Computer Models Show How Skyborne Seawater Particles Change Cloud Brightness, Temperature, Rain Patterns

Ships blowing off steam are helping researchers understand how human-made particles might be useful against global warming. New results from modeling clouds like those seen in shipping lanes reveal the complex interplay between aerosols, the prevailing weather and even the time of day the aerosol particles hit the air, according to research presented at the American Association for the Advancement of Science's annual meeting in San Diego.

"We've seen ship tracks affect the reflectivity of clouds," said Phil Rasch, chief climate scientist at the Department of Energy's Pacific Northwest National Laboratory in Richland, Wash. "We want to know if we can do the same thing when we want to, on purpose, and how that might be helpful in countering some of the effects of global warming."We decided to see how the reflectivity of clouds is influenced by particles in a very detailed model that treats clouds much more realistically than we are able to do in a typical climate model."Reflecting sunlight back into space prevents that energy from hitting Earth's surface. So brighter clouds could have an overall cooling effect compared to darker ones.A handful of research groups in the US are exploring geoengineering, or the intentional modification of Earth's climate, in hopes of developing tools that might be used to lower global temperatures if atmospheric greenhouse gases reach levels that might produce disastrous climate change.Previous work analyzing clouds in shipping lanes showed that large ships spewing tiny particles into the sky change the characteristics of clouds. More aerosol particles -- tiny natural or human-made bits of dirt, water and gas, such as from pollution -- increase the number of droplets in clouds and make each droplet smaller. This reflects more sunlight from the surface, and the clouds appear brighter.But the previous work revealed that some parts of the clouds above shipping lanes became brighter and other parts darker, suggesting that using aerosols to increase cloud reflectivity will be more complex than simply adding more."Do the brighter and darker parts cancel each other out?" asked Rasch.To find out, the group performed some exploratory computer simulations to determine the net effect of increased aerosols. His team simulated three ships chugging along in a 93-mile by 37-mile block of the Pacific Ocean a few hundred miles southwest of Los Angeles.The team showed that introducing additional particles into the model near the surface -- as proposed for geoengineering -- would make the clouds significantly more reflective than they would otherwise be, in certain situations. They found that if the clouds were already drizzling then the new particles would not brighten them very effectively.Rasch will discuss other cloud, weather and climate characteristics affected by aerosols, such as how long the brighter clouds last, whether they burn off when the sun comes up, and what happens when they finally rain. The team is also using the simulations to test when the best time to spray seawater using the simulations is -- in the morning, late afternoon or perhaps all night long.Although ship tracks are helping researchers explore geoengineering methods, the real plans won't use polluting aerosols from ships. Instead, Rasch and others suggest that ocean vessels could spray seawater aerosols into the sky to brighten clouds. But many questions remain about how effective, predictable and safe such methods might be.Rasch will also discuss results from a Community Climate System Model study. He and colleagues simulated what happens to the global climate as aerosol concentrations rise. The work, published December 2009 in Environmental Research Letters, showed increasing aerosols in the ocean air can either increase the amount of sea ice to previous levels, restore precipitation, or reduce temperatures, but not all at the same time.

Sound maps reveal whales and noise pollution

Land areas are not the only places getting busier: so too are the oceans, says a Cornell researcher who uses underwater recorders to create animated maps of the oceans' noise.Increasingly, the oceans are being polluted by shipping traffic noise, especially up and down the U.S. eastern and western seaboards. The cacophony interferes with the ability of whales and other sea animals to hear each other; they rely on quiet waters to communicate many miles apart."People have no idea the world in the ocean off the coast is so urbanized," said Christopher Clark, the I.P. Johnson Director of the Bioacoustics Research Program at the Cornell Lab of Ornithology, who discussed his state-of-the-art acoustic animations and the difficulties facing whales Feb. 21 at the American Association for the Advancement of Science (AAAS) annual meeting in San Diego.His research not only documents ocean noise and its repercussions but also tracks such endangered species as the North Atlantic right whale.Clark presented color animations that show time-elapsed maps of the sounds of passing whales and ships. Clark and colleagues placed arrays of recording devices spaced over the ocean floor for three months at a time. The devices were then retrieved, their terabytes of data analyzed at Cornell and transferred into a visual format."Now I can quantify how much [sound is generated] every time a ship comes through," Clark said. "It creates acoustic 'bleaching,' and you can measure how much acoustic space is lost by ships coming through. For example, every day right whales lose 80 to 85 percent of their opportunities to communicate as a result of ship traffic."Sound travels very efficiently in water and gets trapped in a layer of water known as a deep sound channel about half a mile deep, depending on latitude, Clark said. He likened diving into this channel to a curtain rising so that suddenly you can hear clearer and louder. He hypothesizes that whales' voices and hearing have evolved to communicate with each other over very large distances. "I can hear a blue whale that's singing off the Grand Banks of Canada while listening off Puerto Rico," Clark said.Although blue whales use very low frequencies that can travel such great distances, higher-pitched humpback whale singers can be heard only over a few hundred miles, and North Atlantic right whales over only tens of miles.But manmade sounds are now bleaching whales' underwater communication channels."Now we are listening to observe what the whales do as noise levels go up," Clark said.Some 60 years ago when there was little traffic noise, whales could hear each other pretty much all the time, except when storms came through. Then they would stop chattering, only to resume when the storm passed.But now, what do whales do amid the steady din? Using his acoustic techniques, Clark has found that as traffic noise increases or oil exploration vessels pound the sea floor, communication among whales breaks down, and sometimes the animals evacuate the area within hours to days.Clark also discussed the use of listening buoys off the coast of Massachusetts that automatically detect right whales and inform ship captains to slow down when a whale is in or near the shipping lanes.

Marine Lab Hunts Subtle Clues to Environmental Threats to Blue Crabs

The Atlantic blue crab, Callinectes sapidus, long prized as a savory meal at a summer party or seafood restaurant, is a multi-million dollar source of income for those who harvest, process and market the crustacean along the U.S. Atlantic and Gulf coasts.Unfortunately, the blue crab population has been declining in recent years under the assault of viruses, bacteria and man-made contaminants. The signs of the attack often are subtle, so researchers from the National Institute of Standards and Technology (NIST) and the College of Charleston (CofC) are at work trying to identify the clues that will finger specific, yet elusive, culprits.Pathogens and pollutants impair the blue crab's metabolic processes, the chemical reactions that produce energy for cells. These stresses should cause tell-tale changes in the levels of metabolites, small chemical compounds created during metabolism. Working at the Hollings Marine Laboratory (HML) in Charleston, S.C., the NIST/CofC research team is using a technology similar to magnetic resonance imaging (MRI) to identify and quantify the metabolites that increase in quantity under common environmental stresses to blue crabs -- metabolites that could be used as biomarkers to identify the specific sources.In a recent paper in Metabolomics, the HML research team describes how it used nuclear magnetic resonance (NMR) spectroscopy to study challenges to one specific metabolic process in blue crabs: oxygen uptake. First, the researchers simulated an environmentally acquired bacterial infection by injecting crabs with the bacterium Vibrio campbellii. This pathogen impairs the crab's ability to incorporate oxygen during metabolism. Using NMR spectroscopy to observe the impact on metabolite levels, the researchers found that the yield of glucose, considered a reliable indicator of mild oxygen starvation in crustaceans, was raised.In a second experiment, the HML team mimicked a chemical pollutant challenge by injecting blue crabs with a chemical (2,4-dinitrophenol (DNP)) known to inhibit oxidative phosphorylation, a metabolic process that manufactures energy. This time, the metabolite showing up in response to stress was lactate, the same compound seen when our muscles need energy and must take in oxygen to get more produced. A rise in the amount of lactate proved that the crabs were increasing their oxygen uptake in response to the chemical exposure."Having the glucose and lactate biomarkers -- and the NMR spectroscopy technique to accurately detect them -- is important because the blue crab's responses to mild, non-lethal metabolic stresses are often so subtle that they can be missed by traditional analyses," says Dan Bearden, corresponding author on the HML paper.The research was supported in part by the National Science Foundation.The HML is a partnership of governmental and academic agencies including NIST, NOAA's National Ocean Service, the South Carolina Department of Natural Resources, the College of Charleston and the Medical University of South Carolina.

Ice Is 'Rotten' in the Beaufort Sea

Recent observations show that Beaufort Sea ice was not as it appeared in the summer of 2009. Sea ice cover serves as an indication of climate and has implications for marine and terrestrial ecosystems.

In early September 2009, satellite measurements implied that most of the ice in the Beaufort Sea either was thick ice that had been there for multiple years or was thick, first-year ice.

However, in situ observations made in September 2009 by Barber et al. show that much of the ice was in fact "rotten" ice -- ice that is thinner, heavily decayed, and structurally weak due to a uniform temperature throughout.

The authors suggest that satellite measurements were confused because both types of ice exhibit similar temperature and salinity profiles near their surfaces and a similar amount of open water between flows. The authors note that while an increase in summer minimum ice extent in the past 2 years could give the impression that Arctic ice is recovering, these new results show that multiyear ice in fact is still declining.

The results have implications for climate science and marine vessel transport in the Arctic.

The research appears in the journal Geophysical Research Letters.

Authors include David G. Barber, Ryan Galley, Matthew G. Asplin, Kerri-Ann Warner and Mukesh Gupta, Centre for Earth Observation Science, Faculty of Environment, Earth and Resources, University of Manitoba; Roger De Abreu, Canadian Ice Service, Environment Canada; Monika Pućko, Centre for Earth Observation Science, Faculty of Environment, Earth and Resources, University of Manitoba, and Freshwater Institute, Fisheries and Oceans; Simon Prinsenberg, Bedford Institute of Oceanography, Fisheries and Oceans; Stéphane Julien, Laurentian Region, Canadian Coast Guard.

Arctic polar bears imperilled by man-made pollution

The long term survival of polar bears is being threatened by man-made pollution that is reaching the Arctic.

This conclusion comes from a major review of research into how industrial chemicals such as mercury and organochlorines affect the bears.

The review suggests that such chemicals have a range of subclinical effects.

When added together, these can have a dramatic and potentially fatal impact on the bears' bones, organs and reproductive and immune systems.

The review, an analysis of more than a decade's research into the effect of pollution on bears, is published in the journal Environment International. After being very sceptical, I now feel that the impact on bears may be true

A range of man-made pollutants reach the polar Arctic region, carried there in the air and water.

These include toxic metals such as mercury, organohalogen contaminants (OHCs) including organochlorines, and polybrominated diphenyl ethers (PBDEs) and perflourinated compounds (PFCs), which are used industrially in insulating fluids, as coolants, in foams and electronics and as pest control agents.

Such chemicals are often fat-soluble and accumulate in the fat of many animals, which are then eaten by top predators such as polar bears.

These top predators are then exposed to increasingly concentrated levels of toxins.

But the impact of these toxins on polar bears has been difficult to measure, with the only previous studies done by the Arctic Monitoring and Assessment Programme in 1998 and 2004.

That is party because it is logistically difficult to take many and repeated samples of blood or tissue from live polar bears.

Also, only free-ranging healthy animals that are not clinically sick tend to be sampled, making the overall population appear to be healthier than it already is.

Shrinking sexual ability: studies have found correlations between levels of OHCs and smaller and deformed sexual organs in male and female bears
Overactive organs: organochlorines increase the activity of liver enzymes, while mercury boosts stress hormones in the blood
Mercury damages the bears' nervous systems
PCB exposure may lead to decreases in bone mass density
So veterinary scientist and polar bear expert Dr Christian Sonne, of the Department of Arctic Environment at Aarhus University in Denmark, conducted the first review of all pertinent research on the health effects of such contaminants on polar bears.

Previously, Dr Sonne was part of a team of researchers which found that "stress" linked to pollutants and shrinking sea ice appeared to be shrinking polar bears.

His new analysis includes the results of more than 200 organ and skull tissue samples taken from 80 bears in East Greenland between 1999 and 2009, as well as repeated measurements and observations of bears living in the Svalbard archipelago, Norway.

These studies reveal a number of ill-effects associated with industrial pollutants.

However, such studies can only show that contaminant levels are correlated with ill-effects, not that they cause them.

So Dr Sonne investigated the direct impacts of Arctic pollutants on two other top predators living in the region, Norwegian Arctic foxes and Greenland sledge dogs.

In 2003, researchers started a two-year study in which they fed Arctic foxes clean or contaminated whale blubber. One fox of a pair of brothers was fed clean food as a control, while the other brother ate contaminated food.

Having eliminated all other influences, such as gender and age, the researchers showed that foxes exposed to environmental levels of pollutants do suffer harmful effects.

For example, PCBs trigger decreases in bone density and damage the liver, mercury and organochlorines cause renal lesions, while OHCs alter the amount of vitamins circulating in the blood.

Similar effects were found in comparable studies on Greenland sledgedogs.

The maximum sea ice extent is declining by about 2.7% per decade
"Polar bear studies are correlative, but that is not conclusive as being 'cause and effect'," explains Dr Sonne.

"So including dogs and foxes as model species is important [because] you use species that are much like polar bears, and the species were exposed to similar food items as polar bears."

The impact on the bears is likely to be greater even than those effects which show up in studies.

"It is really important to understand that all organ systems are tied together," says Dr Sonne.

So individual pollutants may only have subtle, non-clinical effects on particular parts of a bear's body.

But in concert, the overall impact can be devastating, reducing an individual bear's ability to hunt, reproduce and resist disease.

"After being very sceptical, I now feel that the impact on bears may be true," says Dr Sonne.

He also concludes that climate change will exacerbate the impact of pollutants on the bears.

As the level of sea ice declines with warming temperatures, polar bears are fasting for longer.

That may mean they eat fewer seals and therefore less pollutants overall.

But they will have to burn fat to compensate.

That will release greater concentrations of toxins from their fat stores into their blood, says Dr Sonne.

This will cause further illness, weakening bears that will already be in poorer condition and may be exposed to new and more virulent pathogens capable of surviving in a warmer Arctic.

Dr Sonne's research is published a week after another separate study published in the journal Arctic showed that polar bears in the southern Beaufort Sea in the Arctic Ocean are occurring more frequently on land and open water, and less on the ice.

Warmer Climate Not The Cause Of Oxygen Deficiency In The Baltic Sea

Oxygen deficiency in the Baltic Sea has never been greater than it is now. But it is not an effect of climate change but rather of increased inputs of nutrients and fertilisers. This is the finding of researchers at the University of Gothenburg, Sweden, who have analysed the ocean climate of the Baltic Sea since the 16th century.

85 million people live in the drainage basin of the Baltic Sea. This population has a great impact on the marine environment of the Baltic. This is shown by the researcher Daniel Hansson at the Department of Earth Sciences, who has analysed the ocean climate of the Baltic Sea since the 16th century using new methods.

Human activity

In his thesis, Hansson notes that oxygen deficiency and spread of dead seabeds in the Baltic Sea are essentially due to human activity.

"Climate change to date has only had a negligible effect on oxygen deficiency in the Baltic Sea. The principal cause of oxygen deficiency and large areas of dead seabed is that inputs from agriculture and untreated wastewater increased sharply, in particular in conjunction with increased use of commercial fertiliser in the mid-20th century," says Hansson.

New methods

By combining new methods to reconstruct the historical climate and modern computer models, Hansson has been able to study in detail changes in water temperature, ice extent, river runoff, salinity and oxygen concentrations in the Baltic Sea over 500 years. The studies show clearly that the oxygen condition today cannot be compared with any other period since the 16th century, and that the present-day raised water temperature and limited ice extent are similar to situations that have occurred only twice previously.

Changes can come

"But if the trend towards continued warming persists, we may soon see climate change outside the variation that has occurred in the past 500 years," says Hansson.

The technique used in the thesis provides very high time resolution. Hansson has, for example, been able to reconstruct how the ice thickened during the turbulent days of January and February 1658, when King Charles X Gustav marched with the Swedish Army across the Little and Great Belt, leading to the annexation of Blekinge, Skåne, Halland and Bohuslän by Sweden.

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Adapted from materials provided by University of Gothenburg.

Human Impacts And Environmental Factors Are Changing The Northwest Atlantic Ecosystem

Fish in U.S. waters from Cape Hatteras to the Canadian border have moved away from their traditional, long-time habitats over the past four decades because of fundamental changes in the regional ecosystem, according to a new report by NOAA researchers.

The 2009 Ecosystem Status Report also points out the need to manage the waters off the northeastern coast of the United States as a whole rather than as a series of separate and unrelated components.
Known as the Northeast U.S. Continental Shelf Large Marine Ecosystem (NES LME), the ecosystem spans approximately 100,000 square miles and supports some of the highest revenue-generating fisheries in the nation. During the past 40 years, the ecosystem has experienced extensive fishing by domestic and foreign fleets, changes in ocean water temperatures due to climate change, and pressures from increasing human populations along the coast.
Michael Fogarty, who heads the Ecosystem Assessment Program at the Northeast Fisheries Science Center (NEFSC) of NOAA's Fisheries Service in Woods Hole, Mass., says his team's report highlights the need to understand natural and human-related changes in this region and to develop effective management and mitigation strategies.
"There are many pressures on the ecosystem including fishing, pollution, habitat loss from coastal development, and impacts on marine life from shipping and other uses of the ocean," Fogarty said. "In addition, changing climate conditions are warming ocean waters, changing ocean chemistry and circulation patterns, and altering atmospheric systems. These changes have, in turn, been linked to changes in the distribution and abundance of fish species in the region and their major sources of food."
The report is the first in a planned series of ecosystem status reports by Fogarty and his colleagues in the NEFSC's Ecosystem Assessment Program to document changes in the NES LME, one of 64 regions in the world's ocean designated as a large marine ecosystem. LMEs are large coastal ocean waters adjacent to continents and characterized by distinct bathymetry, hydrology, productivity and inter-related marine populations. LMEs produce 80 percent of the world's annual fishery yields, and most of the impacts of human activities in the ocean occur within their waters.
Some of the highlights of the program's first report:
Warming of coastal and shelf waters has led to northward shifts in distribution of some fish species and changes to a warmer-water fish community.
The community structure of zooplankton, a major food source for whales and many other marine species including fish, has changed, due in part to climate and physical processes acting over the North Atlantic Basin, indicating the importance of winds and atmospheric circulation patterns to the function and structure of this ecosystem.
Species-selective harvesting patterns have also contributed to shifts in the composition of the ecosystem, which is now dominated by small pelagic fishes such as herring and mackerel, shellfish species, and elasmobranchs (skates and small sharks) of relatively low economic value.
The trajectory of regional human population size suggests that human-induced pressure on the ecosystem will continue to increase.
The Northeast U.S. Continental Shelf is classified as experiencing ecosystem overfishing, although marked improvement has occurred in the condition of a number of harvested species. Exploitation rates, or the rate at which fish are removed from the ocean, have been significantly reduced in many fish stocks during the last decade, indicating that management measures put in place to reduce overfishing are beginning to show dividends.
Fogarty says sustained long-term monitoring by many agencies and institutions in the Northeast region has enabled scientists and others to trace changes in the ecosystem.
"In the future, we need to continue to monitor the oceanographic, ecological, and human indicators analyzed in this report to detect any additional changes in the system. These indicators also provide important inputs to models that can be used to help guide management decisions and to forecast future changes."
Adapted from materials provided by NOAA Fisheries Northeast Fisheries Science Center.

Humans 'Damaging The Oceans' In Profound Ways

There is mounting evidence that human activity is changing the world’s oceans in profound and damaging ways.

Man-made carbon emissions “are affecting marine biological processes from genes to ecosystems over scales from rock pools to ocean basins, impacting ecosystem services and threatening human food security,” the study by Professor Mike Kingsford of the ARC Centre of Excellence for Coral Reef Studies and James Cook University and colleague Dr Andrew Brierley of St Andrews University, Scotland, warns.
A new review, published in the latest issue of the journal Current Biology, says that rates of physical change in the oceans are unprecedented in some cases, and change in ocean life is likely to be equally quick.
These include changes in the areas fish and other sea species can inhabit, invasions, extinctions and major shifts in marine ecosystems.
“In the past, the boundaries between geological ages are marked by sudden losses of species. We may now be entering a new age in which climate change and other human-caused factors such as fishing are the major threats for the oceans and their life,” Andrew and Mike say.
“Given how essential the oceans are to how our entire planet functions it is vital that we intervene before more tipping points are passed and the oceans go down the sort of spiral of decline we have seen in the world’s tropical forests and rangelands, for example.”
Man-made carbon emissions are now above the ‘worst case’ scenario envisioned by the Intergovernmental Panel on Climate Change (IPCC), causing the most rapid global warming seen since the peak of the last Ice Age. At the same time the carbon is acidifying the oceans, with harmful consequences for certain plankton and shellfish.
“At current emission rates it is possible we will pass the critical level of 450 parts per million CO2 in the atmosphere by 2040. That’s the level when, it is generally agreed, global climate change may become catastrophic and irreversible,” they add. “At that point we can expect to see the loss of most of our coral reefs and the arctic seas.”
“The climate is currently warming faster than the worst case known from the fossil record, about 56 million years ago, when temperatures rose about 6 degrees over 1000 years. If emissions continue it is not unreasonable to expect … warming of 5.5 degrees by the end of this century.”
Scientists expect ocean oxygen levels to decline by about six per cent for every one degree increase in temperature and areas in the sea which are low in oxygen to grow by at least 50 per cent. This has major implications for the world’s most productive fishing waters in the cool temperate regions. The seas provide around one sixth of humanity’s protein food – and any loss in fisheries production will have a direct impact on us, he adds.
Besides the changes induced by carbon emissions, the oceans are also under assault from over-fishing, increased UV exposure, toxic pollution, alien species and disease. The combined effect is to weaken the ability of many species to withstand these multiple stresses.
Another risk is that warming will unlock vast reserves of frozen methane in the seabed, triggering uncontrollable, runaway global warming.
“In the face of such terrifying changes even large scale interventions such as establishment of very large networks of Marine Protected Areas are unlikely to be effective,” Mike cautions. “On a global scale, an immediate reduction in CO2 emissions is essential to minimize future human-induced climate change.”
The oceans can also play a role in the proposed solution of eliminating carbon emissions, by producing clean energy from wind, wave and tide – potentially – by triggering phytoplankton blooms with fertilisers to absorb more carbon from the atmosphere, or using the seabed to store CO2. However these require far more research to be sure.
“It may already be too late to avoid major irreversible changes to many marine ecosystems. As history has shown us, these marine-based changes could have major earth-system consequences,” the scientists conclude.
Journal reference:
Andrew S. Brierley, and Michael J. Kingsford. Impacts of climate change on marine organisms and ecosystems. Current Biology, 2009; DOI: 10.1016/j.cub.2009.05.046
Adapted from materials provided by ARC Centre of Excellence in Coral Reef Studies.

Scientists study huge plastic patch in Pacific

Marine scientists from California are venturing this week to the middle of the North Pacific for a study of plastic debris accumulating across hundreds of miles (km) of open sea dubbed the "Great Pacific Garbage Patch."A research vessel carrying a team of about 30 researchers, technicians and crew members embarked on Sunday on a three-week voyage from the Scripps Institution of Oceanography, based at the University of California at San Diego.The expedition will study how much debris -- mostly tiny plastic fragments -- is collecting in an expanse of sea known as the North Pacific Ocean Gyre, how that material is distributed and how it affects marine life.The debris ends up concentrated by circular, clockwise ocean currents within an oblong-shaped "convergence zone" hundreds of miles (km) across from end to end near the Hawaiian Islands, about midway between Japan and the West Coast of the United States.The focus of the study will be on plankton, other microorganisms, small fish and birds."The concern is what kind of impact those plastic bits are having on the small critters on the low end of the ocean food chain," Bob Knox, deputy director of research at Scripps, said on Monday after the ship had spent its first full day at sea.The 170-foot vessel New Horizon is equipped with a laboratory for on-board research, but scientists also will bring back samples for further study.Little is known about the exact size and scope of the vast debris field discovered some years ago by fishermen and others in the North Pacific that is widely referred to as the "Great Pacific Garbage Patch."Large items readily visible from the deck of a boat are few and far between. Most of the debris consists of small plastic particles suspended at or just below the water surface, making it impossible to detect by aircraft or satellite images.The debris zone shifts by as much as a thousand miles north and south on a seasonal basis, and drifts even farther south during periods of warmer-than-normal ocean temperatures known as El Nino, according to information from the National Oceanic and Atmospheric Administration (NOAA).Besides the potential harm to sea life caused by ingesting bits of plastic, the expedition team will look at whether the particles could carry other pollutants, such as pesticides, far out to sea, and whether tiny organisms attached to the debris could be transported to distant regions and thus become invasive species.

Threats To California's Cordell Bank Marine Sanctuary

A new NOAA report on the health of Cordell Bank National Marine Sanctuary indicates that the overall condition of the sanctuary’s marine life and habitats is fair to good, but identifies several emerging threats to sanctuary resources.

“Global issues of concern such as marine debris, ocean acidification and invasive species have the potential to degrade fragile sanctuary resources and habitats,” said Dan Howard, sanctuary superintendent. “This report provides a baseline for monitoring changes to sanctuary resources and will help us to better understand and respond to these emerging threats.”
Prepared by NOAA's Office of National Marine Sanctuaries, the peer-reviewed Cordell Bank National Marine Sanctuary Condition Report indicates that water quality in the sanctuary is generally good due to the sanctuary’s offshore location and distance from major urban population centers. Seafloor habitat quality was rated lower, primarily due to prior impacts from fishing gear that came into contact with the sanctuary’s rocky reef and soft sediment habitats.
The report notes that populations of rockfish, salmon, some seabird species, and leatherback sea turtles that use the sanctuary are depleted, but that fishery closures are helping to rebuild depleted fish stocks.
The report indicates that additional research is needed about contaminants and invasive species. While no maritime archaeological resources have been identified in the sanctuary, only 18 percent of the sanctuary seafloor has been mapped with high resolution tools that could be used to find sunken vessels.
The full sanctuary condition report is now available online. Similar reports are being developed for the other sites in the National Marine Sanctuary System.
Located 42 miles north of San Francisco, Cordell Bank National Marine Sanctuary is one of 14 marine protected areas managed by NOAA’s Office of National Marine Sanctuaries. Designated by Congress in 1989, the sanctuary’s productive waters are a destination feeding area for local and migratory marine life. Its unique rocky undersea thrives with invertebrates and fishes and is surrounded by the softer sediments of the continental shelf.
Adapted from materials provided by National Oceanic and Atmospheric Administration.

Arctic Contamination: Mercury In Mackenzie River Delta Dramatically Higher Than Previously Believed

University of Alberta researchers conducting a water study in the Mackenzie River Delta have found a dramatically higher delivery of mercury from the Mackenzie River to the Arctic Ocean than determined in previous studies.

Researcher Jennifer Graydon analyzed water in the Mackenzie River as it flowed north into the Beaufort Sea. She collected samples for three months and discovered the total amount of mercury exported from the river during that three-month period was equal to an entire year's worth of mercury calculated in previous studies.
Graydon's research and previous studies measured export of all chemical forms of mercury in water including methyl mercury.
"Methyl mercury is a neurotoxin and it's primarily passed on to humans through contaminated fish muscle," Graydon said. "This leaves northern communities vulnerable, because a large part of their diet is Arctic fish species and Beluga whales." Gradyon says existing studies already show Beluga whales in the western Arctic have higher mercury levels in their flesh than Belugas in the eastern Arctic. The Mackenzie River empties in the Beaufort Sea at the western edge of the Northwest Territories.
Graydon's new estimates were confined to the three months the research team spent on the delta while previous research used data to model mercury export over the course of an entire year.
"Previous annual mercury delivery estimates are premature because of the understudied effects of spring ice-jamming and of 45,000 delta lakes," said Graydon. "That influence water chemistry as the Mackenzie River passes through the delta."
"There are very few point sources for mercury in the Arctic," said Graydon. "Mercury is a metal that undergoes long range transport so the Arctic is getting mercury from a global pool." Graydon says the biggest contributor of man-made mercury pollution is coal-fired power production.
This summer U of A researchers will return to the Mackenzie region after it floods to study mercury levels in the thousands of lakes in the delta when flooded by the river. Graydon's Mackenzie River research was published in the journal Science of the Total Environment earlier this year.
Adapted from materials provided by University of Alberta, via EurekAlert!, a service of AAAS.

How Mercury Gets into our Seafood

The US Geological Survey published a study today that describes the mechanism by which anthropogenic mercury gets into the seas and into the seafood we eat. While it has been surmised that human use and emissions of Mercury were the source of mercury in the oceans and seafood, the mechanism by which anthropogenic mercury gets there has not been known.A new landmark study published today documents for the first time the process in which increased mercury emissions from human sources across the globe, and in particular from Asia, make their way into the North Pacific Ocean and as a result contaminate tuna and other seafood. Because much of the mercury that enters the North Pacific comes from the atmosphere, scientists have predicted an additional 50 percent increase in mercury in the Pacific by 2050 if mercury emission rates continue as projected."This unprecedented USGS study is critically important to the health and safety of the American people and our wildlife because it helps us understand the relationship between atmospheric emissions of mercury and concentrations of mercury in marine fish," said Secretary of the Interior Ken Salazar."This study gives us a better understanding of how dangerous levels of mercury move into our air, our water, and the food we eat, and shines new light on a major health threat to Americans and people all across the world," said EPA Administrator Lisa P. Jackson. "With this information in hand, plus our own mercury efforts, we have an even greater opportunity to continue working with our international partners to significantly cut mercury pollution in the years ahead and protect the health of millions of people."One unexpected finding from this study is the significance of long-range transport of mercury within the ocean that originates in the western Pacific Ocean, off the coast of Asia. Scientists sampled Pacific Ocean water from 16 different sites between Honolulu, Hawaii and Kodiak, Alaska. In addition, the scientists constructed a computer simulation that links atmospheric emissions, transport and deposition of mercury, and an ocean circulation model. ENN

Death From Above for Plankton

Nutrient-rich particles sifting out of the atmosphere can be a boon for phytoplankton, the tiny floating algae that support ocean food webs. But new research suggests that some particles are poisoning phytoplankton, potentially disrupting marine ecosystems and altering the amount of greenhouse gases withdrawn from the atmosphere.These atmospheric particles, or aerosols, can be natural or humanmade and include mineral-rich dust, soot, organic molecules, and sea salt crystals. Previous studies have emphasized the benefits of aerosol deposition in the ocean. This delivers high concentrations of phosphate, nitrogen, and iron that stimulate growth of phytoplankton. But aerosols don't contain only nutrients. They're a dry cocktail of substances that also include pollutants responsible for acid rain. Until now, scientists have overlooked their potential harm to the ocean. Oceanographer Adina Paytan of the University of California, Santa Cruz, and colleagues wanted to get a wider view of aerosols' effects on ocean productivity, so they decided to determine how several components of aerosols, not just the nutrients, affected phytoplankton communities in the Red Sea. The team collected aerosols blowing in from Europe and Africa and mixed them with water samples from the Red Sea. Phytoplankton exposed to the European samples thrived, but the ones mixed with the African aerosols took a nose-dive. The researchers noticed that the aerosols derived from Africa had nearly three times as much copper as the European samples. Further experiments confirmed that the copper levels in African aerosols are lethal to two groups of phytoplankton, as the team reports online this week in the Proceedings of the National Academy of Sciences. To get a global view of the possible impact, Paytan and her team modeled the amount of copper deposition in the oceans. They identified two hot spots for human-induced copper deposition: the Bay of Bengal just east of India, and areas in the Pacific Ocean near southeast Asia and China. Paytan says that phytoplankton in these areas may be more sensitive to the toxic element because they probably aren't accustomed to the current levels, which are globally 50% higher than before the industrial revolution. "This is a useful heads-up to a potential new problem," says marine and atmospheric chemist Alex Baker of the University of East Anglia in the U.K. Bill Landing, an oceanographer at Florida State University in Tallahassee, says that although extrapolating their findings to the world's oceans may be a bit premature, the study is a good first step. "They do a good job of pointing out the potential impacts, and most of them aren't good," he says.

Cause Of Mussel Poisoning Identified

The origin of the neurotoxin azaspiracid has finally been identified after a search for more than a decade.

The azaspiracid toxin group can cause severe poisoning in human consumers of mussels after being enriched in the shellfish tissues. The scientific periodical European Journal of Phycology reports in its current issue (Vol. 44/1: p. 63-79) that a tiny algal species, the dinoflagellate Azadinium spinosum, is responsible.
Researchers from the Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association have isolated and described the hitherto unknown organism as a new genus and species of dinoflagellate. They successfully isolated the organism and multiplied it in pure laboratory cultures, subsequently identifying it as the producer of azaspiracid toxin.
Eating mussels is a special treat for many people, although it is not completely without danger. It has been known for a long time that consumption of mussels and other bivalve shellfish can cause poisoning in humans, with symptoms ranging from diarrhea, nausea, and vomiting to neurotoxicological effects, including paralysis and even death in extreme cases. Although "shellfish poisoning" can also be caused by pathogenic viruses and bacteria, many cases are due to gastrointestinal toxins and/or neurotoxins produced by certain marine microscopic plankton, the so-called "toxic algae". Mussels can filter a high amount of these toxic microorganisms from the seawater column, and after ingestion they retain the toxins and accumulate them in their edible flesh.
Azaspiracids comprise one group of these microalgal toxins The first known azaspiracid poisonings occurred in the Netherlands in 1995 after consumption of mussels from Ireland. While the toxin itself has been quite well investigated, the question of the origin remained inconclusive until now despite intensive research. According to published investigations by Irish researchers, the dinoflagellate species Protoperidinium crassipes (previously regarded as harmless) has been blamed as the origin of the toxins since 2003.
Researchers from the Working Group on Ecological Chemistry, particularly the biologist Dr. Urban Tillmann and the chemist Dr. Bernd Krock from the Alfred Wegener Institute for Polar and Marine Research were able to show that Protoperidinium is only the vector and not the producer of the toxins, just like other voracious protozoa and mussels. They isolated a small alga from the North Sea off the Scottish east coast and described it as a new dinoflagellate species Azadinium spinosum while providing evidence of its azaspiracid production in the laboratory.
"We are able to produce so-called gene probes from our laboratory cultures with the help of molecular techniques", explains Tillmann. "These gene probes prove the existence of the toxin-producing algae in seawater samples and they offer an effective future early warning system for mussel farms", Tillmann continues.
Apart from these applied aspects, the researchers are interested in quite fundamental questions: why does the alga produce these azaspiracid toxins and what are their ecological functions? The researchers have already planned the next expedition in order to further pursue these questions - they will head out into the North Sea with RV Heincke at the end of April 2009.
Journal reference:
Urban Tillmann, Malte Elbraumlchter, Bernd Krock, Uwe John, Allan Cembella. Azadinium spinosum gen. et sp. nov. (Dinophyceae) identified as a primary producer of azaspiracid toxins. European Journal of Phycology, 2009; 44 (1): 63 DOI: 10.1080/09670260802578534
Adapted from materials provided by Helmholtz Association of German Research Centres

Dust Deposited In Oceans May Carry Elements Toxic To Marine Algae

Dust Deposited In Oceans May Carry Elements Toxic To Marine Algae.Dust blown off the continents and deposited in the open ocean is an important source of nutrients for marine phytoplankton, the tiny algae that are the foundation of the ocean food web. But new findings show that some sources of dust also carry toxic elements that can kill marine phytoplankton.Researchers discovered the toxic effects during a study of how phytoplankton respond to atmospheric aerosols deposited in the northern Red Sea. The results will be published in the online early edition of the Proceedings of the National Academy of Sciences (PNAS) the week of March 9, 2009."This is the first time that toxicity from atmospheric aerosols has been reported for the ocean system," said first author Adina Paytan, an associate researcher in the Insitute of Marine Sciences at the University of California, Santa Cruz."Oceanographers have always thought of dust deposition as good for phytoplankton, because it provides nutrients such as nitrogen, phosphorus, and iron. But we know air pollution has negative effects on the terrestrial side, and we need to think about the effects of pollutants that may be deposited in the oceans," she said.Paytan and her coworkers collected aerosols on filters, incubated the samples with seawater, and observed the responses of phytoplankton. They found that the results depended on the wind direction. Aerosols collected from air masses originating over Europe stimulated phytoplankton growth, whereas aerosols from air originating over Africa, which carried dust from the Sahara Desert, had the opposite effect.Aerosols from both sources supplied key nutrients such as nitrogen and phosphorus, but the Sahara sources also contained high concentrations of copper. "When we added the Sahara dust, the phytoplankton died within 24 hours," Paytan said. "We found that copper was really high in those samples, so we suspected that copper was causing the toxicity."In follow-up studies, the researchers tested the effects of different concentrations of copper on a dominant species of phytoplankton in the seawater. The organisms (a type of cyanobacterium called Synechococcus) died at the same copper concentrations found in the aerosols. Other studies compared different species of phytoplankton and found variations in their sensitivity to copper."The populations of some organisms crashed, while others breezed right through it. So the effects of copper deposition could change the balance in the ecosystem, allowing less sensitive species to take over," Paytan said.To investigate the global implications of atmospheric copper deposition, the researchers gathered data from various sources on copper concentrations in aerosols, global distributions of aerosols, and aerosol deposition rates. Using an atmospheric deposition model, they calculated rates of copper deposition in different areas of the oceans. They also estimated the contribution of manmade sources of copper compared to pre-industrial rates of copper deposition.Their analysis suggests that manmade sources account for about 40 percent of the copper deposited in the oceans from atmospheric aerosols. Although most of the copper deposition comes from natural sources of dust, the manmade sources are likely to increase over time, Paytan said. In addition, she said, there may be other pollutants in atmospheric aerosols that could also have toxic effects on marine phytoplankton.The modeling study suggested that certain areas--such as the Bay of Bengal and downwind of South and East Asia--are particularly at risk for the effects of copper deposition on ocean ecosystems.The study has several implications for climate change researchers, Paytan said. The amount of dust blowing off the land may change as a result of changes in terrestrial ecosystems. The effects of the dust on phytoplankton growth can be positive or negative, depending on the balance of nutrients and toxins. And as marine phytoplankton grow and photosynthesize, they draw carbon dioxide out of the atmosphere, reducing the atmospheric concentration of the greenhouse gas."There are a lot of questions to follow up on," said Paytan, who has received funding from the National Science Foundation to conduct follow-up studies.In addition to Paytan, the coauthors of the PNAS paper are Katherine Mackey and Ying Chen of UCSC; Ivan Lima and Scott Doney of Woods Hole Oceanographic Institution; Natalie Mahowald of Cornell University; Rochelle Labiosa of the U.S. Geological Survey in Menlo Park; and Anton Post of the Interuniversity Institute of Marine Sciences in Israel.This research was supported in part by grants from NASA, NATO, and the National Science Foundation.

Watershed meeting will seek solution to pollution

The Lemon Bay watershed is under siege. But, Sarasota County officials said, it doesn't have to stay that way. And that will be the goal of an interactive workshop, open to the public and aimed at discussing ways to protect and preserve the quality of the area's creeks and bays. The meeting will be held at 9:30 a.m. to 11:30 a.m. March 21 at the Englewood Sports Complex, 1300 River Road. Sarasota County staff members will lead a discussion with residents about ways they can continue to work together to maintain and improve sea life habitat and water quality in this particular watershed. The watershed workshop is a cooperative effort of Sarasota County and the Southwest Florida Water Management District. The workshop will open with a discussion of the land and water bodies that comprise the Sarasota County portion of the Lemon Bay watershed. The watershed drains into northern Lemon Bay and consists of Alligator Creek, Woodmere Creek, Forked Creek, Gottfried Creek, Ainger Creek and Manasota Key. Project manager Michael Jones said urban development has brought major changes to the watershed over the past half century. "Natural areas were converted to residential, commercial, agricultural and public use," Jones said. "Area residents, builders and developers certainly didn't set out to threaten sea life or water quality." However, he added, "more people and development have placed greater stress on all our natural systems, including the Lemon Bay watershed." Jones said many of the pollution problems in the watershed can be traced to the fact that without the benefit of natural filtration, rainfall streams directly into the bay. That means it is carrying with it pollutants from stormwater runoff. The good news, he said, is that there are opportunities to protect natural systems throughout the watershed through stormwater and landscaping guidelines. "Low-impact design manages rainfall by capturing it on-site," he said. "This approach closely mimics nature by helping to control downstream flooding, reducing water pollution and the imbalance of fresh and saltwater in the estuaries." Sarasota County's landscape and fertilizer management ordinances prescribe appropriate plant materials, as well as fertilizer type and application schedules, he said. For more information about the workshop, call 941-861-5000.

Drilling Could Be Nail In The Coffin For World's Most Endangered Whale Population

"Offshore oil and gas development in Bristol Bay would be the wrong step for the right whale," said Margaret Williams, director of WWF's Bering Sea program. "This is a risk we simply can't afford to take. It would jeopardize the nation's most important fishery, the hundreds of communities that rely on fishing and a treasure trove of wildlife."

bowhead, blue, fin, sei, humpback and sperm whales. A planned lease sale area in Bristol Bay overlaps with critical habitat designated for the eastern North Pacific right.
"Offshore oil and gas development in Bristol Bay would be the wrong step for the right whale," said Margaret Williams, director of WWF's Bering Sea program. "This is a risk we simply can't afford to take. It would jeopardize the nation's most important fishery, the hundreds of communities that rely on fishing and a treasure trove of wildlife."
On January 9, 2007, President Bush rescinded a long-standing presidential moratorium that prohibited drilling in Bristol Bay. In July the new Five Year Oil and Gas Leasing Program of the Minerals Management Service (MMS) - a U.S. government agency - goes into effect and includes plans for a lease sale in Bristol Bay and other areas along the U.S. coastline. Bills to block leasing in Bristol Bay are pending in the House of Representatives and the Senate.
Oil and gas exploration in the Bristol Bay area would expose whales to noise pollution, oil spills, chemical pollution, vessel collisions and entanglement with or ingestion of marine debris. There are no reliable estimates of current abundance or trends for right whales in the North Pacific. According to U.S. government sources, there may be fewer than 300 of these animals left compared to a pre-whaling population of more than 11,000.
Bristol Bay is also the epicenter of the Bering Sea fishery whose commercial salmon, halibut, herring and crab fisheries generate more than $2 billion annually. Sport hunters and fishermen flock to the bay each year, pumping millions of dollars more into the economy. And the region's spectacular wildlife supports scores of Alaskan natives who rely on a healthy ecosystem for food.
"The MMS has calculated average estimates from drilling to generate a total of $7.7 billion, but that's just a fraction of the annual flow of $2 billion from the Bering Sea's renewable and sustainable fishery," said Karen Gillis, executive director of the Bering Sea Fishermen's Association.
Adapted from materials provided by World Wildlife Fund.

Oil, Gas Seismic Work Not Affecting Gulf Sperm Whales, Study Shows

Noise can be irritating and possibly harmful for everything from mice to humans – and maybe even 60-foot whales in the Gulf of Mexico.

In recent years, there has been concern that man-made noise may be a cause of stress for dolphins, whales and other marine mammals, but the results of a five-year study show that noise pollution – especially noise generated by seismic airguns during geophysical exploration for oil and gas – seems to have minimal effect on endangered sperm whales in the Gulf of Mexico, say researchers from Texas A&M University who led the project and released their 323-page report today at the Houston Museum of Natural Science.
The multi-year $9 million study, the largest of its type ever undertaken and formally titled Sperm Whale Seismic Study in the Gulf of Mexico, was conducted by the Minerals Management Service and featured cooperation with the Office of Naval Research, the National Science Foundation and the National Fish and Wildlife Foundation. The project brought together researchers from eight universities, but it was managed overall by Texas A&M's Department of Oceanography, with research scientist Ann Jochens and professor Doug Biggs serving as principal investigators.
"The bottom line is that airgun noise from seismic surveys that are thousands of yards distant does not drive away sperm whales living in the Gulf," Biggs explains.
"However, some individual whales feeding at depth reduced the rate at which they searched acoustically for their prey when scientists carried out controlled exposure experiments by bringing seismic surveys close by the whales. As a result, the oil and gas industry has agreed to a best-practice attitude that seismic surveys should shut down temporarily when towed airguns come within one-third of a mile of whales or groups of whales in the Gulf."
Though not often seen, sperm whales are regular visitors to and residents in the Gulf of Mexico. They are the largest of all toothed whales and can reach lengths of 60 feet or more and live 60 years or longer. Their primary diet is squid and fish and they have been known to dive as deep as 7,000 feet. Humans no longer hunt them for their oil, but the whale in Herman Melville's classic novel Moby Dick was a sperm whale.
Sperm whales are not often seen because they prefer to stay in the deep waters of the Gulf, usually in depths of 3,000 feet or more and at least 150 miles offshore, Biggs says.
"Sperm whales go to where their food source is, and that means very deep water. So folks that do see them are marine mammal observers who ride the seismic survey vessels and the workers on the big oil and gas rigs, and even that does not happen often," Biggs adds.
The primary concern facing the scientific research group was noise – there's more of it in the world's oceans than you might think. A study by the Scripps Institution of Oceanography shows that the world's oceans are 10 times noisier since the 1960s, and at any one time, there are as many as 30,000 ships circling the globe.
Biggs says that over the course of five summers, 98 sperm whales were tagged with devices that relayed back critical data such as measurements about sound levels and behavioral aspects of whales, including tracking their movements. Of particular concern was the effect that loud low-frequency noises, such as those created by seismic activity, might have on sperm whales in the area.
Oil and gas companies prospect for subsea reservoirs by firing air guns during their seismic work, which government regulators thought might negatively affect sperm whale behavior. Also, the sheer volume of work being done in the Gulf was another concern: The Gulf of Mexico accounts for almost 70 percent of the oil and gas extracted from U.S. waters and there are thousands of oil and gas platforms in the region.
But the study found no unusual effects of controlled exposure to seismic exploration on the swimming and diving behavior by sperm whales in the Gulf, and also revealed a wealth of data about sperm whale biology and habitat.
"We now know that the sperm whales in the Gulf appear to be their own distinct stock – they show genetic and social differences from other sperm whales around the world," Biggs says.
"There are believed to be about 500 to 1,500 sperm whales that reside in the Gulf. Most of these are family groups of females and maturing young. When one family group socializes with another family group in the Gulf, they make very distinct sounds. Even though the family groups are visited by males that come into the Gulf from other oceans, their 'clicking' sounds, called codas, the Gulf sperm whales make appear to be different from most others made by sperm whale groups in other parts of the world.
"The five-year study has greatly contributed to our knowledge of sperm whales, especially those found in the Gulf of Mexico. It's also raised new questions we need to know more about, such as their feeding and breeding patterns. There's still a lot we don't know about these huge creatures."
Adapted from materials provided by Texas A&M University

Persistent Man-made Chemical Pollutants Found In Deep-sea Octopods And Squids

New evidence that chemical contaminants are finding their way into the deep-sea food web has been found in deep-sea squids and octopods, including the strange-looking “vampire squid". These species are food for deep-diving toothed whales and other predators.

In a study to be published in the journal Marine Pollution Bulletin, Michael Vecchione of NOAA Fisheries’ National Systematics Laboratory and colleagues Michael Unger, Ellen Harvey and George Vadas at the Virginia Institute of Marine Science of The College of William and Mary report finding a variety of chemical contaminants in nine species of cephalopods, a class of organisms that includes octopods, squids, cuttlefishes and nautiluses.
“It was surprising to find measurable and sometimes high amounts of toxic pollutants in such a deep and remote environment,” Vecchione said. Among the chemicals detected were tributyltin (TBT), polychlorinated biphenyls (PCBs), brominated diphenyl ethers (BDEs), and dichlorodiphenyl-trichloroethane (DDT). They are known as persistent organic pollutants (POPs) because they don't degrade and persist in the environment for a very long time.
Cephalopods are important to the diet of cetaceans, a class of marine mammals which includes whales, dolphins and porpoises. Cephalopods are the primary food for 28 species of odontocetes, the sub-order of cetaceans that have teeth and include beaked, sperm, killer and beluga whales and narwhals as well as dolphins and porpoises.
Recent studies have reported the accumulation of POPs in the blubber and tissues of whales and other predatory marine mammals as well as in some deep-sea fish. Other investigators had speculated that the pollutants in marine mammals had resulted from feeding on contaminated squids. However, almost no information existed prior to this study about POPs in deep-sea cephalopods. Vecchione and colleagues wanted to see if whales had a unique capacity to accumulate pollutants or if they were simply one of the top predators in a contaminated deep-sea food web.
The researchers collected nine species of cephalopods from depths between 1,000 and 2,000 meters (about 3,300 to 6,600 feet) in 2003 in the western North Atlantic Ocean using a large mid-water trawl. Species were selected for chemical analysis based on their importance as prey and included the commercially important short-finned squid Illex illecebrosus, as well as cockatoo squid, “vampire squid”, and the large jelly-like octopus Haliphron atlanticus.
Twenty-two specimens were analyzed for a variety of contaminants. One of the chemical pollutants, TBT, is an additive used to control growth of organisms and is found in antifouling paints for boats, wood preservatives, and many other products. TBT is an endocrine disrupting compound and has been detected in whales and dolphins. It has been regulated worldwide since the late 1980s, but has been a concern because of its extreme toxicity to marine invertebrates in the coastal environment.
Other chemical contaminants found in the specimens include polycyclic aromatic hydrocarbons (PAHs), found in all the samples, diphenyl ether (DPE), polychlorinated biphenyls (PCBs), and brominated diphenyl ethers (BDEs). The researchers also detected DDT, a pesticide banned in the U.S. in the 1970s but still used on a limited basis in some parts of the world to control diseases like malaria.
PCBs are a class of human-produced compounds used to insulate electrical transformers and capacitors and in coatings, sealants, adhesives, paints, wood floor finishes, and even in carbonless copy paper. PCB production was banned in the U.S. in the 1970s. BDEs have been used as flame retardants in a variety of household products, from plastics to foam in furniture and fabrics.
“The cephalopod species we analyzed span a wide range of sizes and represent an important component of the oceanic food web,” Vecchione said. “The fact that we detected a variety of pollutants in specimens collected from more than 3,000 feet deep is evidence that human-produced chemicals are reaching remote areas of the open ocean, accumulating in prey species, and therefore available to higher levels of marine life. Contamination of the deep-sea food web is happening, and it is a real concern.”

Arctic Pollution's Surprising History: Explorers Saw Particulate Haze In Late 1800s

Scientists know that air pollution particles from mid-latitude cities migrate to the Arctic and form an ugly haze, but a new University of Utah study finds surprising evidence that polar explorers saw the same phenomenon as early as 1870।

"The reaction from some colleagues -- when we first mentioned that people had seen haze in the late 1800s -- was that it was crazy," says Tim Garrett, assistant professor of meteorology and senior author of the study. "Who would have thought the Arctic could be so polluted back then? Our instinctive reaction is to believe the world was a cleaner place 130 years ago."
By searching through historic records written by early Arctic explorers, Garrett and his collaborator Lisa Verzella, former undergraduate student at the University of Utah, were able to find evidence of an aerosol "dry haze" that settled onto the ice to form a layer of grayish dust containing metallic particles. The haze and dust were likely the byproducts of smelting and coal combustion generated during the Industrial Revolution.
"We searched through open literature, including a report in the second issue of the journal Science in 1883 by the famous Swedish geologist Adolf Erik Nordenskiold, who was the first to describe the haze," says Garrett. "We also looked through books describing Arctic expeditions that had to be translated from Norwegian and French."
The historic accounts show that more than 130 years ago, the Industrial Revolution was "already darkening the snow and skies of the far North," Garrett says.
History of Arctic Pollution
Garrett and Verzella say the first report of Arctic haze pollution usually is credited to a U.S. Air Force meteorologist J. Murray Mitchell, who in 1957 described "the high incidence of haze at flight altitudes" during weather reconnaissance missions from Alaska over the Arctic Ocean during the late 1940s and 1950s.
Mitchell was credited in the 1970s by Glenn Shaw from the University of Alaska, Fairbanks, and his collaborators Kenneth Rahn and Randolf Borys, from the University of Rhode Island, who were the first to discover the haze contained high levels of heavy metals, including vanadium, suggestive of heavy oil combustion.
In a later study, Rahn and Shaw said: "Arctic haze is the end product of massive transport of air pollution from various mid-latitude sources to the northern polar regions, on a scale that could never have been imagined, even by the most pessimistic observer."
Since humans had been generating aerosol pollution long before 1950 -- namely, since sometime after the advent of the Industrial Revolution in the late 1700s -- it made sense to Garrett that pollution generated from earlier times also might have made it to northern latitudes from Europe, Asia and North America.
"I thought that pollution had to be observed in the Arctic prior to 1950, so I decided to find out if that was true," says Garrett. So he hired Verzella to search historic records to determine if there was written evidence of early Arctic pollution.
Verzella found a number of published reports from the late 1800s to early 1900s that mention a whitish haze in the sky, or a gray or black dust on the ice. But Nordenskiold "was the first to explicitly draw attention to the haze phenomenon" during his 1883 expedition to Greenland, the researchers concluded.
Even during an earlier expedition in 1870, Nordenskiold observed "a fine dust, gray in color, and, when wet, black or dark brown, is distributed over the inland ice in a layer which I should estimate at from 0.1 to 1 millimeter."
He found that the dust contained "metallic iron, which could be drawn out by the magnet, and which, under the blowpipe, gave a reaction of cobalt and nickel." He believed it to be a "cosmic dust" possibly from meteors. However, the concentration of metallic iron, nickel and cobalt made it much more likely that the origin was industrial pollution generated at mid-latitudes.
Last year, other researchers found that the dust is present in ice core samples. "Recent Greenland ice cores show a rapid rise in anthropogenic soot and sulfate that began in the late 1800s, but with peak sulfate levels in the 1970s, and peak soot between 1906 and 1910," Garrett and Verzella say in their study. A higher composition of sulfate suggests oil combustion, while higher soot suggests coal combustion, consistent with the main sources of pollution generated in the 20th versus 19th centuries.
Early Arctic Warming
In a 2006 study, Garrett concluded that particulate pollution from mid-latitudes aggravates global warming in the Arctic. Did it do the same back in the 1800s?
"It is reasonable that the effect of particulate pollution on Arctic climate may have been greater 130 years ago than it is now, because during the Industrial Revolution, technologies were dirtier than they are now," says Garrett. "Of course, today carbon dioxide emissions are greater and have accumulated over the last century, so the warming effect due to carbon dioxide is much greater today than 100 years ago."
In fact, after fossil-fuel combustion became more efficient in the mid-1900s, the levels of particulate pollution in the Arctic dropped dramatically from levels earlier in the century. However, Garrett believes that we might be seeing another increase due to higher emissions from developing industrial countries such as China.
The study will be published in the March 2008 issue of the Bulletin of the American Meteorological Society.
Adapted from materials provided by University of Utah.