19 Jul 2013:
European Fish Stocks
Show Signs of Recovery, Study Says
A major assessment of fish stocks in the northeast Atlantic Ocean shows that many species are recovering and are now being fished sustainably.
The surprising findings, reported in the journal Current Biology,
are based on data from government research institutes that collected millions of measurements of fish, both at sea and in markets. The study showed that for the first time in decades the majority of fish stocks in the northeast Atlantic are recovering, thanks to reforms instituted by individual nations and the European Union in 2002. This good news comes amid widespread criticism of EU fisheries policies
, which recently have undergone further reform. “We should be aware that low fishing pressure needs to be maintained until stocks recover,” said researcher Robin Cook of the University of Strathclyde in Scotland. “This is only the first step. Now we need to see numbers increase as a result of continued low fishing pressure.”
16 Jul 2013:
Russia Blocks Plans to Create
Massive Marine Reserve in Antarctica
Russian officials have blocked plans to establish the world’s largest marine reserve
in the waters off Antarctica, citing concerns that it would restrict their
John B. Weller/The Pew Charitable Trusts
Ross Sea pack ice
fishing interests in the region, according to news reports. The plan, which was proposed by the U.S. and New Zealand, would have protected a total of 2.3 million square miles in the Ross Sea, a deep, high-latitude body of water in the Southern Ocean. But during a meeting of the 25-member Commission for Conservation of Antarctic Marine Living Resources, Russia questioned whether the organization had the legal right to create such a haven. A key sticking point for the Russians was the potential loss of the fishery for krill, a shrimp-like creature that is a critical food source for penguins, seabirds, seals, and whales, but is netted for use in Omega-3 dietary supplements.
10 Jul 2013:
Massive Iceberg Calves
Off Antarctica’s Pine Island Glacier
A massive chunk of Antarctica’s fastest-moving ice stream, the Pine Island Glacier, dropped into the Amundsen Sea this week
, nearly two years after
Click to enlarge
Alfred Wegener Institute/German Space Agency
Pine Island Glacier, 2011-2013
scientists first observed a crack in the glacier tongue. German scientists, who have been tracking the progress of the ice mass since NASA satellites first observed the crack in 2011, say the calved iceberg measured 720 square kilometers (278 square miles). There is no conclusive proof that climate change triggered the ice break, said Angelika Humbert, an ice researcher at the Alfred Wegener Institute. But shifting wind patterns around Antarctica are bringing warmer waters to the surface of the Southern Ocean in West Antarctica, which is hastening the thinning of some glaciers. Humbert said those warmer waters are causing the Pine Island Glacier to flow more rapidly into the Amundsen Sea.
08 Jul 2013:
Crowdsourcing Project Targets
Open-Source Tool for Ocean Research
A team of marine researchers is developing a blueprint for an inexpensive tool to collect oceanographic data, a venture they hope will make ocean science more accessible
to other scientists, educators, and marine enthusiasts. Using an open-access model
, the researchers hope to build their own CTD, a widely used oceanographic instrument that collects information on ocean temperature, depth, salinity, and density. While CTDs are vital to marine research, the technology can be prohibitively expensive for some “citizen scientists,” with costs running $5,000 to $25,000 per instrument. Traditional CTDs are small, cylindrical instruments that are dropped from boats and relay data back to shipboard computers. Using a crowdsourcing website, organizers of the so-called OpenCTD project are raising funds to design a CTD capable of collecting ocean data down to 200 meters at a cost of about $200.
01 Jul 2013:
Climate Change Driving
More Active El Niño Cycles, Study Says
A new analysis of tree-ring data indicates that the climate cycle known as the El Niño – Southern Oscillation (ENSO) has been more active during the latter part of the 20th century than at any other time during the past seven centuries
, suggesting that global warming is affecting this climate phenomenon. Using data from 2,222 tree-ring chronologies from the tropics and mid-latitudes in both the northern and southern Hemispheres, a team of scientists determined that ENSO-related behavior in the late 20th century was far greater than the natural variability reflected in data going back to 1300. A naturally occurring climate cycle, ENSO is characterized by warmer ocean temperatures off the west coast of South America, a phenomenon that can cause major droughts, floods, and extreme weather across the Pacific. According to Jinbao Li, a scientist at the University of Hawaii and lead author of the study published in the journal Nature Climate Change
, greenhouse gases are altering the planet’s radiation balance and thus intensifying ENSO cycles.
20 Jun 2013:
Global Reports Underline
Threats to Planet’s Bird Species
New global research underlines the rising threats facing the world’s bird species, with three reports providing evidence that climate change, overfishing, and unsustainable agriculture are taking a heavy toll on
Puffins along the Maine coast.
avian populations worldwide. The U.S. Fish and Wildlife Service (FWS) reports that numbers of some migratory bird populations in Maine — including Arctic terns and puffins — have plummeted in recent years
because their food supplies are disappearing as a result of commercial fishing and the shifting of fish to cooler waters, which is making it more difficult for some birds to feed their young. In a separate study, scientists predict that rising sea levels will devastate habitat for some migratory shore birds
in the coming decades. Higher sea levels, the study predicts, will flood 23 percent to 40 percent of the intertidal habitats for several shorebird species, triggering population declines of as much as 70 percent. Overall, one in eight bird species globally is at risk of extinction
, according to a new report by BirdLife International
17 Jun 2013:
Changes in Jet Stream Triggered
Record Greenland Melt in 2012, Study Says
An unusual shift in the jet stream triggered the historic level of surface ice melt
that occurred across Greenland last summer, a new study says. Using satellite data and a computer model simulation, scientists from the University of Sheffield found that a high-pressure system developed in the mid-troposphere over Greenland for much of the summer, pushing warm southerly winds over the western edge of the ice sheet and creating a “heat dome” over Greenland. According to the study, published in the International Journal of Climatology
, this unprecedented event caused record melting across virtually the entire ice sheet, including on Summit Station, Greenland’s highest peak. Ocean temperatures and Arctic sea ice retreat, meanwhile, played a minimal part in the record surface ice melt, the scientists reported. The study predicted that the record ice melt of 2012 is not likely to be “climatically representative of future ‘average’ summers” during the coming century.
29 May 2013:
Genetically Modified Salmon
Can Breed with Wild Fish and Thrive
Fast-growing, genetically modified salmon can interbreed with wild brown trout and produce offspring that grow rapidly and out-compete other wild salmon in streams
, according to a new study. Researchers from Memorial University in Newfoundland, Canada, found that so-called “Frankenfish” — which are close to being approved for sale in the United States
— can easily interbreed with brown trout in the wild, creating offspring that aggressively compete for food with salmon. In settings that simulated real streams, the offspring of the genetically modified (GM) salmon and brown trout were so aggressive that they suppressed the growth of GM salmon by 82 percent and wild salmon by 54 percent. “These findings suggest that complex competitive interactions associated with transgenesis and hybridization could have substantial ecological consequences for wild Atlantic salmon should they ever come into contact [with GM salmon] in nature,” the researchers wrote in the Proceedings of the Royal Society B
. The creator of the GM salmon, Aqua Bounty, said the risks were minimal since all the GM salmon will be female, sterile, and produced in tanks on land.
22 May 2013:
Whale’s Battle with Nets
Is Revealed Through Monitoring Device
A small monitoring tag attached to an entangled North Atlantic right whale revealed just how much fishing gear impairs a whale’s ability to swim, dive, and feed
, scientists say. After locating a two-year-old whale,
EcoHealth Alliance, under permit number 594-1759
The entangled whale
dubbed Eg 3911, with fishing gear entangled around her mouth and pectoral fins, a team of scientists was able to attach a so-called Dtag in January 2011 that recorded her movements before, during, and after the team removed the nets. The whale “altered its behavior immediately following the disentanglement,” according to the study published in the journal Marine Mammal Science
. She swam faster, dove twice as deep, and stayed underwater for longer periods. Scientists say the added buoyancy, increased drag and reduced speed caused by such gear may overwhelm an animal's ability to forage for preferred prey, delay its arrival to feeding or breeding grounds, and ultimately drain its energy. Indeed, two weeks after disentangling Eg 3911 from the nets, an aerial survey spotted her dead at sea.
14 May 2013:
Shifting Petrel Diets Suggest
Effect of Humans on Ocean Food Web
An analysis of the bones of ancient and modern Hawaiian petrels has revealed that modern petrels, which forage in the open ocean, are eating prey lower on the food chain
than in centuries past, a dramatic shift
that coincides with the rise of industrial fishing. In tests conducted on petrel bones collected over three decades in the Hawaiian islands, a team of scientists found that the bones from 4,000 to 100 years ago contained higher ratios of nitrogen-15 and nitrogen-14 isotopes than the more recent bones, suggesting that the earlier birds ate bigger prey before changes in the food web composition of the Northeast Pacific. According to the scientists, the nitrogen ratio started to decline in the decades after the early 1950s, when industrial fishing started to extend beyond the continental shelves. “Our bone record is alarming because it suggests that open-ocean food webs are changing on a large scale due to human influence,” said Peggy Ostrom, a zoologist at Michigan State University and co-author of the study, published in the Proceedings of the National Academy of Sciences
03 May 2013:
Seawater Energy Technology
Is Focus of Pilot Project in China
The U.S. defense and aerospace giant, Lockheed Martin, is partnering with a major Chinese company to build a pilot project off the southern Chinese coast that will use temperature differentials between the deep and shallow ocean to generate electricity
. The technology, known as ocean thermal energy conversion (OTEC), uses the heat from warm surface waters to boil a fluid with a low boiling point, such as ammonia, producing steam to drive turbines. Colder water is then pumped from 2,500 to 3,000 feet under the sea, which condenses the steam into liquid; the liquid can then be boiled again to produce more steam and power. Lockheed Martin and its Chinese Partner, the Beijing-based Reignwood Group, said their project — the largest OTEC plant ever built — will produce 10 megawatts of power when it opens in 2017, enough to provide electricity for a large, planned resort that Reignwood is building.
29 Apr 2013:
Ocean off the U.S. Northeast
Was Warmest in 150 Years, Report Says
Sea surface temperatures along the northeastern U.S. were warmer in 2012 than during any year in the last 150 years
, a new report finds. According to the National Oceanic and Atmospheric Administration’s (NOAA) latest Ecosystem Advisory for the Northeast Shelf
, sea surface temperatures across the region — which extends from Cape Hatteras, N.C., to the Gulf of Maine — averaged 14 degrees C (57.2 degrees F) last year, significantly higher than the average temperature over the last three decades, which was 12.4 degrees C (54.3 degrees F). It was also the biggest one-year increase since records were first kept in 1854. While the data historically has been collected by ship-board instruments, NOAA now also incorporates satellite remote-sensing technology. “Changes in ocean temperatures and the timing and strength of spring and fall plankton blooms could affect the biological clocks of many marine species, which spawn at specific times of the year based on environmental cues like water temperature,” said Kevin Friedland, a NOAA scientist.
16 Apr 2013:
U.S. Offshore Seismic Testing
Threatens Many Marine Species, Study Says
The proposed use of seismic air guns in the search for offshore oil and gas reserves along the U.S. East Coast could injure or kill nearly 140,000 marine animals
annually and disrupt the vital activities of other species,
Moira Brown/New England Aquarium
North Atlantic right whale
a new study says. The seismic testing, in which guns filled with compressed air are fired repeatedly over deep-sea target areas to provide energy companies an image of the deposits below, would threaten marine species of all sizes, from tiny fish eggs to large whales, according to an analysis by the conservation group Oceana
. The group said that the powerful air gun blasts, which it describes as “100,000 times more intense than a jet engine,” could disturb the breathing, feeding, and mating habits for dolphins and whales and cause injury or death to endangered species such as the North Atlantic right whale. The analysis comes as the U.S. Interior Department’s Bureau of Ocean Energy Management completes a study of the potential impacts of seismic activities from Delaware to Florida. Oil industry officials point to other research that shows seismic testing is unlikely to threaten marine mammals.
12 Apr 2013:
Many Marine Mammal Species
Have Rebounded Since U.S. Protections
Forty years after the passage of the Marine Mammal Protection Act (MMPA), no marine mammal species in U.S. waters has been extirpated and the populations of
many marine animals are more abundant
than in 1972,
a new study says. While many species, including the endangered right whale, remain at significant risk, the populations of other species — including gray seals in New England and sea lions and elephant seals on the Pacific coast — have “recovered to or near their carrying capacity,” scientists say. “At a very fundamental level, the MMPA has accomplished what its framers set out to do, to protect individual marine mammals from harm as a result of human activities,” said Andrew Read, a professor at Duke University and co-author of the study, published in the Annals of the New York Academy of Sciences
. Passed at a time when numerous species were on the edge of extinction, the MMPA imposed strict regulations against commercial killing and the incidental bycatch of marine mammals by the fishing industry.
11 Apr 2013:
Marine Council's ‘Eco-Labeling’
Process Is Too Lenient, Report Says
The process by which the Marine Stewardship Council (MSC) certifies seafood as sustainable is too lenient and discretionary
, allowing for “overly generous interpretations” from third-party certifiers and adjudicators, a new report says. Launched in 1997, the UK-based MSC administers a well known eco-labeling process to inform consumers which fisheries are sustainable and provide incentives for better fisheries management. But in an analysis of 19 formal complaints against the council, a group of researchers found that several of the fisheries that received the MSC’s “sustainable” label — accounting for 35 percent of labeled seafood — apparently do not meet the council’s standards. For example, they found that Canada’s longline fishery for swordfish resulted in an extraordinary amount of incidental bycatch of other species, with the annual catch of 20,000 swordfish also netting 100,000 sharks, 1,200 endangered loggerhead turtles, and 170 leatherback turtles, according to the report, published in the journal Biological Conservation
Interview: A Marine Biologist
Works to Create a ‘Wired Ocean’
Even as populations of sharks, bluefin tuna, and other large fish are being severely over-exploited, scientists still know surprisingly little about when and where the ocean’s biggest predators congregate to feed and spawn,
making it difficult to protect biological hotspots. Stanford University marine biologist Barbara Block is seeking to narrow that knowledge gap by deploying an armada of satellite tags on the backs of ocean creatures. Block envisions a wired ocean, a blue fount of data in which tags, smart buoys, and mobile robots reveal the secrets of marine life. In an interview with Yale Environment 360
, Block discusses the wealth of data gathered by the latest electronic tags and explains why it’s important to put the fruits of this research into the public’s hands “What we need is environmental interest and awareness that connects humans to the world,” says Block, "or else we're going to end up with the same problem we had on the continents, where the large mammals are gone."
Read the interview
08 Mar 2013:
Largest U.S. Dam Removal
Releases Huge Amount of Sediment
Scientists tracking the aftermath of the largest dam removal in U.S. history say the dismantling of a dam in northwestern Washington state has unleashed about 34 million cubic yards of sediment and debris
that built up
A plume of sediment at the mouth of the Elwha River.
for more than a century. While about one-third of the 210-foot Glines Canyon Dam on the Elwha River still stands, vast amounts of sediment are already flowing downstream, allowing University of Washington (UW) scientists a rare opportunity to track the discharges and study their ecological impacts. Scientists say it is unclear where much of the sediment will end up — or what the environmental consequences will be. In an ongoing study, they will use sophisticated technology to track particles in the water and monitor their accumulation on the ocean floor. Scientists say the sediment — enough to fill 3 million truckloads — could create murkier water conditions, threatening the reproduction of salmon and blocking light for marine life.
08 Feb 2013:
Memory of Magnetic Landscape
Guides Salmon to Home Rivers, Study Shows
Although magnetism has been known to play a role in the remarkable homing ability of salmon, a new study clarifies just how the fish use magnetic fields
to travel thousands of miles to their natal rivers to spawn. Researchers at Oregon State University solved this mystery by studying 56 years of fishery data involving the millions of sockeye salmon that annually pour into British Columbia’s Fraser River. Vancouver Island sits in front of the Fraser, and the routes the salmon took around the island in different years offered clues to how the fish decipher shifting magnetic fields. When the magnetic field of the northern passageway around Vancouver Island was similar to that experienced by the fish when they left the river two years earlier, the returning salmon tended to chose the northern route;
the reverse was true when there was a more southerly magnectic field. Lead researcher Nathan Putnam said this showed that juvenile salmon imprint on the magnetic signature of their home rivers and then seek their way back using that signature. The research was published in Current Biology
05 Feb 2013:
Sea Urchins Offer a Clue
To New Way to Capture Carbon Dioxide
British researchers have discovered that sea urchins use nickel particles on their exoskeletons to effectively capture CO2 and turn it into a solid form, an intriguing finding that could offer an inexpensive way to capture and store carbon
from fossil fuel-fired power plants. Scientists from Newcastle University were studying how marine organisms absorb CO2 to make shells and skeletons when they discovered that sea urchin larvae have a high concentration of nickel on their exoskeletons, which helps them absorb CO2. When the researchers added nickel nanoparticles to CO2-saturated water, they discovered that the nickel completely removed CO2 and turned it into calcium carbonate
, a chalk-like mineral. Current efforts to capture and store carbon dioxide from power plants involve either pumping it underground or using an enzyme called carbonic anhydrase to convert it to calcium carbonate. But both methods are expensive, and the Newcastle researchers say that using nickel to capture and store CO2 bubbled through water could be a thousand times cheaper than employing carbonic anhydrase. “It seems too good to be true, but it works,” said Lidija Siller, a physicist at Newcastle. The research was published in Catalysis Science & Technology.
31 Jan 2013:
Massive UK Wind Turbines
Are a Sign of ‘Super-sizing’ of Wind Power
Two of the world’s largest wind turbines, with blades 60 meters (196 feet) long, have been installed off the Yorkshire coast, a sign of a growing trend toward producing colossal wind turbines to boost generating capacity.
The 6-megawatt turbines, manufactured by Siemens, are so large that they had to be installed using a specially built ship
, Siemens said. The pair of turbines is being erected on an experimental basis to gauge how they perform, but the operator of the offshore wind farm, the Denmark-based DONG energy group, has plans to install dozens more so that production will reach 210 megawatts at the site, located about five miles offshore. DONG says it intends to eventually install 300 of the massive turbines by 2017 at various offshore locations in the U.K., including some in deeper waters. Energy analysts say the 60-meter Siemens turbines reflect growing interest among wind energy companies to deploy ever-larger turbines, with plans in the works to manufacture turbines 100 meters long.
30 Jan 2013:
Satellite Analysis Shows
Gulf Oil Spills Typically Underestimated
An analysis of satellite images has revealed that small oil spills that have become common in the Gulf of Mexico are often much larger than reported
, U.S. scientists say. Using technology that calculates the size of oil slicks based on differences in the texture of water surface, as captured in publicly available satellite photos, a team of oceanographers at Florida State University (FSU) estimated that known human-caused spills in the Gulf were typically about 13 times larger than reported to the U.S. Coast Guard’s National Response Center. The spills are typically the result of minor drilling mishaps or fuel discharges from ships. “There is very consistent underreporting of the magnitude of [oil] releases,” Ian MacDonald, a FSU scientist and team leader, told Nature
. While these relatively minor oil spills may not cause significant environmental damage, the cumulative damage is not known since officials are unaware of the true extent of the spills, said John Amos, president of SkyTruth, a nonprofit organization that participated in the study.
15 Jan 2013:
Key Offshore Transmission Line
To Be Built For U.S. East Coast Wind Power
A group of prominent U.S. investors, including Google, is expected to announce today that it is moving forward with construction on the first leg of an ambitious $5 billion undersea transmission line
that will connect
Atlantic Wind Connection
New Jersey Energy Link
future offshore wind farms along the mid-Atlantic coast, a project they say will avert the regulatory hurdles required in connecting each individual wind farm to land-based electricity lines. The first segment of the project, which will occur in three phases, includes construction of a 189-mile transmission cable along the New Jersey coast. Coordinators of the project, known as the Atlantic Wind Connection, say the cable would deliver more than 3,400 megawatts of electric capacity
from future offshore wind projects to three locations in New Jersey. Construction is expected to begin in 2016, according to the sponsors. The project intends to eventually link offshore wind farms with electricity grids from Virginia to New York.
14 Jan 2013:
Tidal Energy Can Meet 20%
Of UK Electricity Needs, Study Says
UK officials are underestimating the vast energy potential of marine tides
, a renewable and reliable energy source that could meet 20 percent of the nation’s
Kawasaki Heavy Industries
electricity needs, according to a new report. Writing in the journal Philosophical Transactions of the Royal Society A
, researchers explain that while the process of exploiting tidal energy remains expensive, it has the potential to be a more reliable energy source than wind or wave energy and to be more easily managed on electricity grids. While the technology is in the early stages, the researchers say they are optimistic that the two principle means of exploiting tidal energy — construction of barrages across tidal estuaries that generate power from the ebb and flow of the water, and adding underwater turbines in fast-flowing currents — can be implemented in the near future. “From tidal barrages you can reasonably expect you can get 15 percent of UK electricity needs,” Nicholas Yates, a researcher at the National Oceanography Centre and co-author of the report, told BBC News
Interview: What’s Damaging U.S.
Salt Marshes and Why It Matters
For centuries, salt marshes along the U.S. coast have been disappearing, with some experts estimating that 70 percent have been lost to development, rising seas,
and other threats. One factor scientists always thought marshes could withstand was nutrient enrichment, such as the flow of nitrogen and phosphorus from fertilizers and septic systems. But a nine-year study led by Marine Biological Laboratory scientist Linda Deegan shows that an over abundance of nutrients may be contributing to the demise of these salt marshes. In a Yale Environment 360
interview, Deegan describes the study's implications and the vital services that would be lost if marshes disappear, from nourishing marine species to providing a barrier for coastal communities during storms such as Hurricane Sandy. Read the interview
21 Dec 2012:
Changing Oceans May Be Adding
To U.S. Fisheries Decline, Scientists Say
As U.S. fishing regulators weigh stricter catch quotas to allow time for critical species to recover in the waters of New England, scientists say that changing ocean conditions may be a factor in historic fish declines, not just decades of overfishing. Warmer ocean temperatures and changing ecosystems are contributing to declining populations of cod and flounder
in the northeastern U.S., government officials say. In the Gulf of Maine this year, water temperatures were the highest ever recorded, according to the Northeastern Regional Association of Coastal and Ocean Observing Systems. National Oceanic and Atmospheric Administration (NOAA) scientists say that about half of 36 fish stocks — including cod and flounder — have been shifting northward into deeper, cooler waters for four decades. And while some regulators say the only chance of restoring populations is for tougher quotas on bottom-dwelling “groundfish” species, the New England Fishery Management Council this week delayed a vote on such cuts
after fishermen said the reductions would devastate their industry.
06 Dec 2012:
Google Images Document
Devastation of 2011 Tsunami in Japan
As part of an ongoing project to digitally archive the aftermath of the 2011 tsunami in northeastern Japan, Google has published several new panoramic images
that provide a sobering glimpse of the widespread
devastation in communities across the region. The images, taken with the company’s Street View technology in four cities in the Tōhoku region, allows users to take a virtual tour of seriously damaged buildings before they are demolished. One panoramic view of a public housing project illustrates the height of the tsunami wave, which ruined everything up to the fourth floor of the building. Another image, of the condemned Ukedo Elementary School, shows the collapsed auditorium floor beneath the banner of a graduation ceremony that was never held. The images were added to Google’s “Memories for the Future
” website, which is chronicling the affected areas from before and after the tsunami.
30 Nov 2012:
Accelerated Ice Sheet Melt
At Both Poles Documented in Study
The ice sheets of Greenland and Antarctica are losing three to five times as much ice annually
as they did two decades ago, a rate of ice loss equivalent to sea level rise of 0.04 inches per year, according to a new study supported by NASA and the European Space Agency
. In an analysis of data from 10 different satellite missions, the international team of 47 experts calculated that the rate of melt in Greenland is five times greater than during the mid-1990s. While the new findings on total ice loss fall within the range produced by the Intergovernmental Panel on Climate Change in 2007, the new study provides a more definitive assessment that Antarctica’s ice sheets, like Greenland’s, are shrinking. Combined, these ice sheets have added .44 inches (11.1 millimeters) to sea levels worldwide since 1992, accounting for about 20 percent of total sea-level rise during that period. “This will give the wider climate science community greater confidence in ice losses and lead to improved predictions of future sea-level rise,” said Andrew Shepherd, a scientist at the University of Leeds and co-leader of the study, which is published in the journal Science
26 Nov 2012:
Snails in Southern Ocean
Showing Effects of Ocean Acidification
The shells of some sea snails in the Southern Ocean are already dissolving as a result of ocean acidification
, according to a new study. In an analysis of free-swimming pteperods collected from Antarctic waters in 2008, scientists found that the outer layers of the animals’ shells showed signs of unusual corrosion, potential evidence that ocean acidification caused by excess carbon dioxide in the atmosphere may already be disturbing vulnerable marine species. Laboratory tests have shown that acidic water threatens many invertebrate marine species, such as clams and corals, since it hinders their ability to grow shells and exoskeletons. The most vulnerable species are those, like pteropods, that build their shells from aragonite, a form of calcium carbonate that is sensitive to increased acidity, according to the study, published in Nature Geoscience
16 Nov 2012:
Majority of Marine Species
Still Remain Unknown to Scientists
While more new marine species were identified over the last 10 years than during any previous decade, as many as two-thirds of the plant and animal species living in the oceans may still be unknown to scientists, a new study says. Writing in the journal Current Biology
, a team of international scientists estimates that there are
The marbled swimming crab
likely 700,000 to 1 million species in the oceans, of which only 226,000 species have so far been identified
. Another 65,000 are sitting in scientific collections awaiting identification, according to the study. The study, which was produced by 270 experts from 32 countries, represents the most comprehensive inventory of marine life, and notes that the majority of unknown species are composed of crustaceans, mollusks, worms, and sponges. “For the first time, we can provide a very detailed overview of species richness, partitioned among all the marine groups,” said Ward Appeltans, a biologist at UNESCO's International Oceanographic Commission and one of the study’s authors. The complete inventory can be viewed online at www.marinespecies.org
13 Nov 2012:
Gains in Antarctic Sea Ice Cover
Triggered by Wind Shifts, Study Says
Scientists say they have the first direct evidence that changes in Antarctic sea ice drift caused by changing winds have produced an increase in Antarctic sea ice
cover over the last two decades even as historic declines have been observed in the Arctic. Using more than 5 million measurements of daily sea ice movement collected over 19 years, researchers from NASA and the British Antarctic Survey detected long-term changes in sea ice drift
, a phenomenon that has caused overall increases in sea ice cover. While sea ice around Antarctica is constantly being blown away from the continent by northerly winds, the rate of ice movement in some areas has doubled since 1992, causing total sea ice, which reflects heat from the sun, to expand out from Antarctica, according to their findings, which were published in Nature Geoscience
. “The Antarctic sea ice cover interacts with the global climate system very differently than that of the Arctic, and these results highlight the sensitivity of the Antarctic ice coverage to changes in the strength of the winds around the continent,” said Ron Kwok of NASA’s Jet Propulsion Laboratory.