper motors to precisely control a cutter along X (Latitude), Y (Longitude), and Z (Depth) coordinates. Using parallel passes, much like an inkjet printer, the CNC machine can carve very detailed surfaces.

    3
    The CNC machine

    The next steps are to convert the point cloud data gathered by the multi-beam sonar into a 3D model file type recognized by the software used to generate the toolpath for the CNC machine. A toolpath or G-code is essentially a series of steps for the machine to follow telling it where to make cuts as it carves into the surface of the material. The CNC machine will be carving pink extruded polystyrene. I chose this material because it is easy to carve, has a nice finish, and as an artificial material, it has a strong formal contrast to the natural seafloor that is being carved.

    The CNC machine has the potential to create a lot of dust while carving. Therefore, I have setup a durable and robust dust collection system for the machine.

    My hope for this project is to allow people to picture the ocean floor in a whole new way. When you can watch the seafloor being carved by the CNC, you can imagine the seafloor being formed hundreds of thousands of years ago.I look forward to see how the piece evolves while at sea.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Our Vision
    The world’s oceans understood through technological advancement, intelligent observation, and open sharing of information.

    Schmidt Ocean Institute RV Falkor

    Schmidt Ocean Institute ROV Subastian

    Schmidt Ocean Institute is a 501(c)(3) private non-profit operating foundation established in March 2009 to advance oceanographic research, discovery, and knowledge, and catalyze sharing of information about the oceans.

    Since the Earth’s oceans are a critically endangered and least understood part of the environment, the Institute dedicates its efforts to their comprehensive understanding across intentionally broad scope of research objectives.

    Eric and Wendy Schmidt established Schmidt Ocean Institute in 2009 as a seagoing research facility operator, to support oceanographic research and technology development focusing on accelerating the pace in ocean sciences with operational, technological, and informational innovations. The Institute is devoted to the inspirational vision of our Founders that the advancement of technology and open sharing of information will remain crucial to expanding the understanding of the world’s oceans.

     
  • richardmitnick 1:12 pm on July 11, 2019 Permalink | Reply
    Tags: , Coral on the move to escape sea heat, , , Oceanography,   

    From University of Washington and COSMOS: “Reefs on the move- Coral reefs shifting away from equator, new study finds” 

    U Washington

    From University of Washington

    AND

    Cosmos Magazine bloc

    From COSMOS Magazine

    July 9, 2019

    1
    Corals and kelp.Soyoka Muko/Nagasaki University

    Coral reefs are retreating from equatorial waters and establishing new reefs in more temperate regions, according to new research published July 4 in the journal Marine Ecology Progress Series. The researchers found that the number of young corals on tropical reefs has declined by 85% — and doubled on subtropical reefs — during the last four decades.

    “Climate change seems to be redistributing coral reefs, the same way it is shifting many other marine species,” said lead author Nichole Price, a senior research scientist at Bigelow Laboratory for Ocean Sciences in Maine. “The clarity in this trend is stunning, but we don’t yet know whether the new reefs can support the incredible diversity of tropical systems.”

    As climate change warms the ocean, subtropical environments are becoming more favorable for corals than the equatorial waters where they traditionally thrived. This is allowing drifting coral larvae to settle and grow in new regions. These subtropical reefs could provide refuge for other species challenged by climate change and new opportunities to protect these fledgling ecosystems.

    “This study is a great example of the importance of collaborating internationally to assess global trends associated with climate change and project future ecological interactions,” said co-author Jacqueline Padilla-Gamiño, an assistant professor at the University of Washington School of Aquatic and Fishery Sciences. “It also provides a nugget of hope for the resilience and survival of coral reefs.”

    The researchers believe that only certain types of coral are able to reach these new locations, based on how far the microscopic larvae can swim and drift on currents before they run out of their limited fat stores. The exact composition of most new reefs is currently unknown, due to the expense of collecting genetic and species diversity data.

    “We are seeing ecosystems transition to new blends of species that have never coexisted, and it’s not yet clear how long it takes for these systems to reach equilibrium,” said co-author Satoshi Mitarai, an associate professor at Okinawa Institute of Science and Technology Graduate University who earned his doctorate at the UW. “The lines are really starting to blur about what a native species is, and when ecosystems are functioning or falling apart.”

    2
    The study site on Palmyra Atoll, one of the Northern Line Islands that lies between Hawaii and American Samoa.
    Nichole Price/Bigelow Laboratory for Ocean Sciences

    This experiment in the Palmyra Atoll National Wildlife Refuge in the Pacific is allowing researchers to enumerate the number of baby corals settling on a reef.

    Recent studies show that corals are establishing new reefs in temperate regions as they retreat from increasingly warmer waters at the equator.

    Writing in the journal Marine Ecology Progress Series [above], researchers from 17 institutions in six countries report that the number of young corals has declined by 85% on tropical reefs during the last four decades, but -doubled on subtropical reefs.

    “Climate change seems to be redistributing coral reefs, the same way it is shifting many other marine species,” says lead author Nichole Price, from Bigelow Laboratory for Ocean Sciences, US.

    “The clarity in this trend is stunning, but we don’t yet know whether the new reefs can support the incredible diversity of tropical systems.”

    The research team has compiled a global database of studies dating back to 1974, when record-keeping began. They hope other scientists will add to it, making it increasingly comprehensive and useful to other research questions.

    See the full U Washington article here .
    See the full COSMOS article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    u-washington-campus
    The University of Washington is one of the world’s preeminent public universities. Our impact on individuals, on our region, and on the world is profound — whether we are launching young people into a boundless future or confronting the grand challenges of our time through undaunted research and scholarship. Ranked number 10 in the world in Shanghai Jiao Tong University rankings and educating more than 54,000 students annually, our students and faculty work together to turn ideas into impact and in the process transform lives and our world. For more about our impact on the world, every day.
    So what defines us —the students, faculty and community members at the University of Washington? Above all, it’s our belief in possibility and our unshakable optimism. It’s a connection to others, both near and far. It’s a hunger that pushes us to tackle challenges and pursue progress. It’s the conviction that together we can create a world of good. Join us on the journey.

     
  • richardmitnick 11:16 am on July 9, 2019 Permalink | Reply
    Tags: , Large hole in the sea ice — known as a polynya, Oceanography,   

    From University of Washington: “Mysterious holes in Antarctic sea ice explained by years of robotic data” 

    U Washington

    From University of Washington

    June 10, 2019
    Hannah Hickey

    1
    The hole in the sea ice offshore of the Antarctic coast as seen by a NASA satellite on Sept. 25, 2017. NASA Worldview/NASA Blue Marble

    The winter ice on the surface of Antarctica’s Weddell Sea occasionally forms an enormous hole. A hole that appeared in 2016 and 2017 drew intense curiosity from scientists and reporters. Though even bigger gaps had formed decades before, this was the first time oceanographers had a chance to truly monitor the unexpected gap in Antarctic winter sea ice.

    A new study led by the University of Washington combines satellite images of the sea ice cover, robotic drifters and even seals outfitted with sensors to better understand the phenomenon. The research explores why this hole appears in only some years, and what role it could play in the larger ocean circulation.

    The study was published June 10 in the journal Nature.

    “We thought this large hole in the sea ice — known as a polynya — was something that was rare, maybe a process that had gone extinct. But the events in 2016 and 2017 forced us to reevaluate that,” said lead author Ethan Campbell, a UW doctoral student in oceanography. “Observations show that the recent polynyas opened from a combination of factors — one being the unusual ocean conditions, and the other being a series of very intense storms that swirled over the Weddell Sea with almost hurricane-force winds.”

    A “polynya,” a Russian word that roughly means “hole in the ice,” can form near shore as wind pushes the ice around. But it can also appear far from the coast and stick around for weeks to months, where it acts as an oasis for penguins, whales and seals to pop up and breathe.

    2
    Satellite images from Aug. 30, 2017 through Dec. 2, 2017 show the rarely-seen opening in the late Southern Hemisphere winter sea ice. The two plus signs show the location of oceanographic robots that were trapped in a spinning column of water above an underwater mountain known as Maud Rise.AMSR2-ASI/University of Bremen

    This particular spot far from the Antarctic coast often has small openings and has seen large polynyas before. The biggest known polynyas at that location were in 1974, 1975 and 1976, just after the first satellites were launched, when an area the size of New Zealand remained ice-free through three consecutive Antarctic winters despite air temperatures far below freezing.

    Campbell joined the UW as a graduate student in 2016 to better understand this mysterious phenomenon. In a stroke of scientific luck, a big one appeared for the first time in decades. A NASA satellite image in August 2016 drew public attention to a 33,000-square-kilometer (13,000-square-mile) gap that appeared for three weeks. An even bigger gap, of 50,000 square kilometers (19,000 square miles) appeared in September and October of 2017.

    The Southern Ocean is thought to play a key role in global ocean currents and carbon cycles, but its behavior is poorly understood. It hosts some of the fiercest storms on the planet, with winds whipping uninterrupted around the continent in the 24-hour darkness of polar winter. The new study used observations from the Southern Ocean Carbon and Climate Observations and Modeling project, or SOCCOM, which puts out instruments that drift with the currents to monitor Antarctic conditions.

    The study also used data from the long-running Argo ocean observing program, elephant seals that beam data back to shore, weather stations and decades of satellite images.

    3
    Ocean measurements were also collected by seals swimming under the sea ice with temporary satellite tags, showing normal water conditions in the years that did not have large polynyas.Dan Costa/University of California, Santa Cruz

    “This study shows that this polynya is actually caused by a number of factors that all have to line up for it to happen,” said co-author Stephen Riser, a UW professor of oceanography. “In any given year you could have several of these things happen, but unless you get them all, then you don’t get a polynya.”

    The study shows that when winds surrounding Antarctica draw closer to shore, they promote stronger upward mixing in the eastern Weddell Sea. In that region, an underwater mountain known as Maud Rise forces dense seawater around it and leaves a spinning vortex above. Two SOCCOM instruments were trapped in the vortex above Maud Rise and recorded years of observations there.

    Analysis shows that when the surface ocean is especially salty, as seen throughout 2016, strong winter storms can set off an overturning circulation. Warmer, saltier water from the depths gets churned up to the surface, where air chills it and makes it denser than the water below. As that water sinks, relatively warmer deep water of about 1 degree Celsius (34 F) replaces it, creating a feedback loop where ice can’t reform.

    Under climate change, fresh water from melting glaciers and other sources will make the Southern Ocean’s surface layer less dense, which might mean fewer polynyas in the future. But the new study questions that assumption. Many models show that the winds circling Antarctica will become stronger and draw closer to the coast — the new paper suggests this would encourage more polynyas to form, not fewer.

    4
    Ethan Campbell (right) and Stephen Riser (second from left) view one of the SOCCOM monitoring instruments built at the UW and then released in the Southern Ocean, with UW alumnus Chanelle Cadot (far left), now at NOAA, and UW graduate student Rosalind Echols (second from left).Dennis Wise/University of Washington

    These are the first observations to prove that even a smaller polynya like the one in 2016 moves water from the surface all the way to the deep ocean.

    “Essentially it’s a flipping over of the entire ocean, rather than an injection of surface water on a one-way trip from the surface to the deep,” said co-author Earle Wilson, who recently completed his doctorate in oceanography at the UW.

    One way that a surface polynya matters for the climate is for the deepest water in the oceans, known as Antarctic Bottom Water. This cold, dense water lurks below all the other water. Where and how it’s created affects its characteristics, and would have ripple effects on other major ocean currents.

    “Right now people think most of the bottom water is forming on the Antarctic shelf, but these big offshore polynyas might have been more common in the past,” Riser said. “We need to improve our models so we can study this process, which could have larger-scale climate implications.”

    Large and long-lasting polynyas can also affect the atmosphere, because deep water contains carbon from lifeforms that have sunk over centuries and dissolved on their way down. Once this water reaches the surface that carbon could be released.

    “This deep reservoir of carbon has been locked away for hundreds of years, and in a polynya it might get ventilated at the surface through this really violent mixing,” Campbell said. “A large carbon outgassing event could really whack the climate system if it happened multiple years in a row.”

    Other co-authors on the paper are Kent Moore at the University of Toronto, who was the 2016-17 Canada Fulbright Visiting Chair in Arctic Studies at the UW; Casey Brayton at the University of South Carolina; and Lynne Talley and Matthew Mazloff from Scripps Institution of Oceanography at the University of California, San Diego. SOCCOM is funded by the National Science Foundation. Campbell was supported by the U.S. Department of Defense through the National Defense Science & Engineering Graduate Fellowship program. Additional funding is from the NSF, the National Oceanic and Atmospheric Administration, the University of Washington and Scripps Institution of Oceanography.

    ###

    For more information, contact Campbell at ethancc@uw.edu and 224-388-0301, Riser at riser@uw.edu and 206-543-1187 or Wilson at earlew@uw.edu.

    NSF: PLR-1425989; NOAA: NA15OAR4320063

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    u-washington-campus
    The University of Washington is one of the world’s preeminent public universities. Our impact on individuals, on our region, and on the world is profound — whether we are launching young people into a boundless future or confronting the grand challenges of our time through undaunted research and scholarship. Ranked number 10 in the world in Shanghai Jiao Tong University rankings and educating more than 54,000 students annually, our students and faculty work together to turn ideas into impact and in the process transform lives and our world. For more about our impact on the world, every day.
    So what defines us —the students, faculty and community members at the University of Washington? Above all, it’s our belief in possibility and our unshakable optimism. It’s a connection to others, both near and far. It’s a hunger that pushes us to tackle challenges and pursue progress. It’s the conviction that together we can create a world of good. Join us on the journey.

     
  • richardmitnick 2:54 pm on July 8, 2019 Permalink | Reply
    Tags: "How to Protect Corals Facing Climate Change", , , Oceanography,   

    From Rutgers University: “How to Protect Corals Facing Climate Change” 

    Rutgers smaller
    Our Great Seal.

    From Rutgers University

    July 8, 2019

    Todd Bates
    848-932-0550
    todd.bates@rutgers.edu

    Conserving a wide range of coral habitats is the best strategy.

    The best way to protect corals threatened by climate change is to conserve a wide range of their habitats, according to a study in Nature Climate Change. The finding likely applies to conservation efforts for many other species in the ocean and on land, including trees and birds.

    1
    A coral reef off Cuatros Islas in the Philippines.
    Photo: Michelle Stuart/Rutgers University-New Brunswick

    “Rather than conserving just the cold places with corals, we found that the best strategies will conserve a wide diversity of sites,” said co-author Malin Pinsky, an associate professor in the Department of Ecology, Evolution, and Natural Resources at Rutgers University–New Brunswick. “Hot reefs are important sources of heat-tolerant corals, while cold sites and those in between are important future refuges and stepping stones for corals as the water heats up.”

    Worldwide, about 500 million people rely on coral reefs for food and livelihoods, with billions of dollars a year boosting economies, according to the National Oceanic and Atmospheric Administration. Reefs protect coastlines from storms and erosion; provide habitat as well as spawning and nursery grounds for fish; and result in income from fishing, recreation and tourism, among other benefits.

    But corals face several threats, including global warming, warm water bleaching episodes, reef destruction, nutrient pollution and ocean acidification from carbon dioxide emitted when fossils fuels burn.

    Predictions about the future of corals are generally grim, the study notes, but there is growing recognition that they can adapt rapidly to a changing climate.

    Pinsky and scientists at the University of Washington, Utah State University, Coral Reef Alliance, Stanford University and University of Queensland in Australia modeled how different conservation strategies might help coral reefs survive climate change. Previous research addressed where to establish marine protected areas to help corals, but nearly all studies overlooked the fact that corals can also evolve in response to climate change, Pinsky said.

    The researchers evaluated a range of potential conservation strategies, including those that: protected sites where existing coral populations appeared to be “preadapted” to future conditions; conserved sites suitable for corals to move to in the future; conserved sites with large populations of certain species; conserved the smallest populations; or protected reef sites chosen at random. The researchers found that conserving many different kinds of reefs would work best.

    “Corals are facing a gauntlet over the coming years and decades from warming oceans, but we found that reef conservation in general can really boost corals’ ability to evolve and cope with these changes,” Pinsky said. “There is strength in diversity, even when it comes to corals. We need to think not only about saving the cooler places, where corals can best survive in the future, but also the hot places that already have heat-resistant corals. It’s about protecting a diversity of habitats, which scientists hadn’t fully appreciated before.”

    The researchers are developing regional models to test conservation strategies for the Caribbean Sea, the central Pacific Ocean and the Coral Triangle in the western Pacific, he said. They want to understand how the most effective conservation strategies differ from one region to the next.

    “We are working closely with conservation groups that will be applying the guidelines and findings from this study to coral reef conservation around the world,” Pinsky said.

    See the full article here .


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    rutgers-campus

    Rutgers, The State University of New Jersey, is a leading national research university and the state’s preeminent, comprehensive public institution of higher education. Rutgers is dedicated to teaching that meets the highest standards of excellence; to conducting research that breaks new ground; and to providing services, solutions, and clinical care that help individuals and the local, national, and global communities where they live.

    Founded in 1766, Rutgers teaches across the full educational spectrum: preschool to precollege; undergraduate to graduate; postdoctoral fellowships to residencies; and continuing education for professional and personal advancement.

    As a ’67 graduate of University college, second in my class, I am proud to be a member of

    Alpha Sigma Lamda, National Honor Society of non-tradional students.

     
  • richardmitnick 5:25 pm on July 6, 2019 Permalink | Reply
    Tags: , , Oceanography,   

    From Schmidt Ocean Institute: “Bringing the Bubbles Home” 

    From Schmidt Ocean Institute

    Observing Seafloor Methane Seeps at the Edge of Hydrate Stability

    7.6.19
    Amanda Demopoulos

    7
    USGS scientist Amanda Demopoulos, lead scientist for this expedition, sits at the bow of the R/V Falkor. Shelton Du Preez / Schmidt Ocean Institute

    As the R/V Falkor passes Cape Disappointment back into the mouth of the Columbia River, with Astoria rising in the background, I reflect back on our 21 days at sea. And what comes back to me the most is I never knew there was so much that can be studied about bubbles.

    2
    R/V Falkor

    2
    USGS scientist Amanda Demopoulos, lead scientist for this expedition, unloads several push cores taken from the sediment at the ocean floor by ROV SuBastian. Shelton Du Preez / Schmidt Ocean Institute

    “I have studied animals at seeps on most of the United States continental margins and looked at meiofauna to the megafauna. It had never occurred to me that there were scientists out there doing the same for bubbles. But thanks to the work of USGS, Schmidt Ocean Institute, and our partners at the British Geological Survey, GEOMAR, and the University of North Carolina-Chapel Hill, I’m getting to see just how much can be done with these bubbles.”

    Seep Science to Scale

    We have really done something impressive here with these seeps. It is pretty rare that a group of scientists can combine so many disciplines to study this specific type of environment in so many ways.

    3
    Just a sampling of the scientists and equipment of this expedition into methane seeps on the Cascadia Margin
    From Left to Right: USGS biologist Jennie McClain-Counts, USGS benthic ecologist Amanda Demopoulos, British Geological Survey geologist Diana Sahy, OSU/NOAA marine geochemist Tamara Baumberger, CCU graduate student Charlotte Kollman, USGS/NAGT intern Penny McCowen, and USGS research oceanographer Nancy Prouty. Shelton Du Preez / Schmidt Ocean Institute

    We have Bill and the Falkor mapping all of these bubble plumes from the seeps. Diana and Nancy are looking at what made the seeps and how the seeps then make the rocks that surround them. Jens and Tim are quantifying how much methane is coming out and where it is going. Tamara is looking at the methane itself, what is in it and how it formed. Howard and Adam are looking at what is eating the methane and how fast they are doing it. And Jennie and I are looking at what depends on the seeps for habitat and food, either directly or indirectly.

    4
    A multibeam map of Astoria Canyon 500, created by USGS scientist Bill Danforth from data collected by R/V Falkor.
    Bill Danforth / USGS

    “And the best part of this is that we are creating this incredible dataset that will be able to be scaled from an individual seep to entire regions. We will be able to use our work to predict habitats based on profiles of plumes and associated seafloor characteristics and then apply that all across the U.S. Pacific margin, and maybe even in the Atlantic too.”

    Personal Focus

    “This has been a truly rewarding experience for me. I have never had the opportunity to focus on a habitat system so intricately. Our Astoria Canyon 500 site is the perfect example. We’ve mapped the heck out of it; I do not think there is a square inch that Bill and the Falkor have not scanned and rescanned with the multibeam sonar.”

    5
    USGS scientist Amanda Demopoulos, lead scientist on this cruise, helps unload the collections from a Grays Canyon dive by ROV SuBastian. Shelton Du Preez / Schmidt Ocean Institute

    “Plus we have been able to spend 12 hours here, then revisit the site to see what has changed a few days later and investigate how the seeps behave at different times of day, thanks to the Gas Quant, Bubble Box and UNC Landers.

    Last but not least, we have been able to observe the animals that live here too, throughout the day and across multiple days, to see who is here, where they are living, and what they are eating.”

    Next Steps

    So what’s next? Well, quite a lot of lab work, that is for sure. Thanks to Falkor’s facilities and wonderful ROV team, we have been able to collect a tremendous array of samples, from gas to clams to rocks. Now we will be taking that back to our various labs and analyzing the samples to answer critical questions.

    For example—What created the system that fuels these seeps? How does the methane migrate through the sediments to be emitted at the ocean floor in the first place? Nancy and Diana’s work will tell us the history of these rocks and sediments. If Tamara finds more helium, that might indicate that some of these seeps include gas from deep in the zone where two tectonic plates interact on this margin.

    Another question is whether chemical and biological processes work differently at the seafloor than when the samples are in the lab? Howard and Adam’s experiment at the seafloor is the first time we have been able to measure the rate of a bacterial process important for methane dynamics at the actual pressure, temperature, and environmental conditions at which they actually occur.

    6
    Howard Mendlovitz, Research Engineer in the Department of Marine Sciences at the University of North Carolina and Amanda Demopoulos, Research Benthic Ecologist for the U.S. Geological Survey (USGS) collecting clam samples from the dive at Heceta, one of the areas of focus for seepage. Shelton Du Preez / Schmidt Ocean Institute

    Finally, how are seeps connected to the broader ocean ecosystems? We have seen in the Atlantic and Gulf of Mexico that seeps create extensive ecosystems, composed of a diversity of habitat types, including bacterial mats, tubeworms, clams, and authigenic carbonate, and by expanding on previous research in the region, we have confirmed that in a big way here in the Pacific. However, the degree to which these benthic habitats interact with the water column in terms of transferring carbon, or energy, to mid-water organisms, such as pelagic fishes and invertebrates, is unclear.

    For instance, do creatures living in the mid-water column descend to feed on the communities around the seeps, then swim up to the feed on the surface communities? If so, then that means the nutrients created at these deep seeps may well end up playing an important role near the surface too. This would have significant implications for overall ocean health.

    Going Forward

    It is important to remember that not that long ago the seafloor was thought to be an empty abyssal plain, devoid of life and features. If you have followed along during SuBastian’s livecasts, you have seen how wrong that perspective is. The more we map and study the seafloor, the more we find out just how full of life and activity it is.

    In fact, in just the last five years, we have discovered hundreds of these methane seeps on the U.S. Atlantic, Pacific, and Gulf of Mexico margins. How important are these seeps in the overall biological activity of the ocean? How do the seeps tie into the geologic forces that move our planet? These are the questions that we have sought to address on this cruise with Schmidt Ocean Institute and on past cruises with other partners.

    I hope you have enjoyed following along as we have discovered new seeps, rediscovered old seeps, and gathered staggering amounts of new data. We have years of work ahead of us, but thanks to the support of Schmidt Ocean Institute and all of our collaborators here, we have had a great start. Thank you to the wonderful crew of the R/V Falkor and ROV SuBastian, and thank you to Schmidt Ocean Institute for enabling this incredible research opportunity.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Our Vision
    The world’s oceans understood through technological advancement, intelligent observation, and open sharing of information.

    Schmidt Ocean Institute RV Falkor

    Schmidt Ocean Institute ROV Subastian

    Schmidt Ocean Institute is a 501(c)(3) private non-profit operating foundation established in March 2009 to advance oceanographic research, discovery, and knowledge, and catalyze sharing of information about the oceans.

    Since the Earth’s oceans are a critically endangered and least understood part of the environment, the Institute dedicates its efforts to their comprehensive understanding across intentionally broad scope of research objectives.

    Eric and Wendy Schmidt established Schmidt Ocean Institute in 2009 as a seagoing research facility operator, to support oceanographic research and technology development focusing on accelerating the pace in ocean sciences with operational, technological, and informational innovations. The Institute is devoted to the inspirational vision of our Founders that the advancement of technology and open sharing of information will remain crucial to expanding the understanding of the world’s oceans.

     
  • richardmitnick 11:46 am on July 6, 2019 Permalink | Reply
    Tags: , , It is made up of some 20 million metric tons of Sargassum algae– more than the weight of 200 fully loaded aircraft carriers., Oceanography, Sargassum provides habitats for turtles crabs fish and birds while also producing oxygen for marine life to live off through the process of photosynthesis., , Scientists have measured what they say is the largest seaweed bloom on record stretching 8850 kilometres (nearly 5500 miles) across the Atlantic Ocean, Too much of the algae can cause problems in terms of restricting the movement and breathing of certain marine species.   

    From Science Alert: “Scientists Discover The Largest Seaweed Bloom Ever Found, And It’s Still Growing” 

    ScienceAlert

    From Science Alert

    6 JUL 2019
    DAVID NIELD

    Scientists have measured what they say is the largest seaweed bloom on record, stretching 8,850 kilometres (nearly 5,500 miles) across the Atlantic Ocean and made up of some 20 million metric tons of Sargassum algae – more than the weight of 200 fully loaded aircraft carriers.

    The Great Atlantic Sargassum Belt, as it’s being called, is expanding due to nutrients washed out from the Amazon river on one side and the West African coast on the other, some of which may be due to increased deforestation and fertiliser use.

    Using satellite data from NASA as well as samples collected in the field, the researchers have identified a tipping point that happened back in 2011. Since then, there have been major blooms almost every year, and there’s no sign of that trend changing – the latest spread stretched all the way from West Africa to the Gulf of Mexico.

    2
    Spreading sargassum. (Wang et al., Science., 2019)

    The scientists have linked that change to an increase in deforestation and fertiliser use in Brazil and across the Amazon, beginning at the start of the decade, though the association isn’t yet clear-cut.

    While the researchers aren’t ready to say exactly what’s causing the bloom, they feel confident it’s not going away any time soon.

    “The evidence for nutrient enrichment is preliminary and based on limited field data and other environmental data, and we need more research to confirm this hypothesis,” says study leader and oceanographer Chuanmin Hu, from the University of South Florida.

    “On the other hand, based on the last 20 years of data, I can say that the belt is very likely to be a new normal.”

    So what does this mammoth bloom mean for our oceans? Unfortunately we don’t know enough to say just yet.

    Seaweed blooms like this aren’t necessarily bad for the ocean: sargassum provides habitats for turtles, crabs, fish and birds, while also producing oxygen for marine life to live off through the process of photosynthesis.

    But too much of the algae can cause problems, in terms of restricting the movement and breathing of certain marine species, especially around coastal regions. After it dies, the sargassum can choke corals and seagrass if there’s too much of it in the water.

    Rotting sargassum on the beach also gives off a rotten egg smell thanks to the hydrogen sulphide it releases, and that means an unpleasant experience for locals and tourists, as well as potential impacts on health (for those with asthma, for example).

    3
    (Brian Cousin/Florida Atlantic University’s Harbor Branch Oceanographic Institute)

    The size of the blooms now peak between April and July before slowly dissipating, but some seeds that get left over in the winter then go on to contribute to larger swathes of sargassum the next summer.

    “The ocean’s chemistry must have changed in order for the blooms to get so out of hand,” says Hu. “They are probably here to stay.”

    Many factors play into sargassum growth, including the salinity and temperature of the water, and as yet the scientists don’t have direct readings for nutrient levels for all the years covered by the study – in some cases it’s been estimated based on other signals.

    In 2011 the bloom was particularly widespread, and we’re still seeing the momentum for that now. As well as more nutrients being discharged from the Amazon river, the researchers say, an upwelling or rising in the sea level off West Africa also contributed more nutrients (lifted up from deeper water to the surface).

    Ultimately that led to the enormous bloom that was recorded last summer and detailed in this new study. Now they know the extent of it, the researchers want to further investigate its causes and possible consequences – on precipitation, ocean currents, human activity and more.

    “We hope this provides a framework for improved understanding and response to this emerging phenomenon,” says Hu. “We need a lot more follow-on work.”

    The research has been published in Science.

    See the full article here .


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  • richardmitnick 10:06 am on June 27, 2019 Permalink | Reply
    Tags: A collaborative research team has explored the largest known coral reef in the mesophotic zone located in the Hawaiian Archipelago., Close to half of all corals in the ocean have died in the past 30 years, Hotspots for biodiversity, Mesophotic reefs in Hawaii are stunning in their sheer size and abundance, Mesophotic zone-about 100 to at least 500 feet below the surface — little to no light breaks through, Oceanography, The team was from University of Washington College of Charleston University of California Berkeley University of Hawaii and other institutions   

    From University of Washington: “Deep submersible dives shed light on rarely explored coral reefs” 

    U Washington

    From University of Washington

    June 19, 2019
    Michelle Ma

    Just beyond where conventional scuba divers can go is an area of the ocean that still is largely unexplored. In waters this deep — about 100 to at least 500 feet below the surface — little to no light breaks through.

    1
    A submersible on the surface of the water off the coast of Maui, Hawaii.Jacqueline Padilla-Gamiño/University of Washington

    Researchers must rely on submersible watercraft or sophisticated diving equipment to be able to study ocean life at these depths, known as the mesophotic zone. These deep areas span the world’s oceans and are home to extensive coral reef communities, though little is known about them because it is so hard to get there.

    A collaborative research team from the University of Washington, College of Charleston, University of California Berkeley, University of Hawaii and other institutions has explored the largest known coral reef in the mesophotic zone, located in the Hawaiian Archipelago, through a series of submersible dives. There, they documented life along the coral reef, finding a surprising amount of coral living in areas where light levels are less than 1% of the light available at the surface.

    Their findings were published this spring in the journal Limnology and Oceanography.

    2
    Corals that live in the mesophotic zone need very little light to survive. Hawaii Undersea Research Laboratory

    “Because mesophotic corals live close to the limits of what is possible, understanding their physiology will give us clues of the extraordinary strategies corals use to adapt to low-light environments,” said lead author Jacqueline Padilla-Gamiño, an assistant professor in the UW School of Aquatic and Fishery Sciences.

    Knowing how these deep coral reefs function is important because they appear to be hotspots for biodiversity, and home to many species found only in those locations, Padilla-Gamiño explained. Additionally, close to half of all corals in the ocean have died in the past 30 years, mostly due to warm water temperatures that stress their bodies, causing them to bleach and eventually die. This has been documented mostly in shallower reefs where more research has occurred. Scientists say that more information about deeper reefs in the mesophotic zone is critical for preserving that habitat.

    “Mesophotic reefs in Hawaii are stunning in their sheer size and abundance,” said co-author Heather Spalding at College of Charleston. “Although mesophotic environments are not easily seen, they are still potentially impacted by underwater development, such as cabling and anchoring, and need to be protected for future generations. We are on the tip of the iceberg in terms of understanding what makes these astounding reefs tick.”

    3
    A researcher prepares to lower the submersible on a dive off the coast of Maui, Hawaii.Hawaii Undersea Research Laboratory

    Padilla-Gamiño was on board during two of the team’s eight submersible dives off the coast of Maui that took place from 2010 to 2011. Each dive was a harrowing adventure: Researchers spent up to eight hours in cramped quarters in the submersible that was tossed from the back of a larger boat, then disconnected once the submersible reached the water.

    Once in the mesophotic zone, they collected specimens using a robot arm, and captured video footage and photos of life that has rarely been seen by humans.

    “It’s a really unbelievable place,” Padilla-Gamiño said. “What is surprising is that, in theory, these corals should not be there because there’s so little light. Now we’re finally understanding how they function to be able to live there.”

    4
    A robot arm attached to the submersible collects coral from the mesophotic zone off the coast of Maui.Hawaii Undersea Research Laboratory

    By collecting coral samples and analyzing their physiology, the researchers found that different corals in the mesophotic zone use different strategies to deal with low amounts of light. For example, some species of corals change the amount of pigments at deeper depths, while other species change the type and size of symbionts, which are microscopic seaweeds living inside the tissue of corals, Padilla-Gamiño explained. These changes allow corals to acquire and maximize the light available to perform photosynthesis and obtain energy.

    Additionally, the corals at deeper depths are likely eating other organisms like zooplankton to increase their energy intake and survive under very low light levels. They probably do this by filter feeding, Padilla-Gamiño said, but more research is needed to know for sure.

    The researchers hope to collect more live coral samples from the mesophotic zone to be able to study in the lab how the symbionts, and the corals they live inside, function.

    4
    Researchers motor back to the town of Lahaina, West Maui, near their dive site.Ray Boland

    “The more we can study this, the more information we can have about how life works. This is a remarkable system with enormous potential for discovery,” Padilla-Gamiño said. “Our studies provide the foundation to explore physiological flexibility, identify novel mechanisms to acquire light and challenge current paradigms on the limitations of photosynthetic organisms like corals living in deeper water.”

    Other co-authors are Celia Smith at University of Hawaii at Mānoa; Melissa Roth at UC Berkeley; Lisa Rodrigues at Villanova University; Christina Bradley at Salisbury University; and Robert Bidigare and Ruth Gates at Hawaii Institute of Marine Biology.

    The study was funded by the National Oceanic and Atmospheric Administration and the National Science Foundation.

    See the full article here .


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    Please help promote STEM in your local schools.

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    u-washington-campus
    The University of Washington is one of the world’s preeminent public universities. Our impact on individuals, on our region, and on the world is profound — whether we are launching young people into a boundless future or confronting the grand challenges of our time through undaunted research and scholarship. Ranked number 10 in the world in Shanghai Jiao Tong University rankings and educating more than 54,000 students annually, our students and faculty work together to turn ideas into impact and in the process transform lives and our world. For more about our impact on the world, every day.
    So what defines us —the students, faculty and community members at the University of Washington? Above all, it’s our belief in possibility and our unshakable optimism. It’s a connection to others, both near and far. It’s a hunger that pushes us to tackle challenges and pursue progress. It’s the conviction that together we can create a world of good. Join us on the journey.

     
  • richardmitnick 11:34 am on June 24, 2019 Permalink | Reply
    Tags: "As countries battle for control of North Pole, , , Oceanography, science is the ultimate winner",   

    From Science Magazine: “As countries battle for control of North Pole, science is the ultimate winner” 

    AAAS
    From Science Magazine

    Jun. 20, 2019
    Richard Kemeny

    1
    Canadian and U.S. Coast Guard ships worked together to map the Arctic sea floor for continental shelf claims. DVIDSHUB/FLICKR/CC BY 2.0

    A competition for the North Pole heated up last month, as Canada became the third country to claim—based on extensive scientific data—that it should have sovereignty over a large swath of the Arctic Ocean, including the pole. Canada’s bid, submitted to the United Nations’s Commission on the Limits of the Continental Shelf (CLCS) on 23 May, joins competing claims from Russia and Denmark. Like theirs, it is motivated by the prospect of mineral riches: the large oil reserves believed to lie under the Arctic Ocean, which will become more accessible as the polar ice retreats. And all three claims, along with dozens of similar claims in other oceans, rest on extensive seafloor mapping, which has proved to be a boon to science, whatever the outcome for individual countries. The race to obtain control over parts of the sea floor has “dramatically changed our understanding of the oceans,” says marine geophysicist Larry Mayer of the University of New Hampshire in Durham.

    Coastal nations have sovereign rights over an exclusive economic zone (EEZ), extending by definition 200 nautical miles (370 kilometers) out from their coastline. But the 1982 United Nations Convention on the Law of the Sea opened up the possibility of expanding that zone if a country can convince CLCS that its continental shelf extends beyond the EEZ’s limits.

    Most of the 84 submissions so far were driven by the prospect of oil and gas, although advances in deep-sea mining technology have added new reasons to apply. Brazil, for example, filed an application in December 2018 that included the Rio Grande Rise, a deep-ocean mountain range 1500 kilometers southeast of Rio De Janeiro that’s covered in cobalt-rich ferromanganese crusts.

    To make a claim, a country has to submit detailed data on the shape of the sea floor and on its sediment, which is thicker on the shelf than in the deep ocean. The data come from sonar, which reveals seafloor topography, and seismic profiling, which uses low-frequency booms to probe the sediment. Canada’s bid also enlisted ships to conduct high-resolution gravimetry—measurements of gravity anomalies that reveal seafloor structure. Elevated gravity readings are found over higher-density mantle rocks found in oceanic crust, and lower readings over lighter, continental structures. And the bid used analyses of 800 kilograms of rock samples dredged up from the sea floor, whose composition can distinguish continental from ocean crust.

    The studies don’t come cheap; Canada’s 17 Arctic expeditions alone cost more than CA$117 million. But the work by the three countries vying for the Arctic—and that of dozens of others elsewhere in the world—has been a bonanza for oceanography. In the Arctic alone, the mapping has revealed several sunken mountains, previously missed or undetected by older sonar methods. Hundreds of pockmarks found on the Chukchi Cap, a submarine plateau extending out from Alaska, suggest that bursts of previously frozen methane have erupted from the seabed, a phenomenon that could accelerate climate change. And gaps discovered across submarine ridges allow currents to flow from basin to basin, with “important ramifications on the distribution of heat in the Arctic and on overall modeling of climate and ice melting,” Mayer says.

    2
    Who owns the North Pole? Countries can clain the sea floor beyond the 200-nautical-mile (370-kilometer) ex-clusive economic zone (EEZ) if data show it to be an extension of the continental shelf (below). Russia Denmark and Canada have submitted overlapping claims in the Artic Ocean.

    CLCS, composed of 21 scientists in fields such as geology and hydrography who are elected by member states, has accepted 24 of the 28 claims it has finished evaluating, some partially or with caveats; in several cases, it has asked for follow-up submissions with more data. Australia was the first country to succeed, adding 2.5 million square kilometers to its territory in 2008. New Zealand gained undersea territory six times larger than its terrestrial area. But CLCS only judges the merit of each individual scientific claim; it has no authority to decide boundaries when claims overlap. To do that, countries have to turn to diplomatic channels once the science is settled.

    The three claims on the North Pole revolve around the Lomonosov Ridge, an underwater mountain system that runs from Ellesmere Island in Canada’s Qikiqtaaluk region to the New Siberian Islands of Russia, passing the North Pole. Both countries claim the ridge is geologically connected to their continent, whereas Denmark says it is also tied to Greenland, a Danish territory. As the ridge is thought to be continental crust, the territorial extensions could be extensive. (U.S. scientists should finish mapping in the Arctic in about 2 years, says Mayer, who is involved in that effort, but as one of the few countries that hasn’t ratified the Law of the Sea convention, the United States can’t file an official submission.)

    Tensions flared when Russia planted a titanium flag on the sea floor beneath the North Pole in 2007, after CLCS rejected its first claim, saying more data were needed. The Canadian foreign minister at the time likened the move to the land grabs of early European colonizers. Not that the North Pole has any material value: “The oil potential there is zip,” says geologist Henry Dick of the Woods Hole Oceanographic Institution in Massachusetts. “The real fight is over the Amerasian Basin,” Dick says (see map, above) where large amounts of oil are thought to be locked up.

    It will take years, perhaps decades, for CLCS to rule on the overlapping Arctic claims. Whoever wins the scientific contest still faces a diplomatic struggle.

    Denmark, Russia, and Canada have expressed their desire to settle the situation peacefully. “Russia actually has played nice on this and stopped at the North Pole,” rather than extending its claim along the length of the ridge, says Philip Steinberg, a political geographer at Durham University in the United Kingdom. Denmark had no such qualms and put in a claim up to the edge of Russia’s EEZ, “even though there’s no way in hell they’ll get that,” when it comes to the diplomatic discussions, Steinberg says.

    One solution would be to use the equidistance principle, by drawing a median line between the coastlines, as has been done when proposed marine territories overlapped in the past; doing so would mean the North Pole falls to Denmark. There’s also a proposal to make the pole international, like Antarctica, as a sign of peace, says Oran Young, a political scientist at the University of California, Santa Barbara. “It seems a very sensible idea.”

    See the full article here .


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  • richardmitnick 12:11 pm on June 23, 2019 Permalink | Reply
    Tags: "Bright spots shine light on the future of coral reefs", James Cook University Australia, , Oceanography   

    From James Cook University Australia: “Bright spots shine light on the future of coral reefs” 

    From James Cook University Australia

    16 June 2016

    Josh Cinner
    mobile +61 417714138 –
    email: joshua.cinner@jcu.edu.au

    Nick Graham
    Office: +44 1524 595054
    Mobile: +44 7479438914
    Email: nick.graham@lancaster.ac.uk

    Christina Hicks
    Office: +44 1524 595089
    Mobile: +44 7479434791
    Email: christina.hicks@lancaster.ac.uk

    For further details contact:

    Kylie Simmonds, Communications Manager
    ARC Centre of Excellence for Coral Reef Studies
    Phone: +61 (0)7 4781 6067, +61 (0)428 785 895
    Email: kylie.simmonds1@jcu.edu.au

    1
    Coral reef. Pic: Tane Sinclair-Taylor tanesinclair-taylor.com

    Researchers have discovered a handful of ‘bright spots’ among the world’s embattled coral reefs, offering the promise of a radical new approach to conservation.

    In one of the largest global studies of its kind [Nature], researchers conducted over 6,000 reef surveys in 46 countries and discovered 15 ‘bright spots’ – places where, against all odds, there were a lot more fish on coral reefs than expected.

    “Given the widespread depletion of coral reef fisheries globally, we were really excited to find these bright spots that were fairing much better than we anticipated,” says lead author Professor Josh Cinner from the ARC Centre of Excellence for Coral Reef Studies at James Cook University.

    “These ‘bright spots’ are reefs with more fish than expected based on their exposure to pressures like human population, poverty, and unfavourable environmental conditions.

    “To be clear, bright spots are not necessarily pristine reefs, but rather reefs that have more fish than they should, given the pressures they face.

    “We wanted to know why these reefs could ‘punch above their weight’ so to speak, and whether there are lessons we can learn about how to avoid the degradation often associated with overfishing.”

    Co-author, Professor Nick Graham of Lancaster University says globally, coral reefs are in decline and current strategies for preserving them are insufficient.

    “Our bright spots approach has identified places we did not previously know were so successful, and the really interesting thing is that they are not necessarily untouched by man,” he says.

    “We believe their discovery offers the potential to develop exciting new solutions for coral reef conservation.”

    “Importantly, the bright spots had a few things in common, which, if applied to other places, might help promote better reef conditions.”

    “Many bright spots had strong local involvement in how the reefs were managed, local ownership rights, and traditional management practices,” says co-author Dr. Christina Hicks of Lancaster and Stanford Universities.

    The scientists also identified 35 ‘dark spots’ – these were reefs with fish stocks in worse shape than expected.

    “Dark spots also had a few defining characteristics; they were subject to intensive netting activities and there was easy access to freezers so people could stockpile fish to send to the market,” says Dr. Hicks.

    This type of bright spots analysis has been used in fields such as human health to improve the wellbeing of millions of people. It is the first time it has been rigorously developed for conservation.

    “We believe that the bright spots offer hope and some solutions that can be applied more broadly across the world’s coral reefs,” says Prof. Cinner.

    “Specifically, investments that foster local involvement and provide people with ownership rights can allow people to develop creative solutions that help defy expectations of reef fisheries depletion.

    “Conversely, dark spots may highlight development or management pathways to avoid.”

    Bright spots were typically found in the Pacific Ocean in places like the Solomon Islands, parts of Indonesia, Papua New Guinea and Kiribati. Dark spots were more globally distributed and found in every major ocean basin.

    The study has been published in the journal Nature. 39 scientists from 34 different universities and conservation groups conducted the research.

    See the full article here .

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    James Cook University (JCU) is a public university in North Queensland, Australia. The second oldest university in Queensland, JCU is a teaching and research institution. The University’s main campuses are located in the tropical cities of Cairns, Singapore and Townsville. JCU also has study centres in Mount Isa, Mackay and Thursday Island. A Brisbane campus, operated by Russo Higher Education, delivers undergraduate and postgraduate courses to international students. The University’s main fields of research include marine sciences, biodiversity, sustainable management of tropical ecosystems, genetics and genomics, tropical health care, tourism and engineering.

     
  • richardmitnick 9:38 am on June 18, 2019 Permalink | Reply
    Tags: , A NASA satellite image in August 2016 drew public attention to a 33000-square-kilometer (13000-square-mile) gap that appeared for three weeks., An area the size of New Zealand remained ice-free through three consecutive Antarctic winters despite air temperatures far below freezing., An even bigger gap of 50000 square kilometers (19000 square miles) appeared in September and October of 2017., , , Oceanography, Polynya-large hole in the sea ice, SOCCOM-Southern Ocean Carbon and Climate Observations and Modeling, The Southern Ocean is thought to play a key role in global ocean currents and carbon cycles but its behavior is poorly understood.,   

    From University of Washington: “Mysterious holes in Antarctic sea ice explained by years of robotic data” 

    U Washington

    From University of Washington

    June 10, 2019
    Hannah Hickey

    1
    The hole in the sea ice offshore of the Antarctic coast as seen by a NASA satellite on Sept. 25, 2017.NASA Worldview/NASA Blue Marble

    The winter ice on the surface of Antarctica’s Weddell Sea occasionally forms an enormous hole. A hole that appeared in 2016 and 2017 drew intense curiosity from scientists and reporters. Though even bigger gaps had formed decades before, this was the first time oceanographers had a chance to truly monitor the unexpected gap in Antarctic winter sea ice.

    A new study led by the University of Washington combines satellite images of the sea ice cover, robotic drifters and even seals outfitted with sensors to better understand the phenomenon. The research explores why this hole appears in only some years, and what role it could play in the larger ocean circulation.

    The study was published June 10 in the journal Nature.

    “We thought this large hole in the sea ice — known as a polynya — was something that was rare, maybe a process that had gone extinct. But the events in 2016 and 2017 forced us to reevaluate that,” said lead author Ethan Campbell, a UW doctoral student in oceanography. “Observations show that the recent polynyas opened from a combination of factors — one being the unusual ocean conditions, and the other being a series of very intense storms that swirled over the Weddell Sea with almost hurricane-force winds.”

    A “polynya,” a Russian word that roughly means “hole in the ice,” can form near shore as wind pushes the ice around. But it can also appear far from the coast and stick around for weeks to months, where it acts as an oasis for penguins, whales and seals to pop up and breathe.

    2
    Satellite images from Aug. 30, 2017 through Dec. 2, 2017 show the rarely-seen opening in the late Southern Hemisphere winter sea ice. The two plus signs show the location of oceanographic robots that were trapped in a spinning column of water above an underwater mountain known as Maud Rise.AMSR2-ASI/University of Bremen

    This particular spot far from the Antarctic coast often has small openings and has seen large polynyas before. The biggest known polynyas at that location were in 1974, 1975 and 1976, just after the first satellites were launched, when an area the size of New Zealand remained ice-free through three consecutive Antarctic winters despite air temperatures far below freezing.

    Campbell joined the UW as a graduate student in 2016 to better understand this mysterious phenomenon. In a stroke of scientific luck, a big one appeared for the first time in decades. A NASA satellite image in August 2016 drew public attention to a 33,000-square-kilometer (13,000-square-mile) gap that appeared for three weeks. An even bigger gap, of 50,000 square kilometers (19,000 square miles) appeared in September and October of 2017.

    The Southern Ocean is thought to play a key role in global ocean currents and carbon cycles, but its behavior is poorly understood. It hosts some of the fiercest storms on the planet, with winds whipping uninterrupted around the continent in the 24-hour darkness of polar winter. The new study used observations from the Southern Ocean Carbon and Climate Observations and Modeling project, or SOCCOM, which puts out instruments that drift with the currents to monitor Antarctic conditions.

    The study also used data from the long-running Argo ocean observing program, elephant seals that beam data back to shore, weather stations and decades of satellite images.

    3
    Ocean measurements were also collected by seals swimming under the sea ice with temporary satellite tags, showing normal water conditions in the years that did not have large polynyas.Dan Costa/University of California, Santa Cruz

    “This study shows that this polynya is actually caused by a number of factors that all have to line up for it to happen,” said co-author Stephen Riser, a UW professor of oceanography. “In any given year you could have several of these things happen, but unless you get them all, then you don’t get a polynya.”

    The study shows that when winds surrounding Antarctica draw closer to shore, they promote stronger upward mixing in the eastern Weddell Sea. In that region, an underwater mountain known as Maud Rise forces dense seawater around it and leaves a spinning vortex above. Two SOCCOM instruments were trapped in the vortex above Maud Rise and recorded years of observations there.

    Analysis shows that when the surface ocean is especially salty, as seen throughout 2016, strong winter storms can set off an overturning circulation. Warmer, saltier water from the depths gets churned up to the surface, where air chills it and makes it denser than the water below. As that water sinks, relatively warmer deep water of about 1 degree Celsius (34 F) replaces it, creating a feedback loop where ice can’t reform.

    Under climate change, fresh water from melting glaciers and other sources will make the Southern Ocean’s surface layer less dense, which might mean fewer polynyas in the future. But the new study questions that assumption. Many models show that the winds circling Antarctica will become stronger and draw closer to the coast — the new paper suggests this would encourage more polynyas to form, not fewer.

    4
    Ethan Campbell (right) and Stephen Riser (second from left) with one of the SOCCOM monitoring instruments built at the UW and then released in the Southern Ocean.Dennis Wise/University of Washington

    These are the first observations to prove that even a smaller polynya like the one in 2016 moves water from the surface all the way to the deep ocean.

    “Essentially it’s a flipping over of the entire ocean, rather than an injection of surface water on a one-way trip from the surface to the deep,” said co-author Earle Wilson, who recently completed his doctorate in oceanography at the UW.

    One way that a surface polynya matters for the climate is for the deepest water in the oceans, known as Antarctic Bottom Water. This cold, dense water lurks below all the other water. Where and how it’s created affects its characteristics, and would have ripple effects on other major ocean currents.

    “Right now people think most of the bottom water is forming on the Antarctic shelf, but these big offshore polynyas might have been more common in the past,” Riser said. “We need to improve our models so we can study this process, which could have larger-scale climate implications.”

    Large and long-lasting polynyas can also affect the atmosphere, because deep water contains carbon from lifeforms that have sunk over centuries and dissolved on their way down. Once this water reaches the surface that carbon could be released.

    “This deep reservoir of carbon has been locked away for hundreds of years, and in a polynya it might get ventilated at the surface through this really violent mixing,” Campbell said. “A large carbon outgassing event could really whack the climate system if it happened multiple years in a row.”

    Other co-authors on the paper are Kent Moore at the University of Toronto, who was the 2016-17 Canada Fulbright Visiting Chair in Arctic Studies at the UW; Casey Brayton at the University of South Carolina; and Lynne Talley and Matthew Mazloff from Scripps Institution of Oceanography at the University of California, San Diego. SOCCOM is funded by the National Science Foundation. Campbell was supported by the U.S. Department of Defense through the National Defense Science & Engineering Graduate Fellowship program. Additional funding is from the NSF, the National Oceanic and Atmospheric Administration, the University of Washington and Scripps Institution of Oceanography.

    For more information, contact Campbell at ethancc@uw.edu and 224-388-0301, Riser at riser@uw.edu and 206-543-1187 or Wilson at earlew@uw.edu.

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    u-washington-campus
    The University of Washington is one of the world’s preeminent public universities. Our impact on individuals, on our region, and on the world is profound — whether we are launching young people into a boundless future or confronting the grand challenges of our time through undaunted research and scholarship. Ranked number 10 in the world in Shanghai Jiao Tong University rankings and educating more than 54,000 students annually, our students and faculty work together to turn ideas into impact and in the process transform lives and our world. For more about our impact on the world, every day.
    So what defines us —the students, faculty and community members at the University of Washington? Above all, it’s our belief in possibility and our unshakable optimism. It’s a connection to others, both near and far. It’s a hunger that pushes us to tackle challenges and pursue progress. It’s the conviction that together we can create a world of good. Join us on the journey.

     
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