Experiments suggest long term changes to the global carbon cycle are underway
Biological impacts of seawater pH have implications for the use of foraminifera as paleoceanographic indicators.
May 25, 2017 University of California – Davis Bodega Marine Lab ScienceDaily
… For the study, published in the journal Scientific Reports, scientists raised foraminifera — single-celled organisms about the size of a grain of sand — at the UC Davis Bodega Marine Laboratory under future, high CO2 conditions. These tiny organisms, commonly called “forams,” are ubiquitous in marine environments and play a key role in food webs and the ocean carbon cycle….UC Davis scientists found that under high CO2, or more acidic, conditions, the foraminifera had trouble building their shells and making spines, an important feature of their shells….[and] showed signs of physiological stress, reducing their metabolism and slowing their respiration to undetectable levels.
This is the first study of its kind to show the combined impact of shell building, spine repair, and physiological stress in foraminifera under high CO2 conditions. The study suggests that stressed and impaired foraminifera could indicate a larger scale disruption of carbon cycling in the ocean….
…As a marine calcifier, foraminifera use calcium carbonate to build their shells, a process that plays an integral part in balancing the carbon cycle. Normally, healthy foraminifera calcify their shells and sink to the ocean floor after they die, taking the calcite with them. This moves alkalinity, which helps neutralize acidity, to the seafloor. When foraminifera calcify less, their ability to neutralize acidity also lessens, making the deep ocean more acidic. …”That acidified water from the deep will rise again. If we do something that acidifies the deep ocean, that affects atmospheric and ocean carbon dioxide concentrations on time scales of thousands of years.” [Catherine] Davis said the geologic record shows that such imbalances have occurred in the world’s oceans before, but only during times of major change. “This points to one of the longer time-scale effects of anthropogenic climate change that we don’t understand yet,” Davis said.
…strong winds periodically push nutrient-rich water from the deep ocean up to the surface– Upwelling supports some of the planet’s most productive fisheries and ecosystems. But additional anthropogenic, or human-caused, CO2 in the system is expected to impact fisheries and coastal ecosystems…. UC Davis’ Bodega Marine Laboratory in Northern California is near one of the world’s most intense coastal upwelling areas. At times, it experiences conditions most of the ocean isn’t expected to experience for decades or hundreds of years.
“Seasonal upwelling means that we have an opportunity to study organisms in high CO2, acidic waters today — a window into how the ocean may look more often in the future,” said co-author Tessa Hill, an associate professor in earth and planetary sciences at UC Davis. “We might have expected that a species of foraminifera well-adapted to Northern California wouldn’t respond negatively to high CO2 conditions, but that expectation was wrong. This study provides insight into how an important marine calcifier may respond to future conditions, and send ripple effects through food webs and carbon cycling.”
Catherine V. Davis, Emily B. Rivest, Tessa M. Hill, Brian Gaylord, Ann D. Russell, Eric Sanford. Ocean acidification compromises a planktic calcifier with implications for global carbon cycling. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-01530-9
Abstract: ….We cultured a globally important calcifying marine plankter (the foraminifer, Globigerina bulloides) under an ecologically relevant range of seawater pH (7.5 to 8.3 total scale). Multiple metrics of calcification and physiological performance varied with pH. At pH > 8.0, increased calcification occurred without a concomitant rise in respiration rates. However, as pH declined from 8.0 to 7.5, calcification and oxygen consumption both decreased, suggesting a reduced ability to precipitate shell material accompanied by metabolic depression. Repair of spines, important for both buoyancy and feeding, was also reduced at pH < 7.7. The dependence of calcification, respiration, and spine repair on seawater pH suggests that foraminifera will likely be challenged by future ocean conditions. Furthermore, the nature of these effects has the potential to actuate changes in vertical transport of organic and inorganic carbon, perturbing feedbacks to regional and global marine carbon cycling. The biological impacts of seawater pH have additional, important implications for the use of foraminifera as paleoceanographic indicators.
Ocean currents affect how climate change impacts movements of species to cooler regions. A new study provides novel insight into how species’ distributions change from the interaction between climate change and ocean currents….
They found that species expanded their range faster and kept track of climate better when ocean currents matched the direction of warming. “We were expecting ocean currents to be most influential at the leading ‘cold’ edge of a species’ range, where warming represents an opportunity for the expansion of its range,” comments García Molinos. “In those situations it’s a little bit like a conveyor belt at an airport terminal. If you want to get to your boarding gate and you walk with the belt, you approach the gate faster than if you just stand on it passively. If you take the belt that goes in the opposite direction you will need to walk fast or even run to make progress.”
However, matching ocean currents and warming unexpectedly slowed down range contractions, or the speed of withdrawal at the “warm” edges. “This was somehow a surprise because we were expecting contraction rates to be mainly driven by the rate of warming,” says co-author Prof. Michael T. Burrows. ….”Our study suggests how directional forces such as ocean or air currents can influence the coupling between climate change and biogeographical shifts. Our simple metric can be used to improve predictions of distribution shifts and help explain differences in expansion and contraction rates among species,” concludes García Molinos.
J. García Molinos, M. T. Burrows, E. S. Poloczanska. Ocean currents modify the coupling between climate change and biogeographical shifts. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-01309-y
Before 1990, oceans were rising at about 1.1 millimeters per year, or just 0.43 inches per decade. From 1993 through 2012, though, it finds that they rose at 3.1 millimeters per year, or 1.22 inches per decade.
A new scientific analysis finds that the Earth’s oceans are rising nearly three times as rapidly as they were throughout most of the 20th century, one of the strongest indications yet that a much feared trend of not just sea level rise, but its acceleration, is now underway. “We have a much stronger acceleration in sea level rise than formerly thought,” said Sönke Dangendorf, a researcher with the University of Siegen in Germany who led the study along with scientists at institutions in Spain, France, Norway and the Netherlands.
Their paper, just out in the Proceedings of the National Academy of Sciences, isn’t the first to find that the rate of rising seas is itself increasing — but it finds a bigger rate of increase than in past studies. The new paper concludes that before 1990, oceans were rising at about 1.1 millimeters per year, or just 0.43 inches per decade. From 1993 through 2012, though, it finds that they rose at 3.1 millimeters per year, or 1.22 inches per decade.
The cause, said Dangendorf, is that sea level rise throughout much of the 20th century was driven by the melting of land-based glaciers and the expansion of seawater as it warms, but sea level rise in the 21st century has now, on top of that, added in major contributions from the ice sheets of Greenland and Antarctica.
“The sea level rise is now three times as fast as before 1990,” Dangendorf said….Kopp added that in the past five years, there is some indication that sea level rise could already be even higher than the 3.1 millimeter annual rate seen from 1993 through 2012. He cautioned, though, that “those higher rates over a short period of time probably include some level of natural variability as well as continued, human-caused acceleration.”…“Sea levels will continue to rise over the coming century, no matter whether we will adapt or not, but I think we can limit at least a part of the sea level rise. It will further accelerate, but how much is related to how we act as humans,” Dangendorf said
Maryland waters could be home to some of the nation’s first — and by far its largest — offshore wind farms after the state Public Service Commission on Thursday approved ratepayer subsidies to support a pair of projects off the coast of Ocean City….The decision could dot the Ocean City horizon with wind turbines as soon as 2020 — and add $1 to monthly residential electricity bills once the windmills start spinning. …
…“If built, these wind farms will be truly pioneering facilities, leading Maryland and the nation toward a 21st century economy that combats climate change and creates jobs in droves at the same time,” said Mike Tidwell, director of the Chesapeake Climate Action Network….
…The developers are required to build the turbines as far from shore as possible — up to 17 miles for the U.S. Wind farm and 24 miles for the Skipjack turbines. U.S. Wind officials have said that on a clear day, their turbines would appear to a person on the beach as about the size of a thumbnail at arms length…
Researchers are still studying the potential impacts such projects could have on wildlife, tracking migration patterns of birds such as red-throated loons to see how much they intersect with potential wind farm sites. Jennifer Mihills, of the Mid-Atlantic office of the National Wildlife Federation, said she thinks the projects “can be sited, constructed and operated in a manner that is protective of our coastal and marine wildlife.”…
The amount of dissolved oxygen contained in the water — an important measure of ocean health — has been declining for more than 20 years, reveals a new analysis of decades of data on oceans across the globe.
…Falling oxygen levels in water have the potential to impact the habitat of marine organisms worldwide and in recent years led to more frequent “hypoxic events” that killed or displaced populations of fish, crabs and many other organisms.
Researchers have for years anticipated that rising water temperatures would affect the amount of oxygen in the oceans, since warmer water is capable of holding less dissolved gas than colder water. But the data showed that ocean oxygen was falling more rapidly than the corresponding rise in water temperature.
“The trend of oxygen falling is about two to three times faster than what we predicted from the decrease of solubility associated with the ocean warming,” Ito said. “This is most likely due to the changes in ocean circulation and mixing associated with the heating of the near-surface waters and melting of polar ice.”….
….They found that air pollution drifting from East Asia out over the world’s largest ocean contributed to oxygen levels falling in tropical waters thousands of miles away. Once ocean currents carried the iron and nitrogen pollution to the tropics, photosynthesizing phytoplankton went into overdrive consuming the excess nutrients. But rather than increasing oxygen, the net result of the chain reaction was the depletion oxygen in subsurface water. That, too, is likely a contributing factor in waters across the globe, Ito said.
Takamitsu Ito, Shoshiro Minobe, Matthew C. Long, Curtis Deutsch. Upper Ocean O2 trends: 1958-2015. Geophysical Research Letters, 2017; DOI: 10.1002/2017GL073613
Climate change is predicted to cause a series of maladies for world oceans including heating up, acidification, and the loss of oxygen. A newly published study demonstrates that one ocean consequence of climate change that has already occurred is the spread and intensification of toxic algae.
Their study demonstrates that since 1982, broad stretches of these ocean basins have warmed and become significantly more hospitable to these algae and that new ‘blooms’ of these algae have become common in these same regions.Alexandrium and Dinophysis are serious health concerns as they make neurotoxins and gastrointestinal toxins that can cause paralytic and diarrhetic shellfish poisoning in humans.
…”The distribution, frequency and intensity of these events have increased across the globe and this study links this expansion to ocean warming in some regions of the North Atlantic and North Pacific Oceans,” Gobler said.
“A fundamental question has been whether we can directly link expansion of harmful algal blooms to a warming ocean; this paper provides critical, quantitative evidence for just that trend, confirming an expected, but difficult to test, direct link between toxic blooms to climate,” said Dr. Raphael Kudela, Professor of Ocean Sciences, University of California Santa Cruz, a national toxic algae expert who was not part of the study.
…”This study demonstrates that the global warming that has already occurred is now impacting human health and our oceans,” said Gobler. “An important implication of the study is that carbon emission and climate change-related policy decisions made today are likely to have important consequences for the fate of our future oceans, including the spread and intensification of toxic algal blooms.”
Christopher J. Gobler, Owen M. Doherty, Theresa K. Hattenrath-Lehmann, Andrew W. Griffith, Yoonja Kang, and R. Wayne Litaker. Ocean warming since 1982 has expanded the niche of toxic algal blooms in the North Atlantic and North Pacific oceans. PNAS, April 2017 DOI: 10.1073/pnas.1619575114
As the world continually emits carbon dioxide into the atmosphere, the oceans are taking a hit, absorbing some of it and growing more acidic. Among other effects, scientists have found that coral reefs and oyster hatcheries are deteriorating as a result. However, scientists studying a type of sea snail report a bit of bright news: The animal can adapt by rejiggering its shell-making process and other functions…
…While ocean acidification appears to cause damage to many calcifying organisms, recent studies have suggested that some of those organisms may be more resistant to acidification than previously thought. Sean D. Connell and colleagues wanted to find out how this might be possible.
The researchers exposed sea snails called periwinkles to the ocean conditions predicted for 2100, when some waters at a pH of 8.10 today are expected to reach a pH of 7.85. Although the animals’ metabolism declined, they were able to speed up their shell-making by producing less-dense inner shells. In addition, they developed less-soluble shells, which are more resistant to future, harsher ocean conditions. The researchers say these changes suggest that the periwinkle, and potentially other calcifying organisms, could have the ability to adapt to the acidifying oceans….
Jonathan Y. S. Leung, Bayden D. Russell, Sean D. Connell. Mineralogical Plasticity Acts as a Compensatory Mechanism to the Impacts of Ocean Acidification. Environmental Science & Technology, 2017; DOI: 10.1021/acs.est.6b04709
BOOTHBAY, Maine — Seaweed cultivation has been promoted in recent years in Maine as a way to produce local nutritious food and to boost the coastal economy.
Now, seaweed harvesters say their industry provides yet another benefit: environmental protection, in the form of improving water quality.
A new study from Bigelow Laboratory for Marine Sciences in Boothbay indicates growing and harvesting seaweed may be an antidote for increasing carbon and acidity levels in the ocean, which is harming a variety of marine life.
Since January 2016, the lab has been studying the effect of kelp growth on surrounding carbon levels at the Ocean Approved seaweed farm off Great Chebeague Island in Casco Bay…. According to Price, in the six months that scientists measured carbon dioxide levels in and around the 3-acre kelp farm, they found the kelp was absorbing carbon at the same rate carbon levels are expected to increase in the Gulf of Maine over the next 100 years from global use of fossil fuels….
Coccolithophores, single-celled calcifying phytoplankton that play a key role in the Earth’s climate system, might lose their competitive fitness in a future ocean. In a field experiment investigating the effects of ocean acidification on the coccolithophore Emiliania huxleyi in its natural environment, the species failed to bloom. A team of researchers concludes, that a small response to ocean acidification was amplified through ecological interactions and causes a massive impact on the ecosystem.
Photo:Dr. Jeremy R. Young Palaeontology Dept. The Natural History Museum LONDON, SW7 5BD, UK
…The uptake of fossil fuel carbon dioxide (CO2) by the ocean increases seawater acidity and causes a decline in carbonate ion concentrations. This process, termed ocean acidification, makes it energetically more costly for calcifying organisms to form their calcareous shells and skeletons. Several studies have shown that this also holds true for Emiliania huxleyi, the world’s most abundant and most productive calcifying organism….
…”In view of Emiliania‘s rather small changes in metabolic performance observed in previous laboratory experiments, we predicted that it would still be able to maintain its ecological niche in an acidifying ocean. What we observed came as a big surprise”…A small reduction in cellular growth due to ocean acidification caused the population size to gradually decline during the pre-bloom phase. “When it was time for Emiliania to start bloom formation, there were so few cells left in the plankton community that it couldn’t outgrow its competitors anymore,” reflects Ulf Riebesell….
The results of this study demonstrate the importance of investigating the effects of ocean acidification in natural communities….”If Emiliania huxleyi fails to maintain its important role, other, possibly non-calcifying, organisms take over. This might initiate a regime shift with far-reaching ecological and biogeochemical consequences,” Prof. Riebesell concludes.
Ulf Riebesell, Lennart T. Bach, Richard G. J. Bellerby, J. Rafael Bermúdez Monsalve, Tim Boxhammer, Jan Czerny, Aud Larsen, Andrea Ludwig, Kai G. Schulz. Competitive fitness of a predominant pelagic calcifier impaired by ocean acidification. Nature Geoscience, 2016; DOI: 10.1038/ngeo2854
The Block Island Wind Farm, consisting of five turbines off Rhode Island, sets up the possibility for offshore wind projects elsewhere along the coast…
…the Block Island Wind Farm is …made up of five turbines, which were built by a division of General Electric, and capable of powering about 17,000 homes — it is the first successful offshore wind development in the United States, and it sets up the possibility for offshore wind projects elsewhere along the coast.
…Mr. Trump has expressed skepticism of wind power, saying in an interview with The New York Times that “the wind is a very deceiving thing.” And an email written by Thomas J. Pyle, who is running the Department of Energy transition for the president-elect, said that the Trump administration may be looking to get rid of all energy subsidies.