Breaking Waves: Ocean News

10/30/2014 - 03:56
Unidentified drones had flown over seven plants this month by mystery operator as Greenpeace denies involvement Continue reading...
10/30/2014 - 01:17
Cape Melville rainbow skink and Cape Melville bar-lipped skink bring the tally of species unknown to science that have been found in small, remote area to eight Continue reading...
10/30/2014 - 01:00
Politicians who ignore message cannot in future say they take science seriously, open letter says Continue reading...
10/30/2014 - 00:30
RSPB calls on shooting industry to help stamp out problem as a report shows birds, including golden eagles, hen harriers and red kites were illegally killed last year Continue reading...
10/30/2014 - 00:30
Wicken Fen, Cambridgeshire A cacophony of voices heard beneath the old oak tree Continue reading...
10/29/2014 - 21:38
Australias global promise to cut emissions seems certain to test Greg Hunts determination to resist carbon pricing Continue reading...
10/29/2014 - 16:35
(Click to enlarge) Spanish hogfish at coral reef. (Credit: NOAA) This month, the U.N. Convention on Biological Diversity released a report updating the impacts of ocean acidification on marine life. (From Scientific American / by Jennifer Huizen and ClimateWire)–This time, it put estimated costs on the predicted damage, hoping to make governments aware of the potential size of the various threats. While many of the effects of growing acidification remain invisible, by the end of this century, things will have changed drastically, the report found. One estimate looking only at lost ecosystem protections, such as that provided by tropical reefs, cited an economic value of $1 trillion annually. Over the last 200 years, the world’s oceans have absorbed more than a quarter of the carbon dioxide released by humans, becoming 26 percent more acidic. Though technically waters have not yet become acidic, according to the pH scale, the report found this could occur by 2100 if emissions continue to rise. Though large, these changes are still difficult to comprehend, said Murray Roberts, a professor of marine biology at Heriot-Watt University in Edinburgh, Scotland, who co-edited the report. That’s why the economics of ocean acidification need to be discussed, he said. “We tried to give as much of an economic and governmental context as we could to the report, highlighting the areas we can work to change now,” said Roberts. “Yet there remains a huge level of uncertainty at this level; there just aren’t a great deal of key references to go by.” Roberts, who works with deep-sea corals, said the report is a starting point. While areas of study like his remain mostly elusive, work with tropical counterparts is generating the foundation for further work. “We used what we have right now,” he said, “which I think has generated the beginnings of what will become a much more detailed conversation.” Food security impact may be large Ocean acidification, first discussed in the 1990s, didn’t become a well-documented trend until 2004. But since then, the number of researchers entering the field has grown substantially. From 2004 to 2013, the report found, studies published on the topic grew twentyfold. “This alone warranted an update to the report,” said Roberts. But it wasn’t the only factor; the whole scope of the 2009 study needed to be altered to reflect reality, he explained. “In 2009, we didn’t take into consideration societal implications, loss of ecosystem services or policy at all,” said Roberts. “But by just looking at an example such as tropical reefs, it’s clear destruction of these reefs can lead to decreased food security, income loss, shoreline damage and much more.” The most recent report used four fundamental ecosystem services — provisional (food sources), regulatory, cultural and supporting services like coastal protection — as criteria to help characterize the impacts of acidification. Of the 400 million people cited to live within 62 miles of tropical reefs, many rely on these fish habitats for their livelihoods and a vast majority of their protein intake. So negative impacts on reefs represent a direct threat to human populations, explained Roberts. “Children watch ‘Finding Nemo’ and other such films, [which] is great and shows just how far we’ve come in educating the public about these environments, but most still think corals are a rock or a plant, not an animal,” he said. “Most of us remain divorced from the ocean.” The list of unknowns grows Philip Munday, a marine biologist at James Cook University in Queensland, Australia, who helped author the report, added: “Ocean acidification is a very young field, but if you look at what we’ve learned even in the past five years, it’s pretty encouraging. And realistically, a lot of the worst impacts we predict are decades out. This gives us time to make changes.” Munday, who has worked on the effects of warming and ocean acidification on fish, said that with rapid advancements in the field came whole new suites of unanticipated questions. A selection from Washington state’s oyster crop that is already suffering from ocean acidification. Photo courtesy of Gov. Jay Inslee. The 2009 study only looked at the impacts of acidification on calcifiers, organisms that build shells ranging from plankton to commercial crustaceans. It failed to consider genetic adaption potential, explained Munday. While shell-making species will certainly be affected by acidification, as the forms of elements they require to build and maintain their shells disappear under lower pH conditions, they are certainly not the only organisms at risk. “When I began, almost nothing was known about how fish would react to these kind of steady increases in carbon dioxide. Past studies all looked at instantaneous large increases and how organisms physiologically responded,” he said. On this front, fish have more flexibility, he said. Under high levels of CO2, fish can maintain internal pH by monitoring ions in their blood and accumulating bicarbonate, but at a cost of expended energy. “The question changes from whether fish can survive under future conditions to how much it will cost them to survive in these conditions,” he said. The report also found that shellfish have some adaptive capability. It described case of the northwest U.S. oyster populations. In 2006, some oyster hatcheries were experiencing mortality rates as high as 80 percent due to acidification accelerating the region’s already-low pH. But by recirculating water, keeping stock away from fluctuations and increasing feed, the industry has returned to normal rates in the past few years. Measures like this could also help protect fish populations, explained Munday, but he added that this might not necessarily be enough for species to adjust in time. Additional factors beyond the ability to function under decreased pH, like habitat loss and behavioral changes, he said, may present even more immediate threats to marine species. At lower pH levels, many fish loose their ability to understand chemical cues that help them learn their environment and avoid predators. Fish that lose their sense of predators “also expose themselves to further risk exhibiting bold behavior in the search for more food to meet their new energetic demands,” he explained. “These kind of findings could have never been anticipated; we found them by virtue of asking seemingly unrelated questions.” How fast can adaptation happen? Actual adaption potential remains one of the biggest unknowns, said Munday, and one of the biggest questions for the future, as will be adding in the other factors known to be simultaneously occurring in oceans worldwide. “Now we are tasked with looking at adaptive potential amidst the combined effects of acidification and warming,” he said. Roberts said while the report tried to frame recommendations in an obtainable light, focusing on goals that be implemented right away, like limiting construction debris, sewage and pollution levels, the ultimate task of actually decreasing carbon emissions is further off. “Emissions are of course the final and only real solution at the end of it all,” said Roberts, “but we’ve got to be realists. Renewable energy sources won’t be possible everywhere anytime soon, and the damage already done has been shown historically to take thousands of years to repair.” The last time the Earth’s oceans experienced these kinds of carbon dioxide changes, the report found, was 56 million years ago, during the Paleo-Eocene Thermal Maximum, or PETM, when 2,000 to 3,000 petagrams of CO2 was released over 10,000 years. The results killed a vast abundance of marine life, primarily calcifiers. Then it took the oceans roughly 100,000 years to rebalance. By comparison, today’s changes are occurring at 10 times this rate, with projections of PETM levels by 2600 if emission levels remain the same.
10/29/2014 - 16:02
(Click to enlarge) Satellite image showing a patch of bright waters associated with a bloom of phytoplankton in the Barents Sea off Norway. (Credit: Norman Kuring, Ocean Color Group at Goddard Space Flight Center, NASA) When we talk about global carbon fixation -“pumping” carbon out of the atmosphere and fixing it into organic molecules by photosynthesis — proper measurement is key to understanding this process. (From Science Daily / Weizmann Institute of Science)–By some estimates, almost half of the world’s organic carbon is fixed by marine organisms called phytoplankton — single-celled photosynthetic organisms that account for less than one percent of the total photosynthetic biomass on Earth. Dr. Assaf Vardi, a marine microbiologist in the Weizmann Institute’s Plant and Environmental Sciences Department, and Prof. Ilan Koren, a cloud physicist, and Dr. Yoav Lehahn, an oceanographer, both from Earth and Planetary Sciences Department, realized that by combining their interests, they might be able to start uncovering the role that these minuscule organisms play in regulating the carbon content of the atmosphere. Tiny as they are, phytoplankton can be seen from space: They multiply in blooms that can reach thousands of kilometers in area, coloring patches of the ocean that can be tracked and measured by satellites. These blooms have a tendency to grow quickly and disappear suddenly. How much carbon does such a bloom fix, and what happens to that carbon when the bloom dies out? That depends, in part on what kills the bloom. If it is mostly eaten by other marine life, for example, its carbon will be passed up the food chain. If the phytoplankton are starved or infected with viruses, however, the process is more complicated. Dead organisms that sink may take their carbon to the ocean floor with them. But others may be scavenged by certain bacteria the in surface waters; these remove the organic carbon and release it back into the atmosphere through their respiration. Vardi, Koren and Lehahn asked whether one can use the satellite data to detect the signs of the demise of a bloom due to viral infection, an occurrence that Vardi has investigated in natural oceanic blooms and in the lab. During a recent research cruise near Iceland with colleagues from Rutgers University and Woods Hole Oceanographic Institute, the researchers were able to collect data on the algal-virus interactions and their effect on carbon cycles in the ocean. By combining satellite data with their field measurements, they were able, for the first time, to measure the effect of viruses on phytoplankton blooms on large, open ocean areas. To do this, the scientists first had to identify a special subset of ocean patches in which such physical processes as currents did not affect the blooms — so they could observe just the biological effects. Then, following a bloom in one of these patches, they managed to trace its whole life cycle. This enabled them to quantify the role of viruses in the demise of this particular bloom. Their conclusions were verified in data collected in a North-Atlantic research expedition. The scientists estimated that an algal patch of around 1,000 sq km — which forms within a week or two — can fix around 24,000 tons of organic carbon — equivalent to a similar area of rain forest. Since a viral infection can rapidly wipe out an entire bloom, the ability to observe and measure this process from space may greatly contribute to understanding and quantifying the turnover of carbon cycle and its sensitivity to environmental stress conditions, including marine viruses.
10/29/2014 - 13:57
Nuclear safety expert claims there is significant risk due to poor condition of storage ponds containing highly radioactive fuel rods Continue reading...
10/29/2014 - 13:56
To understand the extent to which human activities are polluting Earth's atmosphere and oceans, it's important to distinguish human-made pollutants from compounds that occur naturally. A new study finds that deposition of ammonium, a source of nitrogen pollution, over the open ocean comes mostly from natural marine sources, and not from human activity.