Tagged: Woods Hole Oceanographic Institute Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 8:32 am on May 8, 2019 Permalink | Reply
    Tags: "North Atlantic Ocean productivity has dropped 10 percent during Industrial era", , DMS-dimethylsulfide, , , MSA-methanesulfonic acid, , Phytoplankton, The decline coincides with steadily rising surface temperatures over the same period of time., Woods Hole Oceanographic Institute   

    From MIT News: “North Atlantic Ocean productivity has dropped 10 percent during Industrial era” 

    MIT News
    MIT Widget

    From MIT News

    May 6, 2019
    Jennifer Chu

    Phytoplankton decline coincides with warming temperatures over the last 150 years.

    1
    Matt Osman, a graduate student in MIT’s Department of Earth, Atmospheric, and Planetary Sciences, overlooking a frozen Baffin Bay to the west, Nuussuaq Peninsula Ice Cap, west Greenland. Image: Luke Trusel (Rowan University).

    2
    Ice core field camp on a clear spring evening, Disko Island Ice Cap, west Greenland. Image: Luke Trusel (Rowan University).

    3
    Iceberg in Disko Bay, west Greenland. Image: Luke Trusel (Rowan University)

    4
    Retrieving an ice core section from the drill barrel during a west Greenland snowstorm, west Greenland Ice Sheet. Image: Sarah Das (WHOI).

    Virtually all marine life depends on the productivity of phytoplankton — microscopic organisms that work tirelessly at the ocean’s surface to absorb the carbon dioxide that gets dissolved into the upper ocean from the atmosphere.

    Through photosynthesis, these microbes break down carbon dioxide into oxygen, some of which ultimately gets released back to the atmosphere, and organic carbon, which they store until they themselves are consumed. This plankton-derived carbon fuels the rest of the marine food web, from the tiniest shrimp to giant sea turtles and humpback whales.

    Now, scientists at MIT, Woods Hole Oceanographic Institution (WHOI), and elsewhere have found evidence that phytoplankton’s productivity is declining steadily in the North Atlantic, one of the world’s most productive marine basins.

    In a paper appearing today in Nature, the researchers report that phytoplankton’s productivity in this important region has gone down around 10 percent since the mid-19th century and the start of the Industrial era. This decline coincides with steadily rising surface temperatures over the same period of time.

    Matthew Osman, the paper’s lead author and a graduate student in MIT’s Department of Earth, Atmospheric, and Planetary Sciences and the MIT/WHOI Joint Program in Oceanography, says there are indications that phytoplankton’s productivity may decline further as temperatures continue to rise as a result of human-induced climate change.

    “It’s a significant enough decine that we should be concerned,” Osman says. “The amount of productivity in the oceans roughly scales with how much phytoplankton you have. So this translates to 10 percent of the marine food base in this region that’s been lost over the industrial era. If we have a growing population but a decreasing food base, at some point we’re likely going to feel the effects of that decline.”

    Drilling through “pancakes” of ice

    Osman and his colleagues looked for trends in phytoplankton’s productivity using the molecular compound methanesulfonic acid, or MSA. When phytoplankton expand into large blooms, certain microbes emit dimethylsulfide, or DMS, an aerosol that is lofted into the atmosphere and eventually breaks down as either sulfate aerosol, or MSA, which is then deposited on sea or land surfaces by winds.

    “Unlike sulfate, which can have many sources in the atmosphere, it was recognized about 30 years ago that MSA had a very unique aspect to it, which is that it’s only derived from DMS, which in turn is only derived from these phytoplankton blooms,” Osman says. “So any MSA you measure, you can be confident has only one unique source — phytoplankton.”

    In the North Atlantic, phytoplankton likely produced MSA that was deposited to the north, including across Greenland. The researchers measured MSA in Greenland ice cores — in this case using 100- to 200-meter-long columns of snow and ice that represent layers of past snowfall events preserved over hundreds of years.

    “They’re basically sedimentary layers of ice that have been stacked on top of each other over centuries, like pancakes,” Osman says.

    The team analyzed 12 ice cores in all, each collected from a different location on the Greenland ice sheet by various groups from the 1980s to the present. Osman and his advisor Sarah Das, an associate scientist at WHOI and co-author on the paper, collected one of the cores during an expedition in April 2015.

    “The conditions can be really harsh,” Osman says. “It’s minus 30 degrees Celsius, windy, and there are often whiteout conditions in a snowstorm, where it’s difficult to differentiate the sky from the ice sheet itself.”

    The team was nevertheless able to extract, meter by meter, a 100-meter-long core, using a giant drill that was delivered to the team’s location via a small ski-equipped airplane. They immediately archived each ice core segment in a heavily insulated cold storage box, then flew the boxes on “cold deck flights” — aircraft with ambient conditions of around minus 20 degrees Celsius. Once the planes touched down, freezer trucks transported the ice cores to the scientists’ ice core laboratories.

    “The whole process of how one safely transports a 100-meter section of ice from Greenland, kept at minus-20-degree conditions, back to the United States is a massive undertaking,” Osman says.

    Cascading effects

    The team incorporated the expertise of researchers at various labs around the world in analyzing each of the 12 ice cores for MSA. Across all 12 records, they observed a conspicuous decline in MSA concentrations, beginning in the mid-19th century, around the start of the Industrial era when the widescale production of greenhouse gases began. This decline in MSA is directly related to a decline in phytoplankton productivity in the North Atlantic.

    “This is the first time we’ve collectively used these ice core MSA records from all across Greenland, and they show this coherent signal. We see a long-term decline that originates around the same time as when we started perturbing the climate system with industrial-scale greenhouse-gas emissions,” Osman says. “The North Atlantic is such a productive area, and there’s a huge multinational fisheries economy related to this productivity. Any changes at the base of this food chain will have cascading effects that we’ll ultimately feel at our dinner tables.”

    The multicentury decline in phytoplankton productivity appears to coincide not only with concurrent long-term warming temperatures; it also shows synchronous variations on decadal time-scales with the large-scale ocean circulation pattern known as the Atlantic Meridional Overturning Circulation, or AMOC. This circulation pattern typically acts to mix layers of the deep ocean with the surface, allowing the exchange of much-needed nutrients on which phytoplankton feed.

    In recent years, scientists have found evidence that AMOC is weakening, a process that is still not well-understood but may be due in part to warming temperatures increasing the melting of Greenland’s ice. This ice melt has added an influx of less-dense freshwater to the North Atlantic, which acts to stratify, or separate its layers, much like oil and water, preventing nutrients in the deep from upwelling to the surface. This warming-induced weakening of the ocean circulation could be what is driving phytoplankton’s decline. As the atmosphere warms the upper ocean in general, this could also further the ocean’s stratification, worsening phytoplankton’s productivity.

    “It’s a one-two punch,” Osman says. “It’s not good news, but the upshot to this is that we can no longer claim ignorance. We have evidence that this is happening, and that’s the first step you inherently have to take toward fixing the problem, however we do that.”

    This research was supported in part by the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), as well as graduate fellowship support from the US Department of Defense Office of Naval Research.

    See the full article here .


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


    Stem Education Coalition

    MIT Seal

    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

    MIT Campus

     
  • richardmitnick 10:08 am on September 27, 2018 Permalink | Reply
    Tags: , , , , Rutgers Receives NSF Award to Continue Pioneering Ocean Initiative, , , Woods Hole Oceanographic Institute   

    From Rutgers University: “Rutgers Receives NSF Award to Continue Pioneering Ocean Initiative” 

    Rutgers smaller
    Our Great Seal.

    From Rutgers University

    September 25, 2018

    Dalya Ewais
    848-445-3153
    dalya.ewais@rutgers.edu

    The project delivers insight to researchers, policymakers and the public worldwide.

    The National Science Foundation this week announced it has awarded a five-year, $220 million contract to a coalition of academic and oceanographic research organizations, including Rutgers University–New Brunswick, to operate and maintain the Ocean Observatories Initiative [OOI].

    The coalition, led by the Woods Hole Oceanographic Institution with direction from the NSF, includes Rutgers, the University of Washington and Oregon State University.

    1

    The initiative includes platforms and sensors that measure physical, chemical, geological and biological properties and processes from the seafloor to the sea surface in key coastal and open-ocean sites of the Atlantic and Pacific. It was designed to address critical questions about the Earth-ocean system, including climate change, ecosystem variability, ocean acidification plate-scale seismicity and submarine volcanoes, and carbon cycling. The goal is to better understand the ocean and our planet.

    3
    The seafloor cable extends off the coast of Oregon and allows real-time communication with the deep sea. University of Washington

    Each institution will continue to operate and maintain the portion of project’s assets for which it is currently responsible. Rutgers will operate the cyberinfrastructure system that ingests and delivers data for the initiative.

    The initiative supports more than 500 autonomous instruments on the seafloor and on moored and free-swimming platforms that are serviced during regular, ship-based expeditions to the array sites. Data from each instrument is transmitted to shore, where it is freely available to users worldwide, including scientists, policy experts, decision-makers, educators and the general public.

    “Rutgers is proud to be a part of this transformative project that provides scientists and educators across the globe access to the richest source of real-time, in-water oceanographic data,” said David Kimball, interim senior vice president for research and economic development at Rutgers.

    Over the last three years, the Rutgers team led by Manish Parashar, director of the Rutgers Discovery Informatics Institute and Distinguished Professor of computer science, designed, built and operated the OOI’s cyberinfrastructure. The team also included Scott Glenn and Oscar Schofield, Distinguished Professors in the Department of Marine and Coastal Sciences and co-founders of Rutgers’ Center for Ocean Observing Leadership, who led the Rutgers data team.

    3
    From left to right: Manish Parashar, director of the Rutgers Discovery Informatics Institute and Distinguished Professor of computer science; Peggy Brennan-Tonetta, associate vice president for economic development at Rutgers’ Office of Research and Economic Development; and Ivan Rodero, project manager.
    Photo: Nick Romanenko/Rutgers University

    For the second phase of the OOI project, which begins on October 1 and runs for five years, Rutgers will receive about $6.6 million and will be responsible for maintaining the cyberinfrastructure and providing a network that allows 24/7 connectivity, ensuring sustained, reliable worldwide ocean observing data any time, any place, on any computer or mobile device. Peggy Brennan-Tonetta, associate vice president for economic development at Rutgers’ Office of Research and Economic Development, will serve as acting principal investigator.

    “Greater awareness and knowledge of the state of our oceans and the effects of their interrelated systems today is critical to a deeper understanding of our changing climate, marine and coastal ecosystems, atmospheric exchanges, and geodynamics. We are pleased to continue our involvement with this project that enables researchers to better understand the state of our oceans,” Brennan-Tonetta said.

    See the full article here .


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

    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 10:28 am on January 15, 2018 Permalink | Reply
    Tags: , , , , Woods Hole Oceanographic Institute   

    From COSMOS: “Underwater eruption largest in living memory” 

    Cosmos Magazine bloc

    COSMOS Magazine

    15 January 2018
    Andrew Masterson

    US-Australian team find surprises and complexity at Pacific ocean volcano site.

    1
    A remotely operated vehicle (ROV) lands on the seafloor at Havre submarine volcano to retrieve a heat flow monitor. Woods Hole Oceanographic Institute.

    The first close quarters investigation of what was possibly the largest underwater volcanic eruption in modern history has uncovered a carpet of pumice rocks, some as big as motor vehicles, and unexpected ocean-bed lava flows.

    In a paper published in the journal Science Advances, a research team led by the University of Tasmania in Australia and the Woods Hole Oceanographic Institution (WHOI) in the US report on the use of two autonomous underwater vehicles to explore the aftermath of the eruption of the 2012 Harve volcano, which lies between New Zealand and American Samoa in the southwest Pacific Ocean.

    The volcano blew on July 18, 2012, an event noted only when passengers on an airliner flying above the Kermadec Islands (of which Harve is an underwater component) noticed a huge number of pumice rocks floating on the surface of the ocean. The raft of rocks eventually covered almost 400 square kilometres.

    Three years later, the joint Australian-US expedition headed to the blast site.

    “We knew it was a large-scale eruption, approximately equivalent to the biggest eruption we’ve seen on land in the Twentieth Century,” says Australian volcanologist Rebecca Carey, and co-chief scientist on the expedition.

    Carey and her colleagues suspected they would find evidence of a deep-sea explosive eruption – the commonest form of underwater volcanic activity – but what they discovered was different.

    Instead of the classic blast pattern associated with explosive eruptions, they saw an ocean floor littered with large lumps. So unusual was the find that at first co-author Adam Soule from WHOI thought something had gone wrong with the autonomous vehicles’ imaging system.

    “It turned out that each bump was a giant block of pumice, some of them the size of a van,” he says. “I had never seen anything like it on the seafloor.”

    Having gathered as much evidence as possible, the team concluded that the Harve volcano had undergone an underwater silicic eruption, characterised by the forceful emission of viscous, gas-filled lava.

    This made for an exciting find. Very little is known about silicic eruptions. They are extremely violent acts, but because they take place deep underwater in vast oceans they are very rarely recorded. Most of the current knowledge about their behaviour comes from geologic records rather than observation.

    Already, the team’s findings are adding considerably to the picture. The Harve eruption, they discovered, was a complex affair, with lava emerging from 14 vents, between 900 and 1220 metres below sea level.

    While explosive eruptions produce mainly pumice, this one also produced significant amounts of ash, lava flows and lava domes.

    Although an estimated 75% of the erupted material headed to the sea surface and eventually floated away, that which remained underwater was enough to spread across the ocean floor for several kilometres.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: