Pollution Could Buy an Extra Decade of Arctic Sea Ice
Air pollution could help preserve ice but that still doesn’t make it good
Credit: NASA
Arctic sea ice continues to dwindle at an exceptional pace. Summer sea ice has declined at a rate of 13 percent per decade, and the rate has sped up in the last 10 years.The main driver for Arctic sea ice’s disappearing act is the rising ocean and air temperatures driven by human greenhouse gas emissions. But that isn’t the only factor affecting Arctic sea ice. Air pollution also plays a role and can actually slow down warming.In the tug of war, aerosols don’t necessarily counter the impacts of climate change on sea ice (or the planet as a whole for that matter). But new research shows that air pollution could buy the planet a decade of ice in the Arctic.“It shows it’s a complex picture,” Nathan Gillett, a research scientist at Environment Canada, said. “Aerosols have quite a substantial impact on Arctic climate.”Gillett co-authored the new research in pre-publication with Geophysical Research Letters. The findings show that aerosols have blunted 60 percent of the warming in the Arctic through the 20th century, a notable statistic given that the Arctic has still warmed at twice the rate as the rest of the planet.This summer saw the fourth-lowest extent on record (and this winter also saw the lowest winter maximum on record). With temperatures projected to keep rising, it’s only a matter of time before the Arctic experiences an ice-free summer.Going forward, aerosols—small particles that make up air pollution and reflect sunlight back into space—could continue to keep the northern reaches of the planet somewhat cool. Using a middle of the road carbon emissions scenario (which is a little optimistic given currently pledges) as well as rising aerosols, Gillett and his team show that the Arctic is likely to see an ice-free summer around 2057.When his team ran the same scenario but capped air pollution at 2000 levels, ice-free summers in the Arctic started more than a decade earlier in 2045.
Read the original post: www.scientificamerican.com
Central Coast Begins to Feel El Niño’s Effects
Hail Storms and Sea Snake Sightings Back Experts’ Warm Winter Predictions
Courtesy Photo - The tropical yellow-bellied sea snake, spotted last week at Silver Strand Beach in Oxnard, is one anomaly suggesting a warm Californian winter.
The National Oceanic and Atmospheric Association (NOAA) released an updated report Thursday on El Niño predictions for the upcoming year. Forecaster Jon Gottschalk of the Climate Prediction Center at the National Weather Service expects average sea-surface temperatures to climb more than 2 degrees Celsius, which would result in warmer weather and higher humidity through January.His report also states that temperature hikes would be the most prominent along the Pacific coast. Within California specifically, forecasters expect above-median rainfall for the central and southern coasts. Though these warm temperatures had already been predicted, Gottschalk’s predictions expect a higher probability of these climate anomalies to actually occur.However, according to NOAA’s deputy director Mike Halpert, there are other factors to consider. “While temperature and precipitation impacts associated with El Niño are favored, El Niño is not the only player. Cold-air outbreaks and snowstorms will likely occur at times this winter. However, the frequency, number, and intensity of these events cannot be predicted on a seasonal timescale,” said Halpert in his report statement.Southern California residents could feel Halpert’s report only a day after its release. On Friday, Santa Barbara County experienced a string of intense thunderstorms that dropped hail the size of dimes in some areas. Multiple flash flood warnings took to the airwaves on Friday and Saturday as well, ranging from Long Beach all the way up to San Luis Obispo, and as far inland as Burbank.Warmer ocean temperatures have not only brought new weather to Southern and Central California, but also new wildlife. PBS (Public Broadcasting Services) has reported that fishermen off the coast of San Diego are discovering Bluefin tuna, yellowtail, and dorado, which are all characteristically found further south in Mexico. Earlier this summer, San Diego and Orange County also saw phenomenal numbers of red crab corpses on their beaches following the species’ movement with the warmer waters.The natural food chain has set up a domino effect, as these migrations of prey have also brought along their predators. According to CBS, a fisherman off the coast of Huntington Beach encountered a ten-foot hammerhead shark while fishing for yellowtail. The same beaches have also been home to sightings of great white sharks — one reportedly bumped a surfer in August.Most recently, two sightings of a venomous sea snake species have been reported. On Thursday evening, Anna Iker reported seeing a yellow-bellied sea snake (Pelamis platura) while at the beach with her kids. Next morning another local resident, Robert Forbes, reported a separate sighting. Heal the Bay, an environmental advocacy nonprofit, confirmed both sightings were at Silver Strand Beach in Oxnard but could not confirm they were of the same animal. The group later stated in a blog post that the last sighting of a yellow-bellied sea snake this far north was in the early 1980s, also during El Niño.
Read the original post: www.independent.com
Ocean Heat Maps Reveal Secrets of Migratory Fish Like Tuna
— Posted with permission of SEAFOODNEWS.COM. Please do not republish without their permission. —
Copyright © 2015 Seafoodnews.com
SEAFOODNEWS.COM [United Press International] By Brooks Hays - October 22, 2015By comparing the movements of tagged fish with ocean heat content maps, researchers at the University of Miami were able to uncover unique patterns in migratory fish behavior.Their analysis proves that large migratory fishes, like yellowfin and bluefin tunas, blue and white marlin, and sailfish, are drawn to ocean fronts and eddies.Two analytical breakthroughs made the revelation possible. First, researchers realized satellite mapping of ocean heat content, or OHC, a measurement of heat stored in the ocean's upper layers commonly used for hurricane forecasting, could also be used to pinpoint the position of fronts and eddies.Second, researchers were able to improve the algorithm that analyzes satellite tags from migratory fish. Together, these advances allowed researchers to compare OHC mapping and fish movements."Using an advanced optimization algorithm and OHC maps, we developed a method to greatly improve geolocation accuracy and refine fish movement tracks derived from satellite tags," lead researcher Jiangang Luo, a scientist at Miami's Tarpon and Bonefish Research Center, said in a press release.The data showed that large migratory fish prefer to follow the boundary lines of large water features."Using the OHC approach in a new way offers an unprecedented view of how these animals move with currents and eddies in the ocean," Nick Shay, a professor of ocean sciences at Miami's Rosenstiel School of Marine and Atmospheric Science, said in a press release. "Our study provides a more detailed picture of the ocean ecosystem as an entity."Eddies are circling masses of water that spin off of current fronts. The swirling water pulls nutrients to the surface, making them an ideal place for hungry fish to hang out. Fronts are currents that follow the boundary line between two large water masses, distinguished by a difference in temperatures or salinity.In the Gulf of Mexico, warm water eddies regularly spin off of fronts formed by masses of Mississippi River water. In the summer and fall, these eddies can energize and intensify a hurricane or tropical storm."Our new method shows that hurricanes and highly migratory fish share at least one common oceanographic interest -- warm swirling ocean eddies," said Jerald S. Ault, a professor of marine biology and ecology at Rosenstiel.The new research was detailed in a paper published this week in the journal PLOS ONE.
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Members rally, protest Atlantic Marine Monument proposal
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Plenty of anchovies in Monterey Bay, but maybe not elsewhere
Monterey >> Things are shifting for fishermen in Monterey Bay.Market squid are disappearing, and in their place, fishing boats are reeling in piles of anchovies.But while they appear abundant, conservation groups warn that the forage fish may be at their lowest levels since the 1950s.“It’s an anomalous year,” said Diane Pleschner-Steele, executive director of the California Wetfish Producers Association. “Typically these are not the kind of oceanographic conditions that anchovy like. But they are here and they’re really close to shore, which is why we’re having a spectacular year for whale watching.”Anchovies aren’t just bringing whales into the bay — they’re also attracting fishing fleets.“There are thousands of tons,” said Sal Tringali, president of Monterey Fish Company, whose fishermen in Moss Landing are landing about 120 tons of anchovies each night and expect to do so for about another month. “There are all the anchovies you want out here.”Tringali said the majority of his harvest never fills human bellies, as roughly 70 percent of the catch travels to Australia to feed tuna.Records from the California Department of Fish and Wildlife show that, across the state, fishermen landed 13,508 metric tons of anchovies this year.That number was fine in previous years, but now it’s dangerous, said Geoff Shester of conservation group Oceana.“This level of catch is sustainable when the stock is healthy,” Shester said. “But new information shows that the stock is at such a low level right now, it’s literally in a state of collapse.”Survey cruises conducted by the Southwest Fisheries Science Center detected little to no anchovy eggs from 2010 to 2013. The lack of eggs, coupled with a recent study still in review that suggests anchovy biomass has decreased by over 99 percent from 2005 to 2009, has Shester and his fellow conservationists concerned.“Every ton we can keep in the water is extremely valuable for the future of anchovies and the amazing multimillion-dollar whale-watching and wildlife-viewing destination that is Monterey Bay,” Shester said.Shester, along with representatives from four other conservation groups, recently sent a letter to the Pacific Fisheries Management Council, which oversees fisheries from Washington to California, urging the council to reconsider its anchovy management strategy and conduct a new stock assessment. They argue that because the last anchovy assessment was taken in 1995, current management policy doesn’t apply to modern numbers.Sit on the docks where anchovies are sorted and you’ll likely see lots of the silvery fish piling up. But it’s a mirage, warns William Sydeman, ecologist of the Farallon Institute, who coauthored the paper that estimated anchovies at low levels.“People think that if they’re in Monterey Bay, they must be everywhere,” Sydeman said. “They’re not. They’re only in Monterey Bay.”Sydeman said anchovies tend to aggregate near shore when their numbers are low, giving the appearance of abundance. When numbers are actually strong, he said, the fish expand offshore, disappearing from sight.“People think, ‘Oh look at all these whales, there must be a ton of fish,’ and that’s probably true,” said Sydeman. “There is a local abundance of anchovies. But it’s local. That doesn’t mean global abundance.”The National Marine Fisheries Service enforces a cap on anchovies. Josh Lindsay, policy analyst for the service, believes that number is conservative.“To take a precautionary approach,” Lindsay said, “we took the overfishing limit and told the fishing fleet that they could only catch 25,000 metric tons. That’s a pretty large buffer built into our management.”The Pacific Fishery Management Council will meet next month to review the latest findings on anchovy numbers.
Read the original post: www.montereyherald.com/
New research maps areas most vulnerable to ocean acidification
This map shows the global distribution of aragonite saturation at 50 meters depth. The graphic shows areas that are most vulnerable to ocean acidification since they are regions where the saturation of aragonite is lower. Aragonite is a calcium carbonate mineral that shellfish use to build their shells. Credit NOAA
New NOAA-led research maps the distribution of aragonite saturation state in both surface and subsurface waters of the global ocean and provides further evidence that ocean acidification is happening on a global scale. The study identifies the Arctic and Antarctic oceans, and the upwelling ocean waters off the west coasts of North America, South America and Africa as regions that are especially vulnerable to ocean acidification."These findings will help us better understand and develop strategies to adapt to the severity of ocean acidification in different marine ecosystems around the world," said Richard A. Feely, a NOAA oceanographer and co-author of the study, which has been accepted for publication and can be read online in the American Geophysical Union journal Global Biogeochemical Cycles.Ocean acidification is caused by humankind's release of carbon dioxide emissions to the atmosphere. Excess carbon dioxide enters the ocean, reacts with water, decreases ocean pH and lowers carbonate ion concentrations, making waters more corrosive to marine species that need carbonate ions and dissolved calcium to build and maintain healthy shells and skeletons. The saturation state of seawater for a mineral such as aragonite is a measure of the potential for the mineral to form or to dissolve.In the new study, scientists determined the saturation state of aragonite in order to map regions that are vulnerable to ocean acidification. Waters with higher aragonite saturation state tend to be better able to support shellfish, coral and other species that use this mineral to build and maintain their shells and other hard parts.This study shows that aragonite saturation state in waters shallower than 328 feet or 100 meters depth decreased by an average of 0.4 percent per year from the decade spanning 1989-1998 to the decade spanning 1998-2010. "A decline in the saturation state of carbonate minerals, especially aragonite, is a good indicator of a rise in ocean acidification," said Li-Qing Jiang, an oceanographer with NOAA's Cooperative Institute for Climate and Satellites at the University of Maryland and lead author.The most vulnerable areas of the global ocean are being hit with a double whammy of sorts. In these areas, deep ocean waters that are naturally rich in carbon dioxide are upwelling and mixing with surface waters that are absorbing carbon dioxide from the atmosphere. The carbon dioxide from the atmosphere is coming primarily from human-caused fossil fuel emissions."When oyster larvae are born they must draw on the energy in their yolk to build their aragonite shells to protect themselves from predators and grow into healthy adults," said Feely. In waters depleted of carbonate ions, young oysters must expend more energy to build their shell and may not survive. This has significant consequences for the seafood industry."
Read the original post: http://www.eurekalert.org/
'Ridiculously Resilient Ridge' retires, making room for rain
El Niño is expected to bring a low-pressure system, which will replace the high-pressure system that's exacerbated California's drought. nasa.gov
The high pressure system that has shunted storms away from California for much of the past four years has dissipated, possibly for a long time.The Ridiculously Resilient Ridge — as meteorologists and forecasters have dubbed the system because of its unusual persistence — has been absent for more than a month, according to a forecaster with the National Oceanic and Atmospheric Administration.“It hasn’t been like that since August really, and instead we’ve had sort of more variable weather patterns,” said Nate Mantua, a research scientist with NOAA’s Southwest Fisheries Science Center in Santa Cruz.Mantua said the ridge will likely stay away, because it will have been replaced by a low-pressure trough.“The expectations are as we get into Fall and Winter seasons more deeply, we’re going to see a lot more low pressure there, and that will be the more sort of dominant story,” Mantua said.Eric Boldt, a meteorologist with the National Weather Service in Oxnard, said low-pressure systems typically accompany El Niño events.“Lower pressure in the Eastern Pacific is a classic pattern you’d see with an El Niño setting up with the jet stream a little more to the south, and that’s were we get into our storm track coming up from the southwest across California,” Boldt said.The high-pressure ridge has created a large swath of unusually warm water off the coast. Boldt said the warm water would take months to dissipate and that its interaction with El Niño isn’t well understood. However, he said storms from strong El Niño events, which can bring heavy rains to California, could be bolstered by the warm water.“That’s the part that is a little bit unprecedented. We don’t really have a good idea about how that might impact us, but warmer ocean temperatures typically lead to fueling the atmosphere and kind of energizing those storms. So I don’t think it’s going to be a negative for us,” Boldt said.Mantua said the disappearance of the ridge and the presence of a strong El Niño is likely to produce a lot of rain in Southern California.“[The low-pressure system is] just another factor that sort of favors a more normal winter, although I don’t think it’s going to be normal. I think it’s going to be probably an exciting winter, especially for Southern California,” Mantua said.
Read/listen to the original post: http://www.scpr.org/
Pacific Bonito and Albacore Tuna Among Non-Native Fish Species Sighted in Alaska's Warmer Waters
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Copyright © 2015 Seafoodnews.com
What are you doing here? Unusual fish appear in AlaskaIt’s a fascinating time to be an Alaska fish biologist, charter operator or angler. With warmer ocean temperatures caused by El Nino and a phenomenon called "The Blob," bizarre fish sightings are pouring in from around the state, particularly Southeast.Scott Meyer, a state fishery biologist based in Homer, is amassing photos from colleagues and boat captains who have hauled in everything from a 900-pound ocean sunfish near Juneau to warm-water thresher sharks off the coast of Yakutat since July.“It’s unusual to have these fish caught in near-shore fisheries,” Meyer said.The warm-water mass nicknamed The Blob has been swirling around the Pacific Ocean for the past couple of years and moving north toward Alaska. At the same time, El Nino is in full force this year, a weather pattern characterized by unusually warm ocean temperatures. As a result, ocean conditions including temperatures and food sources for fish are changing and species not normally found in state waters are showing up.The peak of the 2015-2016 El Nino is approaching, with this year's event among the strongest on record, according to the National Oceanic and Atmospheric Administration.The Blob has raised temperatures in the North Pacific to record highs of about five to seven degrees Fahrenheit above average, according to NOAA.Joe Orsi, a federal fisheries biologist in Juneau, said two massive sunfish swam into researchers’ gear in Southeast this summer as they conducted juvenile salmon surveys. Sunfish tend to favor warmer waters than those found in Alaska.Other unusual reports include Pacific bonito caught in waters off Ketchikan, albacore tuna spotted near Prince of Wales Island, and yellow tail caught near Sitka.As recently as last Saturday, an ocean sunfish washed ashore outside a lodge in Cordova.Steve Moffitt, the state biologist who dissected the sunfish, said pilots and fishermen have reported several sightings of sunfish this summer. They were likely chasing the warmer currents and a huge mass of jellyfish that filled the waters around Cordova, he said.“Sunfish really like to eat jellyfish,” Moffitt said.California market squid are also starting to spawn in Southeast, Orsi said.While the usual fish sightings are interesting from a biological perspective, they may be a cause for concern, Orsi said. One of his top questions: if ocean temperatures rise, how will big-money fish like salmon be affected?The Alaska Department of Fish and Game forecast the Southeast pink salmon harvest in 2015 at 58 million fish, yet fishermen hauled in only about 34 million pinks, according to state records.Did The Blob and El Nino cause the low catch level? Hard to say definitively but it’s “certainly easy to point the finger at them,” said Dave Harris, Fish and Game’s commercial fishery management biologist in Juneau.“Those are the most likely suspects,” Harris said.
Copyright © 2015 Seafoodnews.com