Rabu, 30 September 2020

Arctic sea ice reaches second lowest extent on record - KSLA

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Sea ice reflects much of the sun’s radiation back into space, whereas dark, ice-free ocean water absorbs more of the sun’s energy and this can lead to disruptions in the jet stream leading to that can cause extreme weather patterns such as heat waves and extreme winters, sea level rise, coastal erosion, and disruption for coastal arctic communities.

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October 01, 2020 at 05:20AM
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Arctic sea ice reaches second lowest extent on record - KSLA

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Colombian woman, who was missing for 2 years, found alive at sea - FOX 4 Dallas

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Fisherman off the coast of Colombia thought they’d spotted a log in the distance on Sept. 26.

They quickly realized it was a person once the woman raised her arms.

Rolando Visbal, one of the fishermen, called out to her in English and Spanish. But she’d been in the cold water too long to respond.

Once she received medical treatment at a hospital, she identified herself as 46-year-old Angelica Gaitan, a woman who had been missing for two years.

A Colombian woman who had fallen off the grid two years ago was miraculously discovered alive at sea by fishermen. (Credit: Rolando Visbal via Storyful)

According to La Libertad, she escaped an abusive relationship in September 2018 and wandered the streets for six months before looking for help at a women’s center in Barranquilla.

The shelter provided her protection from her ex-partner. But on Sept. 25, Gaitan learned her former partner no longer lived in the area, so she’d have to leave.

At that point, Gaitan decided to end her life.

"Being on the seashore I found myself alone and in solitude; I decided to jump into the sea and let it take me," she told local media. "I just had to hope this nightmare would soon be over."

Gaitan floated in the ocean for hours, but she said she has no memory of it.

She’s grateful to have been rescued, hoping to make the best of her second chance at life.

"I feel like I was born again, thank God. If I had had an opportunity or help I would not make that decision. Now I am very grateful because God gave me a new opportunity to move forward," Gaitan explained.

___

If you or a loved one is feeling distressed, call the National Suicide Prevention Lifeline. The crisis center provides free and confidential emotional support 24 hours a day, 7 days a week to civilians and veterans. Call the National Suicide Prevention Lifeline at 1-800-273-8255. Or text HOME to 741-741 (Crisis Text Line)

CLICK HERE for the warning signs and risk factors of suicide. Call 1-800-273-TALK for free and confidential emotional support.

___

This story was reported from Atlanta. 

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September 30, 2020 at 09:09PM
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Colombian woman, who was missing for 2 years, found alive at sea - FOX 4 Dallas

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Tropical wave developing in Caribbean Sea - Monitor

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The National Hurricane Center is monitoring a tropical wave over the west-central Caribbean Sea that could develop into something more serious in the next five days.

But forecasters say it is too early to know whether the wave will have any kind of impact on South Texas or the Rio Grande Valley.

The tropical wave is expected to move westward over the next couple of days and interact with a frontal system, producing low pressure over the western Caribbean Sea later this week.

A tropical depression could form over the weekend while the system moves slowly west-northwestward over the northwestern Caribbean Sea.

Diana Eva Maldonado is the Digital Editor for the Brownsville Herald, Valley Morning Star and Coastal Current. She can be reached at dmaldonado@valleystar.com or (956) 421-9872 or (956) 982-6618.

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October 01, 2020 at 04:34AM
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Tropical wave developing in Caribbean Sea - Monitor

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The grim truth behind eyewitness accounts of sea serpents - Nature.com

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Painted panorama of Gloucester harbor and the sea serpent by John Ritto Penniman, from a drawing made by Captain John Beach.

Hundreds of people in the nineteenth-century United States reported seeing the Gloucester Sea Serpent (above), which was probably a marine creature bedecked with fishing debris. Credit: Museum of Fine Arts, Boston

Fisheries

Centuries-old ‘unidentified marine objects’ hint that sea creatures have been getting entangled in fishing lines since before the invention of plastic.

‘Sea serpents’ spotted around Great Britain and Ireland in the nineteenth century were probably whales and other marine animals ensnared in fishing gear — long before the advent of the plastic equipment usually blamed for such entanglements.

The snaring of sea creatures in fishing equipment is often considered a modern phenomenon, because the hemp and cotton ropes used in the past degraded more quickly than their plastic counterparts. But Robert France at Dalhousie University in Truro, Canada, identified 51 probable entanglements near Great Britain and Ireland dating as far back as 1809.

France analysed 214 accounts of ‘unidentified marine objects’ from the early nineteenth century to 2000, looking for observations of a monster that had impressive length, a series of humps protruding above the sea surface and a fast, undulating movement through the water. France says that such accounts describe not sea serpents but whales, basking sharks (Cetorhinus maximus) or other marine animals trailing fishing gear such as buoys or other floats.

Such first-hand accounts could help researchers to construct a better picture of historical populations of marine species and the pressures they faced, France says.

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September 30, 2020 at 08:34PM
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The grim truth behind eyewitness accounts of sea serpents - Nature.com

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Colombian woman, who was missing for 2 years, found alive at sea - FOX 10 News Phoenix

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Fisherman off the coast of Colombia thought they’d spotted a log in the distance on Sept. 26.

They quickly realized it was a person once the woman raised her arms.

Rolando Visbal, one of the fishermen, called out to her in English and Spanish. But she’d been in the cold water too long to respond.

Once she received medical treatment at a hospital, she identified herself as 46-year-old Angelica Gaitan, a woman who had been missing for two years.

A Colombian woman who had fallen off the grid two years ago was miraculously discovered alive at sea by fishermen. (Credit: Rolando Visbal via Storyful)

According to La Libertad, she escaped an abusive relationship in September 2018 and wandered the streets for six months before looking for help at a women’s center in Barranquilla.

The shelter provided her protection from her ex-partner. But on Sept. 25, Gaitan learned her former partner no longer lived in the area, so she’d have to leave.

At that point, Gaitan decided to end her life.

"Being on the seashore I found myself alone and in solitude; I decided to jump into the sea and let it take me," she told local media. "I just had to hope this nightmare would soon be over."

Gaitan floated in the ocean for hours, but she said she has no memory of it.

She’s grateful to have been rescued, hoping to make the best of her second chance at life."I feel like I was born again, thank God. If I had had an opportunity or help I would not make that decision. Now I am very grateful because God gave me a new opportunity to move forward," Gaitan explained.

___

If you or a loved one is feeling distressed, call the National Suicide Prevention Lifeline. The crisis center provides free and confidential emotional support 24 hours a day, 7 days a week to civilians and veterans. Call the National Suicide Prevention Lifeline at 1-800-273-8255. Or text HOME to 741-741 (Crisis Text Line)

CLICK HERE for the warning signs and risk factors of suicide. Call 1-800-273-TALK for free and confidential emotional support.

___

This story was reported from Atlanta. 

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September 30, 2020 at 09:09PM
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Colombian woman, who was missing for 2 years, found alive at sea - FOX 10 News Phoenix

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Implications of Sea Ice Management for Arctic Biogeochemistry - Eos

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As the world faces the reality of anthropogenic global warming, substantial human ingenuity is being directed not only toward mitigating and adapting to the changes occurring on our planet but also toward direct, technological interventions in the climate system—geoengineering. Most geoengineering proposals fall into one of two categories: negative emission technologies that remove carbon dioxide (CO2) from the atmosphere and solar radiation management technologies that increase the amount of sunlight reflected by Earth, the planetary albedo. Some solar radiation management proposals suggest raising the albedo of the Arctic Ocean by restoring lost sea ice, which would shield the ocean below and limit its absorption of solar radiation.

Two proposals to artificially restore Arctic sea ice have received particular attention. One suggests thickening sea ice by pumping seawater onto the top of the ice in winter, an approach we will call “flooding” [Desch et al., 2017]. The low air temperatures would quickly freeze that water, thickening the ice faster than it would grow naturally, and the resulting thicker sea ice cover would better withstand summer melt. In contrast, Field et al. [2018] propose spreading highly reflective glass microspheres as a form of artificial snow on the sea ice, which would sufficiently increase its albedo to reduce melt.

Given the fundamentally invasive nature of these climate intervention proposals, the scientific community must thoroughly investigate and discuss the consequences to inform policy decisions on whether and how to proceed [Boyd and Vivian, 2019]. To date, discussions of the potential efficacy and impacts of sea ice restoration have focused on the physics of the radiative balance [Zampieri and Goessling, 2019], impacts on fish and birds, the economics and industrial carbon footprints of broad implementation, and reversibility—that is, how quickly the effects of an intervention would be reversed if the deployment were halted. Those issues are certainly important, but amid the discussions, the potentially substantial effects on biogeochemistry in the sea ice, the underlying water, and the overlying atmosphere—and whether these effects too would be reversible—have received little attention.

Living and Breathing Sea Ice

Sea ice is a complex and biogeochemically active medium, with channels and pockets of concentrated brine containing highly adapted biological communities [Thomas, 2017]. As sea ice freezes and melts through its annual cycle, it exchanges material with both the atmosphere and underlying waters [Vancoppenolle et al., 2013]. During initial freeze-up, young ice is extremely permeable, and biological and geochemical processes within ice brines release CO2 and aerosol precursors. As winter advances, the ice thickens. Brine drainage coupled with lower temperatures reduces the permeability of the upper ice, and biological communities become concentrated at the bottom of the sea ice. During spring, the ice again becomes more permeable as melt advances, accelerating material exchanges with the atmosphere and the water while algal communities in and under the sea ice bloom, fundamentally contributing to the entire Arctic Ocean ecosystem [Wassmann and Reigstad, 2011].

Sea ice is also nearly always covered with snow, except in high summer. Because it absorbs salt from the underlying ice, natural snow atop sea ice is always at least somewhat salty and is highly chemically reactive, which makes it an important source of aerosols to the atmosphere [Abbatt et al., 2012]. When the ice surface is flooded with seawater, which occurs naturally when a thick snow cover accumulates on thin ice, typical sea ice is not produced, but rather a mixture called “snow ice” is. The structure of snow ice is quite different from that of either upper sea ice or snow, and their permeabilities follow different trajectories through formation and melting, affecting material exchanges with the atmosphere.

Sea ice restoration approaches like seawater flooding and artificial snow would affect numerous interacting systems.
Fig. 1. Sea ice restoration approaches like seawater flooding and artificial snow would affect solar radiation absorption (yellow arrows), gas and aerosol fluxes (red arrows), brine release (purple arrows), and primary production (green, in both ice and water) in the Arctic.

The seasonal evolution of sea ice and its interfaces with the air and water are thus fundamental in polar and global biogeochemical cycles. The proposals to artificially increase sea ice thickness would alter the radiative, thermal, structural, and chemical characteristics of the ice, with consequences for the biogeochemistry and ecology of the sea ice, the ocean, and the atmosphere (Figure 1).

Gases and Aerosols

Both flooding and artificial snow in the form of glass beads would change the release of reactive substances from sea ice into the Arctic atmosphere, in particular, halogen (e.g., bromide from sea salt or methyl iodide from algae [Abbatt et al., 2012]) and sulfur (e.g., dimethyl sulfide from algae) compounds. These emissions affect atmospheric chemistry and aerosol loading. Flooding could result in large biological communities at the top of the ice (as often occurs naturally in Antarctic sea ice), and such surface communities may release reactive material to the atmosphere. On the other hand, inert, artificial snow could decrease the overall aerosol source to the atmosphere by dampening gas fluxes to the atmosphere from the underlying sea ice.

In the absence of sunlight, an increase in atmospheric aerosols would warm the winter Arctic atmosphere, and conversely, a decrease in aerosols would cool temperatures [Willis et al., 2018]. However, with a seasonal increase in light and photochemical reactivity, matters become much more complicated, and both aerosol and gaseous halogen chemistry could have myriad contrasting impacts on the Arctic atmosphere. For example, halogens released from freezing sea ice are associated with ozone depletion and mercury deposition events [Simpson et al., 2007]. Changes in the timing and locations of those emissions have implications for mercury contamination in Arctic food webs.

Artificial snow cover would also dampen CO2 fluxes between sea ice and the atmosphere and would thermally insulate the ice, reducing the freezing rate at the bottom and limiting CO2 injection into the underlying water. In contrast, wintertime flooding would initially increase CO2 release to the atmosphere because rapid, low-temperature freezing would increase salinity and decrease CO2 solubility in the resulting brines [Vancoppenolle et al., 2013]. This CO2 emission would likely be larger than that which occurs during natural autumn freezing both because of lower temperatures and because CO2 release to the underlying water would be blocked by the established, relatively thick, and impermeable ice cover. On the other hand, flooding and the formation of snow ice would also increase the total thermal conductivity of the ice column, thereby increasing basal freezing and, potentially, CO2 release to the water. In addition, snow ice resulting from flooding would severely limit atmospheric CO2 drawdown into the ice well into the spring melt period.

Light and Life

Snow on sea ice not only affects the heat absorbed by the ice but also very strongly controls the light available for photosynthesis in sea ice and oceanic ecosystems [Leu et al., 2015]. High-albedo artificial snow could delay the onset and reduce the magnitude of algal blooms both within and under the sea ice. The timing and magnitude of these blooms have direct consequences for community structure and the life cycles of zooplanktonic grazers, with cascading impacts on Arctic Ocean ecosystems [Falk-Petersen et al., 2007] and the biological CO2 sink. The optical properties of artificial snow and its interactions with natural snow (e.g., impacts on snow metamorphosis, which would also influence gas fluxes) could increase or decrease the light available for primary production. Algae introduced to the top of sea ice by flooding would shade and delay growth of algae at the bottom of the ice and in the water beneath, reducing food available to grazers.

Perhaps one of the most wide-ranging impacts of deploying artificial snow composed of glass beads would be the potential to fertilize oceanic ecosystems with silicon. Silicon fertilization, particularly when coupled with changes in the timing of sea ice melt and surface water stratification, could have a substantial impact on spring bloom dynamics and community succession.

Local and Distant Feedbacks

In evaluating climate intervention proposals, we must also consider local biogeochemical effects of the industrial-scale infrastructure that would be required to implement the interventions. The positioning of large numbers of massive seawater pumps needed for flooding, ice cover disruption by ships deployed to spread artificial snow, and the aerosol emissions from those ships would also affect the biogeochemistry and ecology of Arctic systems.

Many of the processes we have identified would have opposing impacts on the climate system and on biogeochemical cycles. Furthermore, sea ice can travel long distances, so the biogeochemical impacts of interventions could accumulate far from deployment sites. In total, it is clear that sea ice and its interactions with the atmosphere and the ocean are highly complex, and biogeochemical feedbacks in these systems are much less predictable than the radiative balance.

Look Before You Leap

In the face of widespread anthropogenic impacts on the global Earth system, humanity has a responsibility to consider and investigate ways to limit the damage. However, Earth is a complex system, and the law of unintended consequences is incontrovertible. Dependable predictions of the total effects of artificial sea ice restoration approaches are currently unavailable and require extensive further research. Laboratory, numerical, and possibly field experiments need to focus both on detailed processes, such as the dissolution of glass microbeads and potential sintering between glass and ice, and on how natural systems will respond over wide areas and long time periods, for example, with respect to carbon export into deep waters and silicon fertilization.

Any interventions to alter the progress of climate change will have repercussions throughout the environment. In the worst-case scenario, the time may come when the global community decides that some geoengineering cures are preferable to the climate change disease. However, discussions about implementing intentional climate interventions must examine all possible side effects in depth and with clarity. As a contribution to that multidisciplinary discussion of potential climate interventions, we encourage the polar science research community to assess in detail the biogeochemical consequences of artificial Arctic sea ice restoration.

Acknowledgments

This article arose from the Biogeochemical Exchange Processes at Sea Ice Interfaces (BEPSII) steering committee, and we thank the entire BEPSII community for all our discussions and insights into sea ice and its contributions to global biogeochemical cycles. BEPSII thanks the Climate and Cryosphere program, the Scientific Committee on Antarctic Research, and the Surface Ocean-Lower Atmosphere Study for their generous and sustained support.

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September 30, 2020 at 07:12PM
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Implications of Sea Ice Management for Arctic Biogeochemistry - Eos

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US, Ukrainian Navies Conduct Drills in the Black Sea - USNI News - USNI News

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USS Roosevelt (DDG-80) enters the Black Sea on September 15, 2020. Photo by Yörük Işık‏ used with permission.

Destroyer USS Roosevelt (DDG-80) performed drills in the Black Sea with the Ukrainian navy on Tuesday, the U.S. Navy announced.

Ukraine’s Island-class cutter Starobilsk (P191) and the Gurza-M class (Project 58155) gunboats Nikopol (P176) and Kastopol (P180) participated in the exercise, according to a Navy press release. Starobilsk is a former U.S. Coast Guard cutter that was transported to Ukraine last year in an effort to bolster the Ukrainian Naval Forces, USNI News previously reported.

An MH-60R Seahawk helicopter attached to Roosevelt and Ukraine’s Mil MI-14 helicopter also joined for the Black Sea drills, according to the news release.

“Conducting exercises with our Ukrainian NATO partners demonstrates the combined strength and capacity that is always resident when our two nation’s navies come together. The U.S. – Ukraine partnership that has existed for decades has never been stronger,” Cmdr. Ryan Kendall, the commanding officer of Roosevelt, said in a statement.

“The Ukrainian Navy is a professional organization with a lot of capability and skillsets that challenge my team to operate at our peak proficiency, it was a true pleasure working with their naval team in the Black Sea,” he continued.

Roosevelt’s transit into the Black Sea for the exercise marks the sixth trip for a Navy vessel to the body of water this year, the service said.

“The passing exercise served as an opportunity for the U.S. and Ukrainian naval forces to refine ship handling and maneuvering capabilities,” the Navy said. “U.S. Navy vessels routinely conduct training with NATO Allies and partners in order to enhance collaboration and increase capacity in order to strengthen the regional maritime security.”

The U.S. Navy in July conducted the Sea Breeze 2020 exercise in the Black Sea with seven other nations, including Ukraine. Shortly before the exercise started, the Russian navy reportedly disclosed plans to perform snap drills in the Black Sea.

Speaking to reporters in the midst of the Sea Breeze exercise, a commanding officer of a U.S. destroyer participating in the drills said the service was on “higher alert” due to Russian activity in the waters.

“There’s definitely Russian presence up here. There hasn’t been any confrontation. Every interaction I’ve had with them has been safe and professional,” Cmdr. Craig Trent, the commanding officer of destroyer USS Porter (DDG-78), told reporters during a July 22 virtual roundtable.

“They’re definitely present. They’re definitely watching us,” he added. “We’re watching them. … If anything ever does become unsafe or unprofessional, that’s something that we’re ready to take action to make sure that we are safe.”

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September 30, 2020 at 05:20AM
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Military cargo plane, fighter jet collide near Salton Sea - Los Angeles Times

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A military KC-130 cargo plane collided with a fighter jet Tuesday afternoon over Imperial County, according to the United States Marine Corps and the California Highway Patrol.

At about 4 p.m., an F-35B jet made contact with the cargo plane during an air-to-air refueling effort, causing the jet to crash, the Marine Corps said in a statement. The jet’s pilot — its sole occupant — ejected from the craft and is being treated for injuries that are not life threatening, 1st Lt. Brett Vannier said.

The cargo plane made an emergency landing in a nearby farm area and is now at an airport in Thermal. All eight crew members of the cargo plane are safe, Vannier said.

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Emergency personnel were on the scene. KYMA-TV reported that there were fires around the site of the crash.

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September 30, 2020 at 07:54AM
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Military cargo plane, fighter jet collide near Salton Sea - Los Angeles Times

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Two Marine Corps aircraft collide mid-air near Salton Sea - The San Diego Union-Tribune

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A Marine Corps F-35B collided with a KC-130J while conducting mid-air refueling somewhere over the Southern California desert Tuesday afternoon, according to the Marines.

The F-35B pilot ejected safely while the KC-130J made an emergency landing on its belly in a field near the Jacqueline Cochran Regional Airport near Thermal, Ca., which is just north of Salton Sea, according to a Marine Corps Air Station Yuma spokesman.

Eight crewmembers were on board the KC-130J and all are reported safe, the Marines said.

Both aircraft were operating out of MCAS Yuma, but the Marines declined to say whether the base is each aircraft’s permanent operating base.

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The collision occurred around 4 p.m. Tuesday. The Marines declined to provide more details about the location of the collision or where the F-35B wreckage landed.

The F-35B is the Marine Corps’ newest short takeoff vertical landing fighter. The KC-130J is a mid-air refueling tanker.

The crash is under investigation, and updates will be provided as more information becomes available, the Marines said.

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September 30, 2020 at 09:21AM
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Two Marine Corps aircraft collide mid-air near Salton Sea - The San Diego Union-Tribune

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Selasa, 29 September 2020

Marine biodiversity reshuffles under warmer and sea ice-free Pacific Arctic - Science Daily

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Climate warming will alter marine community compositions as species are expected to shift poleward, significantly impacting the Arctic marine ecosystem.

The biodiversity of marine communities in the Pacific Arctic under future climate change scenarios highlights profound changes relative to their present patterns. Alterations in marine species distributions in response to warming and sea ice reduction are likely to increase the susceptibility and vulnerability of Arctic ecosystems. The findings, published by Hokkaido University researchers in the journal Science of the Total Environment, also suggest that there will be potential impacts on the ecosystem function and services.

Fisheries oceanographer Irene Alabia of Hokkaido University's Arctic Research Center along with colleagues in Japan and the US investigated how future climate changes will impact the marine biodiversity in the Bering and Chukchi Seas. These seas extend from Alaska to Russia in the northern Pacific and southern Arctic oceans.

"This area forms a 'biogeographical transition zone': a biodiversity-rich region covering two distinct areas with specific features that encourage the coexistence of species living at or close to their distribution limits," explains Alabia. "These zones are vulnerable to climate warming, and climatic disruptions can create favorable conditions for the shift of warm-water species into previously colder-water zones."

Scientists are interested in understanding how species in biogeographical transition zones are responding to climate changes and other human impacts. This information could help in conservation planning, fisheries management, and in studying the role of evolutionary history in shaping currently existing communities.

Alabia and her team mapped the present and future spatial distributions of 26 fish and invertebrate species in the Bering and Chukchi Seas. Using species records, sea surface temperature, and sea ice concentration data, the authors developed species distribution models to predict the distributional ranges under the present-day (1993-2017) and future (2026-2100) climate conditions. From the model outputs, the changes in species richness and compositional diversity in terms of species' phylogeny and functional traits between time periods and across contrasting levels of warming were elucidated.

The findings suggest that larger, longer-lived and more predatory fish and invertebrates will expand their ranges towards the pole in response to warming waters and sea ice free conditions by the end of the 21st century. These poleward shifts could alter the structure, composition and functions of future Arctic communities, which are currently dominated by smaller and short-lived species. The future species pool in the Arctic waters will also have more similar functions within the ecosystem, impacting regional food webs. It is also likely that there will be considerable socioeconomic impacts, as commercially important species shift northwards, which could increase operational fishing costs.

"These projected impacts are expected to raise challenges for ocean governance, conservation and resource management of shifting fisheries," says Alabia. "Our results provided glimpses of potential futures of the Arctic marine ecosystems, nonetheless, and some of these ecological shifts are already being documented. As such this highlights the need for continued monitoring and improving climate-ready strategies to buffer climate change impacts and maintain the integrity and functioning of vulnerable ecosystems."

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Materials provided by Hokkaido University. Note: Content may be edited for style and length.

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September 30, 2020 at 12:51AM
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Researchers use membranes that remove salt from water to help 'split' sea water into fuel - Phys.org

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Generating renewable hydrogen fuel from the sea
Here is a visual representation of how ion movement is affected by a reverse osmosis (RO) membrane versus a cation-exchange membrane. Chloride ions from the seawater are not able to pass through the RO membrane and oxidize into chlorine gas. Credit: Logan Research Group

The power of the sun, wind and sea may soon combine to produce clean-burning hydrogen fuel, according to a team of Penn State researchers. The team integrated water purification technology into a new proof-of-concept design for a sea water electrolyzer, which uses an electric current to split apart the hydrogen and oxygen in water molecules.

This new method for "sea water splitting" could make it easier to turn wind and into a storable and portable fuel, according to Bruce Logan, Kappe Professor of Environmental Engineering and Evan Pugh University Professor.

"Hydrogen is a great fuel, but you have to make it," Logan said. "The only sustainable way to do that is to use renewable energy and produce it from water. You also need to use water that people do not want to use for other things, and that would be sea water. So, the holy grail of producing hydrogen would be to combine the sea water and the wind and solar energy found in coastal and offshore environments."

Despite the abundance of sea water, it is not commonly used for water splitting. Unless the water is desalinated prior to entering the electrolyzer—an expensive extra step—the chloride ions in sea water turn into toxic chlorine gas, which degrades the equipment and seeps into the environment.

To prevent this, the researchers inserted a thin, semipermeable membrane, originally developed for purifying water in the reverse osmosis (RO) treatment process. The RO membrane replaced the ion-exchange membrane commonly used in electrolyzers.

"The idea behind RO is that you put a really on the water and push it through the membrane and keep the chloride ions behind," Logan said.

In an electrolyzer, sea water would no longer be pushed through the RO membrane, but contained by it. A membrane is used to help separate the reactions that occur near two submerged electrodes—a positively charged anode and a negatively charged cathode—connected by an external power source. When the power is turned on, start splitting at the anode, releasing tiny hydrogen ions called protons and creating oxygen gas. The protons then pass through the membrane and combine with electrons at the cathode to form hydrogen gas.

With the RO membrane inserted, seawater is kept on the cathode side, and the chloride ions are too big to pass through the membrane and reach the anode, averting the production of chlorine gas.

But in water splitting, Logan noted, other salts are intentionally dissolved in the water to help made it conductive. The ion-exchange membrane, which filters ions by , allows salt ions to pass through. The RO membrane does not.

Researchers use membranes that remove salt from water to help 'split' sea water into fuel
Sea water can be converted into hydrogen fuel using this design for a sea water electrolyzer, according to Penn State researchers. Credit: Tyler Henderson

"RO membranes inhibit salt motion, but the only way you generate current in a circuit is because charged ions in the water move between two electrodes," Logan said.

With the movement from the bigger ions restricted by the RO membrane, the researchers needed to see if there were enough tiny protons moving through the pores to keep a high electrical current.

"Basically, we had to show that what looked like a dirt road could be an interstate," Logan said. "We had to prove that we could get a high amount of current through two electrodes when there was a membrane between them that would not allow salt ions to move back and forth."

Through a series of experiments recently published in Energy & Environmental Science, the researchers tested two commercially available RO membranes and two cation-exchange membranes, a type of ion-exchange membrane that allows the movement of all positively charged ions in the system.

Each were tested for membrane resistance to ion movement, the amount of energy needed to complete reactions, hydrogen and oxygen gas production, interaction with and membrane deterioration.

Logan explained that while one RO turned out to be a "dirt road," the other performed well in comparison to the cation-exchange membranes. The researchers are still investigating why there was such a difference between the two RO membranes.

"The idea can work," he said. "We do not know exactly why these two membranes have been functioning so differently, but that is something we are going to figure out."

Recently, the researchers received a $300,000 grant from the National Science Foundation (NSF) to continue investigating sea water electrolysis. Logan hopes their research will play a critical role in reducing carbon dioxide emissions around the world.

"The world is looking for renewable hydrogen," he said. "For example, Saudi Arabia has planned to build a $5 billion facility that is going to use sea water. Right now, they have to desalinate the . Maybe they can use this method instead."


Explore further

Water splitting advance holds promise for affordable renewable energy

More information: Le Shi et al, Using reverse osmosis membranes to control ion transport during water electrolysis, Energy & Environmental Science (2020). DOI: 10.1039/D0EE02173C

Citation: Researchers use membranes that remove salt from water to help 'split' sea water into fuel (2020, September 29) retrieved 29 September 2020 from https://ift.tt/2ENHwBo

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September 30, 2020 at 04:01AM
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Guided-missile destroyer breaks record for longest time spent at sea - NavyTimes.com

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The guided-missile destroyer Stout reached a record 208 days at sea Sept. 26 as part of a deployment to the U.S. 5th Fleet area of operations, near the Middle East and North Africa.

Their deployment surpassed the previous record of 207 days, set earlier this year by aircraft carrier Dwight D. Eisenhower and guided-missile cruiser San Jacinto, according to a Navy news release.

In efforts to mitigate the risk of sailors contracting COVID-19, fewer port visits and more time training at sea have become the norm.

Earlier this year, the aircraft carrier Theodore Roosevelt experienced an outbreak of COVID-19, the handling of which led to the firing of its commanding officer. Now, the TR is planning to deploy again in upcoming months.

When the rest of Destroyer Squadron 26 returned home this summer, the Stout remained to support Task Force 50, Task Force 51/5, and Coalition Task Force Sentinel, the arm of the International Maritime Security Construct responsible for operations, the Navy reported.

The Stout provided overwatch for more than 550 vessels in 139 days of supporting Task Force Sentinel, ensuring open trade was not interfered with.

“USS Stout has been instrumental in maintaining freedom of navigation in the region. Its regular presence has helped to deter potential threats and provide reassurance to the global merchant community,” said Cmdr. Rob Bellfield, commander of CTF Sentinel, in the Navy news release. “I wish to thank the crew for their efforts and wish them all the best during the rest of their deployment.”

Alongside TF 51/5 the ship also practiced island amphibious assault and joint air and surface integration. In support of both the Ike and Nimitz Carrier Strike Groups, the Stout patrolled the Strait of Hormuz and escorted Army logistics support vessels.

While at sea, the crew also achieved another first for the Navy, conducting the first-ever mid-deployment voyage repair at sea. Mid-deployment voyage repairs require significant repair and maintenance to keep the ship running for the remainder of the deployment.

“We are extremely proud of Stout’s accomplishments in theater as they’ve been operating to ensure freedom of navigation,” said NAVCENT boss Vice Adm. Samuel Paparo in a news release. “Under the challenges of COVID-19 and the uncertainty of regional tensions, Stout embodied their motto and prevailed with ‘Courage, Valor and Integrity.’”

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September 30, 2020 at 05:03AM
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Beluga whales take first swim in new open-water sea sanctuary - Statesville Record & Landmark

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A pair of previously captive beluga whales have taken their first swim in their new open-water sea sanctuary off Iceland's south coast. The whales — called Little White and Little Grey — were captured in Russian waters and sold to Changfeng Ocean World aquarium in Shanghai over ten years ago. Their new home is a 32,000-square-metre sea pen in a pristine bay called Klettsvik, accessible by whale-watching boats. 

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For Hong Kong Protesters Caught at Sea, Trial in China Is Likely - The New York Times

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HONG KONG — The 12 protesters who were caught fleeing Hong Kong in a speedboat last month have not been allowed to call their families. They have been denied bail and held without charge in a Chinese detention center. They have been barred from meeting rights lawyers appointed by their relatives.

Soon, they will face criminal charges related to their escape, and they are expected to do so in the mainland’s murky justice system.

In Hong Kong, they have become a potent reminder of the very same deep-seated anxiety that last year triggered large demonstrations and evolved into the most serious challenge to the Communist Party’s rule in decades. The protests targeted a proposed extradition law, since abandoned, that would have exposed the city’s residents to trial on the mainland, where courts are controlled by the party.

“This is what we had been fearing when we protested against the extradition bill, that people from Hong Kong could get sent over to China into a totally different system that’s well known for not following their own laws,” said Beatrice Li, the sister of Andy Li, an activist who was one of the people on the boat.

Anxiety about Beijing’s tightening grip over Hong Kong has only intensified since the Communist Party imposed a sweeping national security law on the territory in June, to punish vaguely defined political crimes such as subversion. Mr. Li had been arrested in August under the new law, and released on bail.

As many as 200 Hong Kong protesters are believed to have fled to Taiwan, where the activists are believed to have been headed, over the past year. Going there by sea has become increasingly risky, and smugglers who once plied the route are now unwilling to participate, so some members of the group — 11 men and one woman — had learned to pilot a boat themselves, according to two people who had heard details of their attempted escape but were not directly involved.

Another protester, Liu Tsz-man, a 17-year-old who was arrested by the police in Hong Kong over an arson conspiracy charge last year, never told his family that he planned to flee. But looking back, there were signs.

A few days before he went missing, Mr. Liu had been an unusually good son, according to his brother. The teenager had gone out early in the morning to wait in line for a table at a breakfast dim sum place, a task that usually fell to their father. He also went out of his way to buy cigarettes for his dad. Then, suddenly, he was nowhere to be found.

Image
Credit...Lam Yik Fei for The New York Times

The group set off early on Aug. 23 from Po Toi O, a fishing village in a rural part of the territory’s northeast, the Hong Kong government said in a statement Saturday, describing information conveyed by the mainland police. The Chinese Coast Guard stopped the boat around 9 a.m., about 45 miles southeast of Hong Kong Island.

“When the news reported it, they didn’t have names, only that people had been arrested,” Mr. Liu’s 23-year-old brother, Jason Liu, said in an interview. “Then the police showed up at our door.”

The 12 are now being held in a detention center that is a 15-minute walk from the mainland’s border with Hong Kong, in Yantian, a district of the Chinese city of Shenzhen.

They are expected to be formally arrested by prosecutors in Shenzhen in the coming days on charges of crossing the boundary illegally, according to the Hong Kong government. The immigration offense carries a maximum penalty of up to one year in prison, or seven years if they are found to have organized such an effort. An official at China’s foreign ministry has described the detainees as separatists — making clear the political lens by which the authorities are viewing the case.

Credit...Kin Cheung/Associated Press

It is not uncommon for detainees on the mainland to be held for long periods without bail or access to lawyers and relatives, particularly in politically sensitive cases. In Hong Kong, the police may not keep a person in custody for more than 48 hours without charge, in general, and detainees have the right to choose their lawyers.

Liang Xiaojun, a human rights lawyer in China hired by relatives of Mr. Li to represent him, said he and three other lawyers chosen by the detainees’ families were told by the police at the Yantian detention center that their clients had already chosen their attorneys. The police in China sometimes compel defendants to accept state-selected lawyers in order to prevent rights lawyers from putting up a robust defense in court.

“I’m disappointed with the current situation,” Mr. Liang said in an interview.

Mr. Li, 30, a computer programmer who likes to play video games and read Japanese graphic novels, joined the protest movement last year. He volunteered with the group Fight For Freedom, Stand With Hong Kong, which organized international campaigns to support the movement. He became more prominent when he helped organize a group of overseas poll monitors for local Hong Kong elections in November.

Mr. Li was arrested last month on suspicion of being “in collusion with a foreign country or with external elements” under the national security law. He also faces possible charges of possessing illegal ammunition, apparently related to his collecting of spent tear gas cartridges, rubber bullets and other materials used by the police.

Pro-democracy lawmakers and activists have pressured Hong Kong officials to push the Chinese government for the detainees’ return. Some activists have tried to organize protests in support of the 12 on Thursday, China’s National Day holiday.

On Tuesday, Beijing’s liaison office in Hong Kong said that demands for their release were “absurd,” calling the detainees’ supporters “black hands behind the calamities of Hong Kong.”

Credit...Lam Yik Fei for The New York Times

The Hong Kong authorities have emphasized that most of the 12 detainees had been facing serious charges related to explosives, arson, rioting, assaulting police and weapons possession. The city’s leader, Carrie Lam, said last week that the group must first face justice on the mainland before the Hong Kong government assists in their repatriation.

But their relatives are concerned about abuses they might face on the mainland, where forced confessions and other violations are common.

“There are so many stories of torture,” said Ms. Li, Andy Li’s sister, citing cases of people from Hong Kong who had been held in China, including Simon Cheng, a former British consulate employee who said Chinese security agents had hung him in a spread-eagled pose and deprived him of sleep. “All of their accounts about what happened inside during their detentions, it is basically my fear right now.”

The secrecy surrounding the detentions adds to concerns that the broader clampdown on the pro-democracy movement this year will fundamentally change the city’s freewheeling political culture.

Weeks after the security law was imposed, the authorities postponed legislative elections by one year, citing concerns about the coronavirus pandemic. But opposition lawmakers accused the government of trying to avoid a rout of establishment candidates as in last November’s elections, and they briefly debated resigning in protest. This week, at least 15 of them said they would stay in the legislature, while three others decided to leave.

The erosion of Hong Kong’s autonomy has become a major point of contention in the downward spiral of relations between China and the United States. Secretary of State Mike Pompeo has expressed concern about the detention of the protesters on the boat and called on the authorities to ensure due process for the group, whom he called “Hong Kong democracy activists.”

Hua Chunying, a spokeswoman for China’s Ministry of Foreign Affairs, responded with a tweet saying that the 12 were “not democratic activists, but elements attempting to separate” Hong Kong from China.

Credit...Lam Yik Fei for The New York Times

Her statement angered many of the family members, who responded that their relatives were not separatists, and that they deserved a fair trial regardless of their political beliefs.

“As long as your voice is different from that of the government, they’ll say we’re pro-independence,” said Yin Chan, the mother of Li Tsz-yin, a 30-year-old surveyor who was on the boat. “We’re not asking for independence. We want a fair, just society.”

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Marine biodiversity reshuffles under warmer and sea ice-free Pacific Arctic - Phys.org

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Marine biodiversity reshuffles under warmer and sea ice-free Pacific Arctic
Geographic map of the Pacific Arctic region, highlighting the study area in purple contour. Credit: Irene D. Alabia, et al., Science of The Total Environment, supplementary file, July 15, 2020

Climate warming will alter marine community compositions as species are expected to shift poleward, significantly impacting the Arctic marine ecosystem.

The biodiversity of marine communities in the Pacific Arctic under future climate change scenarios highlights profound changes relative to their present patterns. Alterations in marine distributions in response to warming and sea ice reduction are likely to increase the susceptibility and vulnerability of Arctic ecosystems. The findings, published by Hokkaido University researchers in the journal Science of the Total Environment, also suggest that there will be potential impacts on the ecosystem function and services.

Fisheries oceanographer Irene Alabia of Hokkaido University's Arctic Research Center along with colleagues in Japan and the US investigated how future climate changes will impact the marine biodiversity in the Bering and Chukchi Seas. These seas extend from Alaska to Russia in the northern Pacific and southern Arctic oceans.

"This area forms a 'biogeographical transition zone': a biodiversity-rich region covering two distinct areas with specific features that encourage the coexistence of species living at or close to their distribution limits," explains Alabia. "These zones are vulnerable to , and climatic disruptions can create favorable conditions for the shift of warm-water species into previously colder-water zones."

Marine biodiversity reshuffles under warmer and sea ice-free Pacific Arctic
Spatial distribution of functional traits of marine communities in the Eastern Bering and Chukchi Seas for the present-day (left panels) and late-century periods under low (middle panels) and high (right panels). Larger, longer-lived (top row) and more predatory (bottom row) fish and invertebrates will expand northwards as the seas warm; how far their ranges expand is determined by the extent of warming. Credit: Irene D. Alabia, et al., Science of The Total Environment, July 15, 2020

Scientists are interested in understanding how species in biogeographical transition zones are responding to climate changes and other . This information could help in conservation planning, , and in studying the role of evolutionary history in shaping currently existing communities.

Alabia and her team mapped the present and future spatial distributions of 26 fish and in the Bering and Chukchi Seas. Using species records, , and sea ice concentration data, the authors developed species distribution models to predict the distributional ranges under the present-day (1993-2017) and future (2026-2100) climate conditions. From the model outputs, the changes in species richness and compositional diversity in terms of species' phylogeny and functional traits between time periods and across contrasting levels of warming were elucidated.

The findings suggest that larger, longer-lived and more predatory fish and invertebrates will expand their ranges towards the pole in response to warming waters and sea ice free conditions by the end of the 21st century. These poleward shifts could alter the structure, composition and functions of future Arctic communities, which are currently dominated by smaller and short-lived species. The future species pool in the Arctic waters will also have more similar functions within the ecosystem, impacting regional food webs. It is also likely that there will be considerable socioeconomic impacts, as commercially important species shift northwards, which could increase operational fishing costs.

"These projected impacts are expected to raise challenges for ocean governance, conservation and resource management of shifting fisheries," says Alabia. "Our results provided glimpses of potential futures of the Arctic marine ecosystems, nonetheless, and some of these ecological shifts are already being documented. As such this highlights the need for continued monitoring and improving climate-ready strategies to buffer change impacts and maintain the integrity and functioning of vulnerable ecosystems."


Explore further

Mapping species range shifts under recent climatic changes

More information: Irene D. Alabia et al. Multiple facets of marine biodiversity in the Pacific Arctic under future climate, Science of The Total Environment (2020). DOI: 10.1016/j.scitotenv.2020.140913

Citation: Marine biodiversity reshuffles under warmer and sea ice-free Pacific Arctic (2020, September 29) retrieved 29 September 2020 from https://ift.tt/2EHr5Gz

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

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September 29, 2020 at 09:04PM
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Senin, 28 September 2020

Ancient Adélie penguin colony revealed by snowmelt at Cape Irizar, Ross Sea, Antarctica - Science Daily

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Researcher Steven Emslie encountered a puzzle at Cape Irizar, a rocky cape located just south of the Drygalski Ice Tongue on the Scott Coast, Ross Sea. He found both ancient and what appeared to be fresh remains of Adelie penguins, mostly of chicks, which frequently die and accumulate at these colonies. However, the "fresh" remains were puzzling, he says, because there are no records of an active penguin colony at this site since the first explorers (Robert Falcon Scott) in 1901-1903 came to the Ross Sea.

Emslie found abundant penguin chick bones scattered on the surface, along with guano stains, implying recent use of the site, but that wasn't possible, says Emslie. Some of the bones were complete chick carcasses with feathers, now falling apart from decay as at a modern colony, as well as intact mummies. Emslie and his colleagues collected some of these surface remains for further analysis and radiocarbon dating to try and figure out what was going on there.

The team found old pebble mounds scattered about the cape. These mounds are former nesting sites of Adélie penguins because they use pebbles to build their nests. When they abandon a site, the pebbles become scattered and stand out on the landscape, since they are all about the same size.

"We excavated into three of these mounds, using methods similar to archaeologists, to recover preserved tissues of penguin bone, feather, and eggshell, as well as hard parts of prey from the guano (fish bones, otoliths). The soil was very dry and dusty, just as I've found at other very old sites I've worked on in the Ross Sea, and also had abundant penguin remains in them. Overall, our sampling recovered a mixture of old and what appeared to be recent penguin remains implying multiple periods of occupation and abandonment of this cape over thousands of years. In all the years I have been doing this research in Antarctica, I've never seen a site quite like this."

The analyses reported in Emslie's recent paper published in Geology indicate at least three occupation periods of the cape by breeding penguins, with the last one ending at about 800 years ago. When that occupation ended, either due to increasing snow cover over the cape or other factors (the Little Ice Age was beginning about then too), the "fresh" remains on the surface were covered in snow and ice and preserved intact until recent exposure from snowmelt.

Global warming has increased the annual temperature in the Ross Sea by 1.5-2.0 °C since the 1980s, and satellite imagery over the past decade shows the cape gradually emerging from under the snow. Thus, says Emslie, "This recent snowmelt revealing long-preserved remains that were frozen and buried until now is the best explanation for the jumble of penguin remains of different ages that we found there."

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Materials provided by Geological Society of America. Note: Content may be edited for style and length.

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September 29, 2020 at 08:03AM
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Company to harvest sea oats in Emerald Isle for new dunes - Carolinacoastonline

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EMERALD ISLE — If you see people messing with sea oats in the dunes along the Emerald Isle strand in early October, don’t be alarmed, they’re doing authorized work for next year’s beach nourishment project.

Greg Rudolph, manager of the Carteret County Shore Protection Office, said Monday crews from Earthbalance, a Florida company, will harvest not only sea oat seeds but also bitter panicum and beach elder cuttings. The cuttings will be used to grow new plants that will be installed on dunes to be created in the 2021 nourishment project in extreme western, central and extreme eastern Emerald Isle.

The plants will help hold those new dunes in place, which is the reason it’s illegal and punishable by a fine to remove sea oats from beaches in North Carolina and other coastal states.

“There will be no four-wheel drive vehicles, just a field crew that will strip the spikelets, or seed heads, by hand,” Mr. Rudolph said Monday. “The stem stalks and the plants will be left behind without any damage.

“The spikelets will then be processed to yield the seeds, and the seeds will be used to generate the plantings for the (2021) project.”

It takes quite a while to grow sea oats suitable for seed harvest for plants used in stabilizing dunes, Mr. Rudolph added.

Company to harvest sea oats in Emerald Isle for new dunes

A Florida company early next month will harvest seeds from sea oats, right, and stalks from bitter panicum, left, for use in dune vegetation planting next year in Emerald Isle. Carteret County Shore Protection Office photo)

 

“It’s takes about a year and a half, more or less, for new sea oat plantings to send up the stem with spikelets,” he said. “For instance, the plants we planted in the 2019 (nourishment project) shot up stalks this year, and the plants we planted in 2020 are still too young.”

There are plenty of mature sea oats in portions of Emerald Isle that have not experienced beach nourishment recently, so there are enough available to harvest seeds and start growing plants that will be put in next year.

The county’s contract for the 2021 nourishment project stipulates that only native vegetation can be used for the dune planting, which takes place after nourishment work is complete. This year’s planting effort took several months.

The county opened bids for the 2021 project, known as Phase III of the post-Hurricane Florence beach nourishment project, earlier this year and awarded the contract to the low bidder, Great Lakes Dredge and Dock Co., of Illinois, for $31,611,770. It calls for placement of about 2 million cubic yards of sand in Emerald Isle.

Earthbalance is a subcontractor working for Great Lakes.

The nourishment work will start early next year and must be finished April 30, 2021 because of federal law that protects sea turtles, which hit the beaches in late spring and early summer to put in nests that contain eggs that hatch in the fall.

 

Contact Brad Rich at 252-864-1532; email Brad@thenewstimes.com; or follow on Twitter @brichccnt.

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September 29, 2020 at 11:00AM
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Company to harvest sea oats in Emerald Isle for new dunes - Carolinacoastonline

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