Surfers can't resist the thundering waves in an old city canal in the heart of Germany, writes Manuel Mitternacht.
IT'S a surfer's dream. A ride that never ends, even though it's hundreds of kilometres from the nearest ocean beach.
In the heart of a historic German city, a unique, standing wave attracts hundreds of board riders and thousands of onlookers every year. The 12-metre-wide permanent break is fed by the waters of the Eisbach - a canal that runs through Munich's famous Englischer Garten city park.
Now bureaucratic red tape threatens to stop the popular phenomenon that began more than 30 years ago.
The name Eisbach literally means "ice stream".
Water temperatures can plunge to four degrees in Bavarian winters. The steady curl, sandwiched between two concrete banks, emerges from the rapids when the Eisbach thunders through arched tunnels under a bridge and strikes three submerged concrete blocks at 36kmh.
Its speed allows surfers to trim backward and forwards - executing radical slides, cut-backs and re-entries, even 360-degree turns.
Local surfers have wedged wooden boards into the canal's bed to help force more water into the wave and make the ride even more challenging. "It's only two to three feet high, but the fast flow gives it the punch of a six-foot ocean wave," said Bjoern Richie Lob.
The 33-year-old filmmaker from Cologne moved to Munich because of the Eisbach wave.
"A friend showed me the wave - one could say it was love at first sight," he said.
On another part of the city's waterways, on the Isar River, a smaller and gentler wave - the Flosslaende - has been the sight of the Munich Surf Open sponsored by Australian-founded company Quiksilver.
Mr Lob is producing a surf-movie about the Eisbach.
Seven-times Australian surfing world champion Layne Beachly told him in an interview for the film that the break could become an inspiration for professional surfing.
"Because surfing out in the ocean is so far away, we feel so isolated from people," Beachley said.
"The river makes surfing a lot more tangible. People can come and surround it and create an arena-type environment and I think this is what surfing lacks."
On the 19th-century arched stone Prinzregentenstrasse bridge, next to the city's modern-art museum, hordes of amazed tourists cheer the riders below while locals make well-informed comments about the performance.
As soon as a surfer wipes out, the next one throws his board into the foaming water.
Experienced riders can surf the wave for minutes while rookies last only a few seconds before they are swallowed by the gushing waters.
Professional photographer and Eisbach surfer Florian Hagena knows the surf etiquette at the break well. "In theory you could ride the wave forever, but after about 45 seconds the guys in the line-up get a bit nervous, and it's time to drop out."
Even when snow covers the river banks they line up to surf the wave.
A handful of hardcore riders show even more commitment to their addiction.
To have the wave just for themselves, they come at night with power generators and floodlights for nocturnal surfing sessions.
Although it is not legal to swim or surf in the Eisbach, Munich's city council had a history of tolerance for the surfers and used them for promotion on its official webpage to show the town's cooler, groovier side.
But to escape public liability costs, authorities plastered the bridge and the surrounding shore with signs banning surfing. However, the ban has never been enforced by police or park rangers.
This was in line with Munich's laissez-faire approach to its famous nude sun-bathers - the so-called "Nackerten" - who line the shores of the Eisbach in the Englischer Garten (English Garden) a few hundred metres down stream.
But the English Garden is administered by the Bavarian State, not by the city, and park manager Thomas Koester has a different position towards this form of "anarchy".
Mr Koester calls for law and order in his park.
"We need a touch of Singapore in the English Garden," he told the German paper Sueddeutsche Zeitung.
The tragic death of a 27-year-old Sydney tourist who drowned in the Eisbach last July strengthened the authoritarian approach.
He disappeared in the Eisbach while swimming in the lower part of the English Garden.
His body was caught in an underwater eddy for three days before the creek released it. Although the death was not related to the wave under the bridge, the city council became nervous.
In summer, tourists and locals take a dip in Eisbach after sunbathing or a visit to the nearby beer garden. But the treacherous undertows and underwater currents that occur about one kilometre downstream from the break have claimed eight lives in the past 10 years.
Suddenly pictures of the surfers were removed from the council's homepage and rumours about the demolition of the wave by the Bavarian state authorities appeared in a local newspaper.
Recently, the Bavarian State Parliament tightened the legislation and announced that police will enforce the ban.
This sent shock waves through the Bavarian surfing fraternity. Supporters of the surf movement set up a webpage where more than 10,000 people signed a petition to keep the wave rolling.
Despite a truce with authorities, the issue is not resolved and there is an awkward stand-off between authorities and surfers.
Guido Bernhard and Nico Meisner founded Buster Surfboards in 2002 to create surfboards especially for Eisbach conditions.
Their "E-Type" board's foam cores are imported from Brookvale on Sydney's northern beaches.
Last year's Munich Surf Open winner, 24-year-old snow board instructor, Laura Sonntag is a second generation Eisbach surfer.
More than a third of this year's Open entries were women. Layne Beachly would be proud.
Professional photographer and Eisbach surfer Florian Hagena knows the surf etiquette at the break well. "In theory you could ride the wave forever, but after about 45 seconds the guys in the line-up get a bit nervous, and it's time to drop out."
Even when snow covers the river banks they line up to surf the wave.
A handful of hardcore riders show even more commitment to their addiction.
To have the wave just for themselves, they come at night with power generators and floodlights for nocturnal surfing sessions.
Although it is not legal to swim or surf in the Eisbach, Munich's city council had a history of tolerance for the surfers and used them for promotion on its official webpage to show the town's cooler, groovier side.
But to escape public liability costs, authorities plastered the bridge and the surrounding shore with signs banning surfing. However, the ban has never been enforced by police or park rangers.
This was in line with Munich's laissez-faire approach to its famous nude sun-bathers - the so-called "Nackerten" - who line the shores of the Eisbach in the Englischer Garten (English Garden) a few hundred metres down stream.
But the English Garden is administered by the Bavarian State, not by the city, and park manager Thomas Koester has a different position towards this form of "anarchy".
Mr Koester calls for law and order in his park.
"We need a touch of Singapore in the English Garden," he told the German paper Sueddeutsche Zeitung.
The tragic death of a 27-year-old Sydney tourist who drowned in the Eisbach last July strengthened the authoritarian approach.
He disappeared in the Eisbach while swimming in the lower part of the English Garden.
His body was caught in an underwater eddy for three days before the creek released it. Although the death was not related to the wave under the bridge, the city council became nervous.
In summer, tourists and locals take a dip in Eisbach after sunbathing or a visit to the nearby beer garden. But the treacherous undertows and underwater currents that occur about one kilometre downstream from the break have claimed eight lives in the past 10 years.
Suddenly pictures of the surfers were removed from the council's homepage and rumours about the demolition of the wave by the Bavarian state authorities appeared in a local newspaper.
Recently, the Bavarian State Parliament tightened the legislation and announced that police will enforce the ban.
This sent shock waves through the Bavarian surfing fraternity. Supporters of the surf movement set up a webpage where more than 10,000 people signed a petition to keep the wave rolling.
Despite a truce with authorities, the issue is not resolved and there is an awkward stand-off between authorities and surfers.
Guido Bernhard and Nico Meisner founded Buster Surfboards in 2002 to create surfboards especially for Eisbach conditions.
Their "E-Type" board's foam cores are imported from Brookvale on Sydney's northern beaches.
Last year's Munich Surf Open winner, 24-year-old snow board instructor, Laura Sonntag is a second generation Eisbach surfer.
More than a third of this year's Open entries were women. Layne Beachly would be proud.
Tuesday, October 28, 2008
Oregon Coast 'dead zone' comes back to life
By KEELEY CHALMERS / KGW.com
PORTLAND - Two years ago scientists made a shocking discovery just off the Oregon Coast. They found a area referred to as a dead zone.
Underwater video showed shocking images of dead crabs and fish. Marine animal carcasses littered the ocean floor. A once breathtaking reef had turned into an underwater graveyard.
Oregon's dead zone had reached record proportions. The water was totally oxygen depleted.
“In 2006 it actually hit bottom we had zero oxygen values,” explained Dr. Francis Chan, a Zoology Researcher at OSU.
Chan studied the dead zone back in 2006 and has been ever since. Said Chan, “We’ve been keeping a really close eye on what oxygen levels.”
Chan and his research team recently returned to the dead zone to answer the looming question: had it come back to life?
Underwater video taken by the Oregon Department of Fish and Wildlife showed the area had started to come back to life, or at least some of it had.
“Things seem to be moving back into an area that was basically void of this large marine life,” said Chan.
But because oxygen levels are still low, Chan says recovery is happening painfully slow and not all creatures are bouncing back. Chan says the once abundant sea cucumber hasn’t been seen in the system since 2006.
The dead zone sits less than a mile off the Oregon coast between Newport and Florence. And Chan says new research shows another dead zone has emerged off the Washington coast. The low oxygen areas are the result, he believes, of global warming.
“When you warn the surface ocean you tend to decrease the amount of oxygen you have,” said Chan.
Which leaves scientists to wonder, as our climate continues to change, will our ocean ever be able to fully recover?
Chan says that’s a hard question to answer, but he and his fellow researchers plan to head back out to sea to try.
PORTLAND - Two years ago scientists made a shocking discovery just off the Oregon Coast. They found a area referred to as a dead zone.
Underwater video showed shocking images of dead crabs and fish. Marine animal carcasses littered the ocean floor. A once breathtaking reef had turned into an underwater graveyard.
Oregon's dead zone had reached record proportions. The water was totally oxygen depleted.
“In 2006 it actually hit bottom we had zero oxygen values,” explained Dr. Francis Chan, a Zoology Researcher at OSU.
Chan studied the dead zone back in 2006 and has been ever since. Said Chan, “We’ve been keeping a really close eye on what oxygen levels.”
Chan and his research team recently returned to the dead zone to answer the looming question: had it come back to life?
Underwater video taken by the Oregon Department of Fish and Wildlife showed the area had started to come back to life, or at least some of it had.
“Things seem to be moving back into an area that was basically void of this large marine life,” said Chan.
But because oxygen levels are still low, Chan says recovery is happening painfully slow and not all creatures are bouncing back. Chan says the once abundant sea cucumber hasn’t been seen in the system since 2006.
The dead zone sits less than a mile off the Oregon coast between Newport and Florence. And Chan says new research shows another dead zone has emerged off the Washington coast. The low oxygen areas are the result, he believes, of global warming.
“When you warn the surface ocean you tend to decrease the amount of oxygen you have,” said Chan.
Which leaves scientists to wonder, as our climate continues to change, will our ocean ever be able to fully recover?
Chan says that’s a hard question to answer, but he and his fellow researchers plan to head back out to sea to try.
NOAA And NSF Commissions Study Of Ocean Acidification's Impact On U.S. Waters
Underwatertimes.com News ServiceOctober 22, 2008 19:53 EST
Washington, D.C. -- The first comprehensive national study of how carbon dioxide emissions absorbed into the oceans may be altering fisheries, marine mammals, coral reefs, and other natural resources has been commissioned by NOAA and the National Science Foundation.
"Carbon dioxide released into the atmosphere through the burning of fossil fuels is not only contributing to atmospheric climate change," said Dr. Steven A. Murawski, director of scientific programs and chief science advisor for NOAA's Fisheries Service. "These emissions are being absorbed into the oceans with potentially catastrophic effects on life in our oceans. Some of the most vulnerable species – clams, crabs, lobsters, mussels, shrimp, and scallops -are also some of the most important economically to the United States, representing half of the $4 billion annual value of all fish harvested in U.S. waters."
The need for this national study, to be conducted by the National Academy of Sciences, was outlined by Congress in the reauthorization of the Magnuson-Stevens Fishery Conservation and Management Act in 2007.
Since the beginning of the industrial era, the oceans have absorbed about a third of all manmade carbon dioxide emissions released into the air. The ability of the oceans to absorb carbon dioxide emissions has reduced some of the harmful effects of heat-trapping greenhouse gases in the atmosphere and on land. But scientists are finding that the continued, increased absorption of these gases is altering the biology and chemistry of oceans in fundamental ways.
Absorption of large amounts of carbon dioxide alters the chemistry of the oceans by reducing the pH of seawater. With increasing carbon dioxide in seawater, shellfish and corals cannot absorb enough calcium carbonate to build strong skeletons and shells. The greater acidity slows the growth and even dissolves ocean plant and animal shells. The decline of these valuable species would drastically harm U.S. fisheries.
Any decline of these species would also have profound effects on entire ecosystems where shellfish and crustaceans provide food for many other species and coral provides habitat for fish. The effects of ocean acidification will potentially extend to coral reefs, marine plankton, other animals and plants.
The National Research Council of the National Academy of Sciences is putting together a panel of 10 to 12 scientists to undertake the 18-month study. The committee will be made up of scientists with expertise in chemical oceanography, paleooceanography, biological oceanography, physiology, marine ecology, resource economics, geochemistry, resource management, and ocean-climate modeling.
Washington, D.C. -- The first comprehensive national study of how carbon dioxide emissions absorbed into the oceans may be altering fisheries, marine mammals, coral reefs, and other natural resources has been commissioned by NOAA and the National Science Foundation.
"Carbon dioxide released into the atmosphere through the burning of fossil fuels is not only contributing to atmospheric climate change," said Dr. Steven A. Murawski, director of scientific programs and chief science advisor for NOAA's Fisheries Service. "These emissions are being absorbed into the oceans with potentially catastrophic effects on life in our oceans. Some of the most vulnerable species – clams, crabs, lobsters, mussels, shrimp, and scallops -are also some of the most important economically to the United States, representing half of the $4 billion annual value of all fish harvested in U.S. waters."
The need for this national study, to be conducted by the National Academy of Sciences, was outlined by Congress in the reauthorization of the Magnuson-Stevens Fishery Conservation and Management Act in 2007.
Since the beginning of the industrial era, the oceans have absorbed about a third of all manmade carbon dioxide emissions released into the air. The ability of the oceans to absorb carbon dioxide emissions has reduced some of the harmful effects of heat-trapping greenhouse gases in the atmosphere and on land. But scientists are finding that the continued, increased absorption of these gases is altering the biology and chemistry of oceans in fundamental ways.
Absorption of large amounts of carbon dioxide alters the chemistry of the oceans by reducing the pH of seawater. With increasing carbon dioxide in seawater, shellfish and corals cannot absorb enough calcium carbonate to build strong skeletons and shells. The greater acidity slows the growth and even dissolves ocean plant and animal shells. The decline of these valuable species would drastically harm U.S. fisheries.
Any decline of these species would also have profound effects on entire ecosystems where shellfish and crustaceans provide food for many other species and coral provides habitat for fish. The effects of ocean acidification will potentially extend to coral reefs, marine plankton, other animals and plants.
The National Research Council of the National Academy of Sciences is putting together a panel of 10 to 12 scientists to undertake the 18-month study. The committee will be made up of scientists with expertise in chemical oceanography, paleooceanography, biological oceanography, physiology, marine ecology, resource economics, geochemistry, resource management, and ocean-climate modeling.
The beauty of Waves
we were talking about waves the other day in class, so i thought i would post a few pictures from one of my favorite photographers aaron chang. Within these photos you can see the power, beauty and form that has been captured. enjoy:)
Tuesday, October 14, 2008
The Oceans
Ocean circulation
Energy from the Sun doesn't fall equally all over the Earth. Most of the Sun's energy enters the Earth at the equator. This leads to large temperature gradients between the equator and the Poles. Movement of both the air and the oceans is controlled by these temperature differences and the result is a transfer of heat from the equator to the poles. About half the heat transport around the planet is by the oceans so the oceans are an extremely important part of the Earth's climate control system. If ocean circulation is changed by global warming, major changes in climate are therefore likely. Ocean circulation also transports oxygen from the air into the ocean making marine life possible.
Seawater continuously moves around the globe as if it is on a huge conveyor belt, moving from the surface to the deep waters and back. Because the distance the water has to travel is so large, it takes about 1000 years for seawater to go all the way around the Earth.
The movement of water around the oceans has two parts which are strongly linked:
1) a density driven circulation which is driven by the differences in the density of seawater at different locations. The density of seawater depends on its temperature and how salty it is. As a result, this movement is known as the thermohaline circulation (Greek: thermo = heat, háls = salt).
2) a wind driven circulation which results in huge surface currents like the Gulf Stream.
SEE PICTURE UP ABOVE
Thermohaline circulation
In the Northern Hemisphere
Ocean circulation transports surface seawater to the polar region where it cools. This cooling releases heat which warms the air and makes the water cold and, therefore, dense enough to sink to the bottom of the ocean. This results in the formation of new deep water which displaces existing deep water pushing it towards the equator. The major regions for this deep water formation are the Labrador and Greenland Seas in the northern North Atlantic Ocean. This North Atlantic Deep Water then flows south along the ocean floor allowing more warm surface water to flow into the region to replace it. Strong cooling also occurs in the Bering Sea in the North Pacific, but the structure of the ocean floor here prevents the deep water that forms from entering the ocean circulation.
Antarctica
Deep water formation also occurs around Antarctica during the production of sea ice. This ice contains very little salt and so, as the ice forms, the surrounding water becomes saltier and more dense. This very dense water slides down the edge of the Antarctic continent to form Antarctic Bottom Water. This water then spreads out and moves around most of the ocean floor.
For some time we thought that the deep waters that formed at the poles moved towards the equator, slowly warming and rising to the surface over the whole ocean, and that this water then returned to the poles in warm surface currents to complete the cycle. However, recent studies have shown that this gradual upwelling process is too slow to explain the age of seawater.
We now think that as deep water circulates around the bottom of the ocean, it meets the mid ocean ridges which are mountainous areas on the sea floor. The roughness of these causes strong mixing which forces the deep water to rise to the surface. The wind also causes strong mixing in the Southern Ocean and this also brings the deep water back to the surface. Once at the surface, the water returns to the poles in wind driven surface currents to complete its cycle.
Wind driven circulation
The Gulf Stream
The Gulf Stream is one of the most important wind driven currents. It transports very warm tropical water from the Caribbean Sea and the Gulf of Mexico across the North Atlantic to northern Europe. The warmth of the water heats the air above and the movement of this warm air is a very important way by which heat is transported northwards. As a result of this heat transport, northern Europe is very much warmer than corresponding latitudes in North America and countries around the Pacific Ocean.
3. This image clearly shows the warm waters of the Gulf Stream (in red) travelling across the North Atlantic. You can just about see the coastline of North America in the left hand corner. It was taken by MODIS (the Moderate Resolution Imaging Spectroradiometer) aboard the NASA Terra and Aqua satellites. Click on the image to get a better view (63 KB).
For example, the yearly average temperature at Iqaluit (64oN, 068oW) in the Northwest Territories of Canada is -9.1 oC. This compares with an average for Trondheim (63oN, 010oE) in Norway of +4.8 oC. Long term records suggest that, as a result of the Gulf Stream, average temperatures in Northern Europe are 9 oC higher than the average temperatures for the same latitude elsewhere.
The Gulf Stream is an example of a western boundary current, a current which flows along the western side of a major ocean basin. The corresponding current in the Pacific Ocean is the Kuroshio Current, and in the Indian Ocean, the Aghulas Current. They result from an interaction between the shape of the ocean basin, the general direction of the wind and the rotation of the earth. They all have a high velocity (the Gulf Stream has an average velocity of 1 m s-1, thats 3.6 km h-1) they are all quite narrow (between 100 and 200 km wide) and all have a very important influence on the climate of the region. Eastern boundary currents also occur; these transport cold surface waters from the poles to the equator. They tend to be weaker than their western counterparts.
About this page:
author: Dr. Lucinda Spokes - Environmental Sciences, University of East Anglia, Norwich - U.K.scientific reviewer: Prof. Grant Bigg - Department of Geography, University of Sheffield, Sheffield - U.K.educational reviewers: Francis Mudge - School of Education and Professional Development, University of East Anglia, Norwich - U.K. and Trevor Leggett - Chemistry Teacher, Norwich - U.K.check and last update: 2008-04-14
Monday, October 13, 2008
Sixty-nine Nations Adopt Guidelines To Protect Fish Species; 'A Breakthrough'
Underwatertimes.com News ServiceSeptember 3, 2008 18:36 EST
New York, New York -- Two years of negotiations have resulted in the adoption of new international guidelines to limit the impact of fishing on fragile deep sea fish species and habitats, the United Nations Food and Agriculture Organization (FAO) announced today.
picture:
(Deep sea fish species like the morid cod have low resilience to intensive fishing )
(Deep sea fish species like the morid cod have low resilience to intensive fishing )
Managing deep sea fisheries in high seas areas
outside of countries’ exclusive economic zones has always been difficult, according to FAO, since it requires multilateral solutions involving not only nations whose vessels are engaged in deep sea fisheries but other interested countries as well.
“Until now, there really hasn’t been an international framework for tackling this issue,” said Ichiro Nomura, Assistant Director General of FAO’s Department of Fisheries and Aquaculture.
“These guidelines represent one of the few practical instruments of this nature, and are a breakthrough in that they address both environmental and fisheries management concerns in an integrated manner,” he added.
Stating that all fishing activity in deep sea areas should be “rigorously managed,” the guidelines contain measures to be taken to identify and protect vulnerable ecosystems and provide guidance on the sustainable use of marine living resources in deep-sea areas.
They also recommend that fishing nations assess the deep sea fishing being undertaken by their fleets to determine if any significant adverse impacts are involved, and if there are adverse impacts, the fishing activity should stop.
The guidelines also set out steps for improving information on the location and status of vulnerable marine ecosystems and deep sea fisheries.
Because deep sea fishing is a relatively new activity and requires considerable resources in terms of investment and technology, few countries have so far developed policies and plans specifically related to managing it, even in their own waters, according to FAO.
“These guidelines represent one of the few practical instruments of this nature, and are a breakthrough in that they address both environmental and fisheries management concerns in an integrated manner,” he added.
Stating that all fishing activity in deep sea areas should be “rigorously managed,” the guidelines contain measures to be taken to identify and protect vulnerable ecosystems and provide guidance on the sustainable use of marine living resources in deep-sea areas.
They also recommend that fishing nations assess the deep sea fishing being undertaken by their fleets to determine if any significant adverse impacts are involved, and if there are adverse impacts, the fishing activity should stop.
The guidelines also set out steps for improving information on the location and status of vulnerable marine ecosystems and deep sea fisheries.
Because deep sea fishing is a relatively new activity and requires considerable resources in terms of investment and technology, few countries have so far developed policies and plans specifically related to managing it, even in their own waters, according to FAO.
Mexico tourism boom kills coral quicker than climate change
Published Date: 05 October 2008
By Jason Lange in Cancun, Mexico
DAINTY blue fish still dart around coral shaped like antlers near the Mexican resort of Cancun, but pollution is threatening one of the world's largest reefs.
Parts of the reef, nestled in turquoise waters, have died, and algae – which feed on sewage residues flowing out of the fast-growing hotels in the tourist city – has taken over.
Coral in areas such as Chitales, near the northern tip of a Caribbean reef chain stretching from Mexico to Honduras, are dying as people and cities put more stress on the environment.Climate change alone could trigger a global coral extinction by 2100 because carbon emissions warm oceans and make them more acidic, according to a recent study.But local environmental problems, such as sewage, farm run-off and over-fishing, could kill much of the world's reefs decades before global warming does, said Roberto Iglesias, a biologist from Unam university's marine sciences station near Cancun."The net effect of pollution is as bad or maybe worse than the effects of global warming," said Iglesias, a co-author of the study in the journal Science.Human waste, like that from Cancun's hotels and night spots, aggravates threats to coral worldwide, such as overzealous fishing, which hurts stocks of fish that eat reef-damaging algae. Coral reefs are covered with tiny animals called coral polyps, which build the reefs by slowly secreting calcium carbonate over thousands of years, creating structures that can dull the blow hurricanes deal to coastal cities. The polyps also give the reefs their dazzling shades of pink and purple.Across the Caribbean, the amount of reef surface covered by live coral has fallen about 80% in the past 30 years, the Global Coral Reef Monitoring Network says.In the Pacific, between Hawaii and Indonesia, reefs have been losing about 1% of their coral coverage annually over the past 25 years.It is hard to tell how much of that damage was caused by global warming and how much by local factors such as pollution.Some scuba diving instructors around Cancun are worried about the future of their trade. Jorge Olivieri, who has been taking tourists out diving in the area for the past 16 years, says some reefs are so damaged he would not take an experienced diver to see them. "There are still fish and coral, but it isn't like it used to be," he said.Fixing problems like poor sewage treatment and over-fishing are among the few things that countries and cities can do to help their reefs."The local factors are the only things we can manage at this point and they are absolutely critical," said Drew Harvell, a biologist at Cornell University.In the late 1960s, Cancun was barely inhabited.Then Mexican bureaucrats, hungry for foreign currency and armed with statistics on sunshine, hatched a plan to turn the area into a tourist area. Today millions of people each year pack into hotels running the length of the strip.
By Jason Lange in Cancun, Mexico
DAINTY blue fish still dart around coral shaped like antlers near the Mexican resort of Cancun, but pollution is threatening one of the world's largest reefs.
Parts of the reef, nestled in turquoise waters, have died, and algae – which feed on sewage residues flowing out of the fast-growing hotels in the tourist city – has taken over.
Coral in areas such as Chitales, near the northern tip of a Caribbean reef chain stretching from Mexico to Honduras, are dying as people and cities put more stress on the environment.Climate change alone could trigger a global coral extinction by 2100 because carbon emissions warm oceans and make them more acidic, according to a recent study.But local environmental problems, such as sewage, farm run-off and over-fishing, could kill much of the world's reefs decades before global warming does, said Roberto Iglesias, a biologist from Unam university's marine sciences station near Cancun."The net effect of pollution is as bad or maybe worse than the effects of global warming," said Iglesias, a co-author of the study in the journal Science.Human waste, like that from Cancun's hotels and night spots, aggravates threats to coral worldwide, such as overzealous fishing, which hurts stocks of fish that eat reef-damaging algae. Coral reefs are covered with tiny animals called coral polyps, which build the reefs by slowly secreting calcium carbonate over thousands of years, creating structures that can dull the blow hurricanes deal to coastal cities. The polyps also give the reefs their dazzling shades of pink and purple.Across the Caribbean, the amount of reef surface covered by live coral has fallen about 80% in the past 30 years, the Global Coral Reef Monitoring Network says.In the Pacific, between Hawaii and Indonesia, reefs have been losing about 1% of their coral coverage annually over the past 25 years.It is hard to tell how much of that damage was caused by global warming and how much by local factors such as pollution.Some scuba diving instructors around Cancun are worried about the future of their trade. Jorge Olivieri, who has been taking tourists out diving in the area for the past 16 years, says some reefs are so damaged he would not take an experienced diver to see them. "There are still fish and coral, but it isn't like it used to be," he said.Fixing problems like poor sewage treatment and over-fishing are among the few things that countries and cities can do to help their reefs."The local factors are the only things we can manage at this point and they are absolutely critical," said Drew Harvell, a biologist at Cornell University.In the late 1960s, Cancun was barely inhabited.Then Mexican bureaucrats, hungry for foreign currency and armed with statistics on sunshine, hatched a plan to turn the area into a tourist area. Today millions of people each year pack into hotels running the length of the strip.
Ocean Conservationists Laud President Bush's Proposal To Protect Vast Pacific Coral Reef Areas
Underwatertimes.com News ServiceAugust 25, 2008 18:02 EST
Washinton, D.C. -- Prominent ocean conservationists are encouraged by President Bush's announcement today directing his Administration to consider protecting a number of very large, ecologically important ocean areas. However, they are concerned that the proposal could allow for multiple-use practices that would harm the species and ecosystems in these areas. The sites are remote reef-cloaked US possessions and their surrounding waters in the Central Pacific, and the world's smallest atoll in American Samoa.
Marine Conservation Biology Institute (MCBI) and Environmental Defense Fund (EDF) have worked together for nearly two years to encourage the Bush Administration to protect these areas from industrial fishing and other threats to ocean life.
"People everywhere should praise this visionary idea," said Marine Conservation Biology Institute Board member Dr. Sylvia A. Earle, "if President Bush does what no world leader has ever done before: fully protect these colossal areas of shallow and deep coral reefs, seamounts and other vulnerable marine ecosystems in the Pacific Ocean, now and forever," she said.
Dr. Earle, perhaps the world's most famous ocean explorer, served as Chief Scientist of the National Oceanic and Atmospheric Administration under President George H.W. Bush. She is also Chairman of Deep Ocean Exploration and Research and Explorer-in-Residence at the National Geographic Society.
"Two years ago, President Bush shook the world when he made the Northwestern Hawaiian Islands a Marine National Monument and what was then the world's largest no-take marine reserve," said MCBI Board member James C. Greenwood. "He gifted Americans and the world by protecting life in an incredible area of ocean 1,200 miles long and 100 miles wide," said The Honorable Mr. Greenwood, a Republican who served six terms as a US Representative from Pennsylvania and was a founder of the House Oceans Caucus before leaving Congress and becoming President of the Biotechnology Industry Organization.
"If the President ultimately acts to protect these amazing areas of ocean to the fullest extent," said Mr. Greenwood, "his conservation legacy will rival that of President Teddy Roosevelt. Leadership in protecting our planet can and must come from Republicans and Democrats alike," he continued. "The fate of our oceans is far more important than partisan politics."
Large fish species, corals and vulnerable marine ecosystems are disappearing around the world. In the last several decades, 90% of big fishes including bluefin tunas, blue marlin and large groupers, have been wiped out. A growing number of marine scientists around the world believe that fully protected no-take marine reserves are the most powerful way to counter these losses.
Dr. Earle, Mr. Greenwood, and MCBI and EDF staff members met repeatedly with high-level Bush Administration officials, encouraging them to safeguard the waters surrounding various Central Pacific islands and Rose Atoll in American Samoa, among other sites.
"The President's announcement is highly encouraging," said William J. Chandler, Vice President for Government Affairs at Marine Conservation Biology Institute. "By using his presidential powers under the Antiquities Act and other statutes to fully protect ocean areas like he did in Hawaii, President Bush could write a new chapter in the history of conservation."
"This could be the best thing ever for ocean conservation. These vast Pacific areas are nearly three times the size of Texas," said Dr. Elliott A. Norse, founder and President of Marine Conservation Biology Institute. "Indeed, they're bigger than Mexico. Countless seabirds, dolphins, fishes, corals and tiny things as yet undiscovered could survive as a result, free of the threats that are eliminating them elsewhere, if the President gives full protection to these areas. I am thrilled that President Bush is considering this," said Dr. Norse.
The world's coral reefs and coral species are in trouble. The National Oceanic and Atmospheric Administration recently reported that nearly half of US coral reefs are in poor to fair condition. And a large group of international scientists recently reported that one-third of reef-building corals face elevated extinction risk from climate change and local impacts. The areas being considered are coral islands, atolls and reefs that are US territories and possessions in the Central Pacific Ocean, including Baker, Howland, Jarvis, Johnston, Kingman, Palmyra, Wake and Rose. Dr. Earle, Dr. Norse and 192 other American marine scientists recently called upon President Bush to give strong permanent protection to these reefs and their surroundings. The Governor of American Samoa, Togiola T.A. Tulafono has requested the President designate Rose Atoll in American Samoa as a national monument.
Marine Conservation Biology Institute is a nonprofit organization dedicated to advancing the science of marine conservation biology and securing protection for the world's marine ecosystems. Founded in 1996, MCBI is headquartered in Bellevue, WA, and has offices in Honolulu, HI, Glen Ellen, CA and Washington, DC.
Washinton, D.C. -- Prominent ocean conservationists are encouraged by President Bush's announcement today directing his Administration to consider protecting a number of very large, ecologically important ocean areas. However, they are concerned that the proposal could allow for multiple-use practices that would harm the species and ecosystems in these areas. The sites are remote reef-cloaked US possessions and their surrounding waters in the Central Pacific, and the world's smallest atoll in American Samoa.
Marine Conservation Biology Institute (MCBI) and Environmental Defense Fund (EDF) have worked together for nearly two years to encourage the Bush Administration to protect these areas from industrial fishing and other threats to ocean life.
"People everywhere should praise this visionary idea," said Marine Conservation Biology Institute Board member Dr. Sylvia A. Earle, "if President Bush does what no world leader has ever done before: fully protect these colossal areas of shallow and deep coral reefs, seamounts and other vulnerable marine ecosystems in the Pacific Ocean, now and forever," she said.
Dr. Earle, perhaps the world's most famous ocean explorer, served as Chief Scientist of the National Oceanic and Atmospheric Administration under President George H.W. Bush. She is also Chairman of Deep Ocean Exploration and Research and Explorer-in-Residence at the National Geographic Society.
"Two years ago, President Bush shook the world when he made the Northwestern Hawaiian Islands a Marine National Monument and what was then the world's largest no-take marine reserve," said MCBI Board member James C. Greenwood. "He gifted Americans and the world by protecting life in an incredible area of ocean 1,200 miles long and 100 miles wide," said The Honorable Mr. Greenwood, a Republican who served six terms as a US Representative from Pennsylvania and was a founder of the House Oceans Caucus before leaving Congress and becoming President of the Biotechnology Industry Organization.
"If the President ultimately acts to protect these amazing areas of ocean to the fullest extent," said Mr. Greenwood, "his conservation legacy will rival that of President Teddy Roosevelt. Leadership in protecting our planet can and must come from Republicans and Democrats alike," he continued. "The fate of our oceans is far more important than partisan politics."
Large fish species, corals and vulnerable marine ecosystems are disappearing around the world. In the last several decades, 90% of big fishes including bluefin tunas, blue marlin and large groupers, have been wiped out. A growing number of marine scientists around the world believe that fully protected no-take marine reserves are the most powerful way to counter these losses.
Dr. Earle, Mr. Greenwood, and MCBI and EDF staff members met repeatedly with high-level Bush Administration officials, encouraging them to safeguard the waters surrounding various Central Pacific islands and Rose Atoll in American Samoa, among other sites.
"The President's announcement is highly encouraging," said William J. Chandler, Vice President for Government Affairs at Marine Conservation Biology Institute. "By using his presidential powers under the Antiquities Act and other statutes to fully protect ocean areas like he did in Hawaii, President Bush could write a new chapter in the history of conservation."
"This could be the best thing ever for ocean conservation. These vast Pacific areas are nearly three times the size of Texas," said Dr. Elliott A. Norse, founder and President of Marine Conservation Biology Institute. "Indeed, they're bigger than Mexico. Countless seabirds, dolphins, fishes, corals and tiny things as yet undiscovered could survive as a result, free of the threats that are eliminating them elsewhere, if the President gives full protection to these areas. I am thrilled that President Bush is considering this," said Dr. Norse.
The world's coral reefs and coral species are in trouble. The National Oceanic and Atmospheric Administration recently reported that nearly half of US coral reefs are in poor to fair condition. And a large group of international scientists recently reported that one-third of reef-building corals face elevated extinction risk from climate change and local impacts. The areas being considered are coral islands, atolls and reefs that are US territories and possessions in the Central Pacific Ocean, including Baker, Howland, Jarvis, Johnston, Kingman, Palmyra, Wake and Rose. Dr. Earle, Dr. Norse and 192 other American marine scientists recently called upon President Bush to give strong permanent protection to these reefs and their surroundings. The Governor of American Samoa, Togiola T.A. Tulafono has requested the President designate Rose Atoll in American Samoa as a national monument.
Marine Conservation Biology Institute is a nonprofit organization dedicated to advancing the science of marine conservation biology and securing protection for the world's marine ecosystems. Founded in 1996, MCBI is headquartered in Bellevue, WA, and has offices in Honolulu, HI, Glen Ellen, CA and Washington, DC.
Ike Spills Half a Million Gallons of Oil
By AP/DINA CAPPIELLO, FRANK BASS and CAIN BURDEAU Sunday, Oct. 05, 2008
(WASHINGTON) — Hurricane Ike's winds and massive waves destroyed oil platforms, tossed storage tanks and punctured pipelines. The environmental damage only now is becoming apparent: At least a half million gallons of crude oil spilled into the Gulf of Mexico and the marshes, bayous and bays of Louisiana and Texas, according to an analysis of federal data by The Associated Press.
In the days before and after the deadly storm, companies and residents reported at least 448 releases of oil, gasoline and dozens of other substances into the air and water and onto the ground in Louisiana and Texas. The hardest hit places were industrial centers near Houston and Port Arthur, Texas, as well as oil production facilities off Louisiana's coast, according to the AP's analysis.
"We are dealing with a multitude of different types of pollution here ... everything from diesel in the water to gasoline to things like household chemicals," said Larry Chambers, a petty officer with the U.S. Coast Guard Command Center in Pasadena, Texas.
The Coast Guard, with the Environmental Protection Agency and state agencies, has responded to more than 3,000 pollution reports associated with the storm and its surge along the upper Texas coast. Most callers complain about abandoned propane tanks, paint cans and other hazardous materials containers turning up in marshes, backyards and other places.
No major oil spills or hazardous materials releases have been identified, but nearly 1,500 sites still need to be cleaned up.
The Coast Guard's National Response Center in Washington collects information on oil spills and chemical and biological releases and passes it to agencies working on the ground. The AP analyzed all reports received by the center from Sept. 11 through Sept. 18 for Louisiana and Texas, providing an early snapshot of Ike's environmental toll.
With the storm approaching, refineries and chemical plants shut down as a precaution, burning off hundreds of thousands of pounds of organic compounds and toxic chemicals. In other cases, power failures sent chemicals such as ammonia directly into the atmosphere. Such accidental releases probably will not result in penalties by regulators because the releases are being blamed on the storm.
Texas Gov. Rick Perry also suspended all rules, including environmental ones, that would inhibit or prevent companies preparing for or responding to Ike.
Power outages also caused sewage pipes to stop flowing. Elsewhere, the storm's surge dredged up smelly and oxygen-deprived marsh mud, which killed fish and caused residents to complain of nausea and headaches from the odor.
At times, a new spill or release was reported to the Coast Guard every five minutes to 10 minutes. Some were extremely detailed, such as this report from Sept. 14: "Caller is making a report of a 6-by-4-foot container that was found floating in the Houston Ship Channel. Caller states the container was also labeled 'UM 3264,' which is a corrosive material." The caller most likely meant UN3264, an industrial coding that refers to a variety of different acids.
State and federal officials have collected thousands of abandoned drums, paint cans and other containers.
Other reports were more vague. One caller reported a sheen from an underwater pipeline and said the substance was "spewing" from the pipe.
The AP's analysis found that, by far, the most common contaminant left in Ike's wake was crude oil — the lifeblood and main industry of both Texas and Louisiana. In the week of reports analyzed, enough crude oil was spilled nearly to fill an Olympic-sized swimming pool, and more could be released, officials said, as platforms and pipelines were turned back on.
The Minerals Management Service, which oversees oil production in federal waters offshore, said the storm destroyed at least 52 oil platforms of roughly 3,800 in the Gulf of Mexico. Thirty-two more were severely damaged. But there was only one confirmed report of an oil spill — a leak of 8,400 gallons that officials said left no trace because it dissipated with the winds and currents.
Air contaminants were the second-most common release, mostly from the chemical plants and refineries along the coast.
About half the crude oil was reported spilled at a facility operated by St. Mary Land and Exploration Co. on Goat Island, Texas, a spit of uninhabited land north of the heavily damaged Bolivar Peninsula. The surge from the storm flooded the plant, leveling its dirt containment wall and snapping off the pipes connecting its eight storage tanks, which held the oil and water produced from two wells in Galveston Bay.
By the time the company reached the wreckage by boat more than 24 hours after Ike's landfall, the tanks were empty. Only a spattering of the roughly 266,000 gallons of oil spilled was left, and that is already cleaned up, according to Greg Leyendecker, the company's regional manager. The rest vanished, likely into the Gulf of Mexico.
Ike's fury might have helped prevent worse environmental damage. Its rough water, heavy rains and wind helped disperse pollution.
Air quality tests by Texas environmental regulators found no problems even in communities near industrial complexes, where power outages and high winds in some cases knocked out emergency devices that safely burn off chemicals. But the storm also zapped many of the state's permanent air pollution monitors in the region.
"We came out of this a lot better than we could have been, especially thinking where the storm hit," said Kelly Cook, the homeland security coordinator for the Texas Commission on Environmental Quality.
Katrina ranked as among the worst environmental disasters in U.S. history, with about 9 million gallons of oil spilled. But Ike's storm surge was less severe than feared — 12 feet rather than 20-feet plus — and the dikes, levees and bulkheads built around the region's heavy industry mostly held.
Much of that infrastructure is protected by a 1960s-era Army Corps of Engineers system of 15-foot levees similar to the one around New Orleans that failed catastrophically during Katrina. In that storm, floodwaters dislodged an oil tank at a Murphy Oil Corp. refinery in Meraux, La., spilling more than 1 million gallons of oil into the surrounding neighborhoods, canals and playgrounds.
Ike's toll on wildlife is still unfolding. Only a few pelicans and osprey turned up oiled, but the storm upended nature. Winds blew more than 1,000 baby squirrels from their nests. The storm's surge pushed saltwater into freshwater marshes and bayous, killing grasses where cattle graze and displacing alligators. Flooding also stranded cows.
The storm also may mangle migration. The Texas coast is a pit stop for birds heading south for the winter. But Ike wiped out many of their food sources, stripping berries from trees and nectar-producing flowers from plants, said Gina Donovan, executive director of the Houston Audubon Society, which operates 17 bird sanctuaries in Texas.
"It is going to cause wildlife to suffer for awhile," she said.
Along the Houston Ship Channel, a tanker truck floating in 12-feet-high flood waters slammed into a storage tank at the largest biodiesel refinery in the country, causing a leak of roughly 2,100 gallons of vegetable oil. The plant, owned by GreenHunter Energy Inc., uses chicken fat and beef tallow to make biodiesel shipped overseas. It opened just months earlier.
Oneal Galloway of Slidell, La., called to report oil in his neighborhood. The town, north of Lake Pontchartrain, was flooded with Ike's surge. He said oil had washed down the streets.
"It looked like a rainbow in the water," Galloway told the AP. "The residue of the oil is all over our fences, there were brown spots in the yard where it killed the grass."
The likely culprit was not a refinery or oil well, according to Shannon Davis, the director of the parish's public works department, but a neighbor brewing biodiesel in his backyard with used cooking grease.
(WASHINGTON) — Hurricane Ike's winds and massive waves destroyed oil platforms, tossed storage tanks and punctured pipelines. The environmental damage only now is becoming apparent: At least a half million gallons of crude oil spilled into the Gulf of Mexico and the marshes, bayous and bays of Louisiana and Texas, according to an analysis of federal data by The Associated Press.
In the days before and after the deadly storm, companies and residents reported at least 448 releases of oil, gasoline and dozens of other substances into the air and water and onto the ground in Louisiana and Texas. The hardest hit places were industrial centers near Houston and Port Arthur, Texas, as well as oil production facilities off Louisiana's coast, according to the AP's analysis.
"We are dealing with a multitude of different types of pollution here ... everything from diesel in the water to gasoline to things like household chemicals," said Larry Chambers, a petty officer with the U.S. Coast Guard Command Center in Pasadena, Texas.
The Coast Guard, with the Environmental Protection Agency and state agencies, has responded to more than 3,000 pollution reports associated with the storm and its surge along the upper Texas coast. Most callers complain about abandoned propane tanks, paint cans and other hazardous materials containers turning up in marshes, backyards and other places.
No major oil spills or hazardous materials releases have been identified, but nearly 1,500 sites still need to be cleaned up.
The Coast Guard's National Response Center in Washington collects information on oil spills and chemical and biological releases and passes it to agencies working on the ground. The AP analyzed all reports received by the center from Sept. 11 through Sept. 18 for Louisiana and Texas, providing an early snapshot of Ike's environmental toll.
With the storm approaching, refineries and chemical plants shut down as a precaution, burning off hundreds of thousands of pounds of organic compounds and toxic chemicals. In other cases, power failures sent chemicals such as ammonia directly into the atmosphere. Such accidental releases probably will not result in penalties by regulators because the releases are being blamed on the storm.
Texas Gov. Rick Perry also suspended all rules, including environmental ones, that would inhibit or prevent companies preparing for or responding to Ike.
Power outages also caused sewage pipes to stop flowing. Elsewhere, the storm's surge dredged up smelly and oxygen-deprived marsh mud, which killed fish and caused residents to complain of nausea and headaches from the odor.
At times, a new spill or release was reported to the Coast Guard every five minutes to 10 minutes. Some were extremely detailed, such as this report from Sept. 14: "Caller is making a report of a 6-by-4-foot container that was found floating in the Houston Ship Channel. Caller states the container was also labeled 'UM 3264,' which is a corrosive material." The caller most likely meant UN3264, an industrial coding that refers to a variety of different acids.
State and federal officials have collected thousands of abandoned drums, paint cans and other containers.
Other reports were more vague. One caller reported a sheen from an underwater pipeline and said the substance was "spewing" from the pipe.
The AP's analysis found that, by far, the most common contaminant left in Ike's wake was crude oil — the lifeblood and main industry of both Texas and Louisiana. In the week of reports analyzed, enough crude oil was spilled nearly to fill an Olympic-sized swimming pool, and more could be released, officials said, as platforms and pipelines were turned back on.
The Minerals Management Service, which oversees oil production in federal waters offshore, said the storm destroyed at least 52 oil platforms of roughly 3,800 in the Gulf of Mexico. Thirty-two more were severely damaged. But there was only one confirmed report of an oil spill — a leak of 8,400 gallons that officials said left no trace because it dissipated with the winds and currents.
Air contaminants were the second-most common release, mostly from the chemical plants and refineries along the coast.
About half the crude oil was reported spilled at a facility operated by St. Mary Land and Exploration Co. on Goat Island, Texas, a spit of uninhabited land north of the heavily damaged Bolivar Peninsula. The surge from the storm flooded the plant, leveling its dirt containment wall and snapping off the pipes connecting its eight storage tanks, which held the oil and water produced from two wells in Galveston Bay.
By the time the company reached the wreckage by boat more than 24 hours after Ike's landfall, the tanks were empty. Only a spattering of the roughly 266,000 gallons of oil spilled was left, and that is already cleaned up, according to Greg Leyendecker, the company's regional manager. The rest vanished, likely into the Gulf of Mexico.
Ike's fury might have helped prevent worse environmental damage. Its rough water, heavy rains and wind helped disperse pollution.
Air quality tests by Texas environmental regulators found no problems even in communities near industrial complexes, where power outages and high winds in some cases knocked out emergency devices that safely burn off chemicals. But the storm also zapped many of the state's permanent air pollution monitors in the region.
"We came out of this a lot better than we could have been, especially thinking where the storm hit," said Kelly Cook, the homeland security coordinator for the Texas Commission on Environmental Quality.
Katrina ranked as among the worst environmental disasters in U.S. history, with about 9 million gallons of oil spilled. But Ike's storm surge was less severe than feared — 12 feet rather than 20-feet plus — and the dikes, levees and bulkheads built around the region's heavy industry mostly held.
Much of that infrastructure is protected by a 1960s-era Army Corps of Engineers system of 15-foot levees similar to the one around New Orleans that failed catastrophically during Katrina. In that storm, floodwaters dislodged an oil tank at a Murphy Oil Corp. refinery in Meraux, La., spilling more than 1 million gallons of oil into the surrounding neighborhoods, canals and playgrounds.
Ike's toll on wildlife is still unfolding. Only a few pelicans and osprey turned up oiled, but the storm upended nature. Winds blew more than 1,000 baby squirrels from their nests. The storm's surge pushed saltwater into freshwater marshes and bayous, killing grasses where cattle graze and displacing alligators. Flooding also stranded cows.
The storm also may mangle migration. The Texas coast is a pit stop for birds heading south for the winter. But Ike wiped out many of their food sources, stripping berries from trees and nectar-producing flowers from plants, said Gina Donovan, executive director of the Houston Audubon Society, which operates 17 bird sanctuaries in Texas.
"It is going to cause wildlife to suffer for awhile," she said.
Along the Houston Ship Channel, a tanker truck floating in 12-feet-high flood waters slammed into a storage tank at the largest biodiesel refinery in the country, causing a leak of roughly 2,100 gallons of vegetable oil. The plant, owned by GreenHunter Energy Inc., uses chicken fat and beef tallow to make biodiesel shipped overseas. It opened just months earlier.
Oneal Galloway of Slidell, La., called to report oil in his neighborhood. The town, north of Lake Pontchartrain, was flooded with Ike's surge. He said oil had washed down the streets.
"It looked like a rainbow in the water," Galloway told the AP. "The residue of the oil is all over our fences, there were brown spots in the yard where it killed the grass."
The likely culprit was not a refinery or oil well, according to Shannon Davis, the director of the parish's public works department, but a neighbor brewing biodiesel in his backyard with used cooking grease.
Thursday, October 9, 2008
National Geographic - Jewels of the Carribean Sea
i found this video on you tube and i thought i would share the beauty of the carribean sea with our class! our oceans are such a vast wonderful place just waiting to be explored!
http://www.youtube.com/watch?v=a-xhy16pB4s&feature=related
http://www.youtube.com/watch?v=a-xhy16pB4s&feature=related
113 New Sharks and Rays Announced in Australia
Dave Hansford in Wellington, New Zealandfor National Geographic News
September 21, 2008
DNA evidence has helped identify 113 new sharks and rays—including a skinny saw shark, a swell shark that looks like it swallowed a Frisbee, and a river shark (see photos)—scientists announced Thursday.
Nearly half of the newly named sharks and other species are found only around Australia. The discoveries increase the continent's tally of known sharks and rays by a third. One of the new fish, the collared carpet shark, is so rare that the only known specimen was found in the belly of another shark.
September 21, 2008
DNA evidence has helped identify 113 new sharks and rays—including a skinny saw shark, a swell shark that looks like it swallowed a Frisbee, and a river shark (see photos)—scientists announced Thursday.
Nearly half of the newly named sharks and other species are found only around Australia. The discoveries increase the continent's tally of known sharks and rays by a third. One of the new fish, the collared carpet shark, is so rare that the only known specimen was found in the belly of another shark.
Some of the new species are already threatened with extinction, scientists say, and many of the sharks and rays have yet to be named.
(Also see: "New Sharks, Rays Discovered in Indonesia Fish Markets" [March 31, 2007].)
Defined by DNA
During the 18-month study, researchers used genetic techniques to help scientifically describe, for the first time, species already in museum collections in Australia, New Zealand, and Europe.
"We reviewed the entire shark and ray fauna," said fish taxonomist Peter Last, who led the project for Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO).
At first glance, some of the fish appear very similar, making it tough to tell different species apart. Some even share the same habitat. "Quite often, they will swim together," Last said.
Existing descriptions—many of them brief and lacking detail—weren't much help, Last said.
But by analyzing the species' DNA, the scientists were able to uncover invisible distinctions.
"In some cases, what was thought to be a single species of shark turned out to be something like five species," he said.
Among these previously "hidden" species is the newly described maugean skate, already listed as endangered by the International Union for the Conservation of Nature.
(Also see: "New Sharks, Rays Discovered in Indonesia Fish Markets" [March 31, 2007].)
Defined by DNA
During the 18-month study, researchers used genetic techniques to help scientifically describe, for the first time, species already in museum collections in Australia, New Zealand, and Europe.
"We reviewed the entire shark and ray fauna," said fish taxonomist Peter Last, who led the project for Australia's Commonwealth Scientific and Industrial Research Organisation (CSIRO).
At first glance, some of the fish appear very similar, making it tough to tell different species apart. Some even share the same habitat. "Quite often, they will swim together," Last said.
Existing descriptions—many of them brief and lacking detail—weren't much help, Last said.
But by analyzing the species' DNA, the scientists were able to uncover invisible distinctions.
"In some cases, what was thought to be a single species of shark turned out to be something like five species," he said.
Among these previously "hidden" species is the newly described maugean skate, already listed as endangered by the International Union for the Conservation of Nature.
Found in "three little estuaries" off the Australian island of Tasmania, the maugean skate is very similar to a species found on the other side of the world, off southern South America. Before breaking apart about 160 million years ago, Australia and South America were joined in the supercontinent Gondwana.
The similarity of the two skate species suggests that they were once a single species that plied Gondwana coastal waters, Last said. Since the breakup, the skates have hugged the coasts of Australia and South America, he said.
The similarity of the two skate species suggests that they were once a single species that plied Gondwana coastal waters, Last said. Since the breakup, the skates have hugged the coasts of Australia and South America, he said.
These animals have simply remained on the edges of the fragments of [the former Gondwana continental] plate all that time, without changing much"—though enough to now be considered separate species.
Lost Before Found?
Most of the new species—such as the southern dogfish, a gulper shark—live along Australia's continental shelf, a very narrow plateau that plunges steeply to the open deeps.
Living in this narrow ribbon of shallow water places the species in the path of trawlers, where the fish are vulnerable to overfishing.
Some species could go extinct before they are even fully described, Last said—a particularly consequence when top predators are involved.
"If you take the top predators out of the food chain, it can have serious implications for the rest of the ecosystem," he told National Geographic News.
"Part of the problem is … we've tended to try and manage groups of species rather than single species, and the biology of single species can be very different to groups," Last told the Australian Broadcasting Corporation yesterday.
Clive Roberts, curator of fish at the Museum of New Zealand, said, "A lot of these sharks are slow growing. They're long-lived and relatively slow reproducers, only dropping pups perhaps every second year.
"Because they are vulnerable to fishing, they become locally extinct fairly quickly," Roberts said. "That's been well documented around Australian waters."
More to Come
New large marine species will continue to turn up, he added.
"We're still describing new species from 10 or 13 feet [3 or 4 metres] depth, so it's no surprise that there are heaps of undescribed stuff further down.
"We need to know what we've got, and where it is," Roberts said. "We need to know what species it is and manage it, conserve it, or exploit it in a responsible way."
Lost Before Found?
Most of the new species—such as the southern dogfish, a gulper shark—live along Australia's continental shelf, a very narrow plateau that plunges steeply to the open deeps.
Living in this narrow ribbon of shallow water places the species in the path of trawlers, where the fish are vulnerable to overfishing.
Some species could go extinct before they are even fully described, Last said—a particularly consequence when top predators are involved.
"If you take the top predators out of the food chain, it can have serious implications for the rest of the ecosystem," he told National Geographic News.
"Part of the problem is … we've tended to try and manage groups of species rather than single species, and the biology of single species can be very different to groups," Last told the Australian Broadcasting Corporation yesterday.
Clive Roberts, curator of fish at the Museum of New Zealand, said, "A lot of these sharks are slow growing. They're long-lived and relatively slow reproducers, only dropping pups perhaps every second year.
"Because they are vulnerable to fishing, they become locally extinct fairly quickly," Roberts said. "That's been well documented around Australian waters."
More to Come
New large marine species will continue to turn up, he added.
"We're still describing new species from 10 or 13 feet [3 or 4 metres] depth, so it's no surprise that there are heaps of undescribed stuff further down.
"We need to know what we've got, and where it is," Roberts said. "We need to know what species it is and manage it, conserve it, or exploit it in a responsible way."
Tuesday, October 7, 2008
Dimethylsulfide Emission: Climate Control by Marine Algae?
Article by Katina Bucher Norris
Review Article
Introduction
Ever notice the salty sea smell when you're out on or near the ocean? It's the salt spray tossed from wind-driven white caps and breaking waves, but the smell isn't from the salt alone. Gases diffuse across the air-sea interface, many of which are synthesized and emitted by microalgae. One of these gases is a sulfur based compound that has a strong characteristic odor. It has been suggested that variations in algal production of these natural gases play an important role in moderating our climate through their aerosols' effect on backscattering solar radiation and in cloud formation.1 Trace concentrations of a sulfurous gas were discovered in the Earth's atmosphere about three decades ago. The gas was also found to occur in ocean surface waters. Scientists have identified the sulfurous gas as dimethylsulfide (DMS). While it may sound like a noxious pollutant, dimethylsulfide is a naturally produced biogenic gas essential for the Earth's biogeochemical cycles. Learning more about this crucial gas will enhance our understanding of food chains and global scale climate processes, and allow for more intelligent environmental management.
In the ocean dimethylsulfide is produced through a web of biological interactions. Certain species of phytoplankton, microscopic algae in the upper ocean, synthesize the molecule dimethylsulfoniopropionate (DMSP) which is the precursor to DMS.2 When phytoplankton cells are damaged, for example by grazing zooplankton or viral lysis, they release their contents into the seawater. Bacteria and phytoplankton are involved in degrading the released algal sulfurous compound DMSP to DMS and other products. A portion of the DMS diffuses from saltwater to the atmosphere. Once it is transferred to the atmosphere the gaseous DMS is oxidized to tropospheric sulfate aerosols, and these particulate aerosols act as cloud condensation nuclei (CCN), attracting molecules of water. Water vapor condenses on these CCN particles, forming the water droplets that make up clouds.3 Clouds affect the Earths radiation balance and thereby greatly influence its temperature and climate. DMS represents 95% of the natural marine flux of sulfur gases to the atmosphere, and scientists estimate that the flux of marine DMS supplies about 50% of the global biogenic source of sulfur to the atmosphere
In the ocean dimethylsulfide is produced through a web of biological interactions. Certain species of phytoplankton, microscopic algae in the upper ocean, synthesize the molecule dimethylsulfoniopropionate (DMSP) which is the precursor to DMS.2 When phytoplankton cells are damaged, for example by grazing zooplankton or viral lysis, they release their contents into the seawater. Bacteria and phytoplankton are involved in degrading the released algal sulfurous compound DMSP to DMS and other products. A portion of the DMS diffuses from saltwater to the atmosphere. Once it is transferred to the atmosphere the gaseous DMS is oxidized to tropospheric sulfate aerosols, and these particulate aerosols act as cloud condensation nuclei (CCN), attracting molecules of water. Water vapor condenses on these CCN particles, forming the water droplets that make up clouds.3 Clouds affect the Earths radiation balance and thereby greatly influence its temperature and climate. DMS represents 95% of the natural marine flux of sulfur gases to the atmosphere, and scientists estimate that the flux of marine DMS supplies about 50% of the global biogenic source of sulfur to the atmosphere
The Production of DMS
Marine phytoplankton live in the sunlit waters of the world's upper oceans, an ecosystem covering about two thirds of the planet. Dimethylsulfoniopropionate produced within phytoplankton cells is thought to have a number of important physiological functions. Some microalgal species contain a high percentage of intercellular DMSP. This compound may act as an osmolyte, a neutral solute that reacts minimally with the contents of the cell while protecting it from drying out, or in the cell's response to salinity changes.5 In cold environments DMSP may act as a cryoprotectant, protecting the cell from freezing. It has also been suggested that DMSP acts as an antioxidant, scavenging free radicals and helping the algae to tolerate stressful conditions, such as high solar radiation or iron deficient water.6 Research indicates a direct link between oxidative stressors and the dynamics of DMSP and DMS in marine phytoplankton.7
The synthesis of the volatile organic compound DMS seems to be species specific. While many algae do produce high concentrations of DMS, for example prymesiophytes and dinoflagellates, including many bloom forming taxa e.g. Phaeocystis, Emiliania, and Alexandrium, lesser amounts are found in other phytoplankton.8 There is not a linear relationship between the concentration of DMS in ocean surface waters and the density of phytoplankton, because different phytoplankton have DMSP in varying amounts and not all have the enzyme DMSP-lyase. The DMS concentration is dependent on numerous biotic interactions, most not well understood yet, as investigating the microbial food web is a technical challenge.
The DMS concentration results from the combined effects of DMSP production and removal processes. DMSP is release by damaged phytoplankton cells due to physical stress (e.g. turbulence, zooplankton grazing or viral lysis) and subsequently transformed by phytoplankton and bacterial enzymes to DMS. Many bacteria have DMSP-lyase and are thought to play a significant part in converting the algal DMSP to DMS, while other types of bacteria consume the DMSP.9 Photochemical reactions and ultraviolet radiation can degrade DMS to further break down products, removing DMS. The rate of DMS flux to the atmosphere is primarily dependent on its concentration in sea water.
The synthesis of the volatile organic compound DMS seems to be species specific. While many algae do produce high concentrations of DMS, for example prymesiophytes and dinoflagellates, including many bloom forming taxa e.g. Phaeocystis, Emiliania, and Alexandrium, lesser amounts are found in other phytoplankton.8 There is not a linear relationship between the concentration of DMS in ocean surface waters and the density of phytoplankton, because different phytoplankton have DMSP in varying amounts and not all have the enzyme DMSP-lyase. The DMS concentration is dependent on numerous biotic interactions, most not well understood yet, as investigating the microbial food web is a technical challenge.
The DMS concentration results from the combined effects of DMSP production and removal processes. DMSP is release by damaged phytoplankton cells due to physical stress (e.g. turbulence, zooplankton grazing or viral lysis) and subsequently transformed by phytoplankton and bacterial enzymes to DMS. Many bacteria have DMSP-lyase and are thought to play a significant part in converting the algal DMSP to DMS, while other types of bacteria consume the DMSP.9 Photochemical reactions and ultraviolet radiation can degrade DMS to further break down products, removing DMS. The rate of DMS flux to the atmosphere is primarily dependent on its concentration in sea water.
DMS Effects on Grazing
DMSP degradation products (i.e. DMS and acrylate) may also act as deterrents to grazing by herbivores. These compounds are released from phytoplankton when they are damaged by grazing zooplankton (e.g. ciliates, tintinnids, copepods, fish and invertebrate larvae).10 Certain species of phytoplankton contain DMSP-lyase that quickly converts the benign DMSP to the unpalatable DMS and acrylate when the cell is injured. These sulfurous compounds that have been proposed to act as chemical defenses against consumption by zooplankton. In feeding experiments, Wolfe et al. found that zooplankton grazers, including protozoan herbivores, prefer to consume algae without DMSP-lyase.11
Some species of the larger ocean plants, the seaweeds, also contain DMSP, and ecologists are determining whether the compound or its breakdown products are a deterrent to herbivore consumption as well. Van Alstyne et al. surveyed Pacific seaweeds growing along the shores of Oregon and Washington, and detected DMSP in numerous green algal species and in one red alga.12 DMSP-lyase activity was found in Ulva fenestra and Polysiphonia hendryi, so these species have the enzyme to convert DMSP to DMS and depending upon the pH, either acrylate or acrylic acid. In laboratory feeding preference trials, sea urchins (Strongylocentrotus) were attracted to diets containing DMSP and avoided diets containing acrylic acid, except at the lowest test concentration. Acrylic acid appears to be a successful deterrent against the two sea urchin species tested, but it did not discourage the herbivorous crustacean Idotea from feeding.13
Some species of the larger ocean plants, the seaweeds, also contain DMSP, and ecologists are determining whether the compound or its breakdown products are a deterrent to herbivore consumption as well. Van Alstyne et al. surveyed Pacific seaweeds growing along the shores of Oregon and Washington, and detected DMSP in numerous green algal species and in one red alga.12 DMSP-lyase activity was found in Ulva fenestra and Polysiphonia hendryi, so these species have the enzyme to convert DMSP to DMS and depending upon the pH, either acrylate or acrylic acid. In laboratory feeding preference trials, sea urchins (Strongylocentrotus) were attracted to diets containing DMSP and avoided diets containing acrylic acid, except at the lowest test concentration. Acrylic acid appears to be a successful deterrent against the two sea urchin species tested, but it did not discourage the herbivorous crustacean Idotea from feeding.13
The Transfer of DMS to the Air and the Marine Food Web
Along Antarctic polar fronts, upwelling brings nutrient rich water to the surface, supporting dense algal blooms. Zooplankton, including krill (Euphausia superba), exploit this enriched environment by swarming to feed on these phytoplankton blooms. As the phytoplankton are consumed, DMSP is released and converted to DMS, and a portion of it is volatized to the atmospheric boundary layer. In fact, elevated concentrations of DMS above the ocean surface can be an indication of dense aggregations of zooplankton feeding beneath the surface. Other animals within the Antarctic marine food web (e.g. fish and squid) are also abundant in these more productive environs.
Large populations of Antarctic procellariiform seabirds are also associated with sites of high DMS concentrations.14 Field tests indicate that these birds are sensitive to a variety of odors associated with their prey, including the odors of phytoplankton (DMS) and krill. Nevitt hypothesized that these seabirds may have an excellent sense of smell and use the sulfurous gas to locate the most productive feeding grounds in the visually monotonous open sea environment.15 Using DMS as a foraging cue would improve the birds' success, as the odor guides them to areas of higher productivity and greater densities of prey (krill and other crustaceans). Procellariiform seabirds have evolved large, well-developed olfactory organs.
Nevitt et al. set up experiments in sub-Antarctic waters, near South Georgia, deploying DMS-scented surface slicks in one area and controls of slicks without DMS scent in a second area to observe the birds' behavioral responses.16 Results from paired slick experiments showed that some species of petrels and other birds can detect and are attracted to the DMS-scented surface slicks, while other birds which are probably visual predators, were not. In another experiment, DMS was wafted in air plumes to observe the birds' flight behavior. The same species that were attracted to scented slicks turned in response toward the air-borne DMS. DMS is part of the olfactory landscape over the Antarctic Ocean. Planktivorous seabirds seem to use DMS as an olfactory signal to navigate to zooplankton-rich sites.17
Large populations of Antarctic procellariiform seabirds are also associated with sites of high DMS concentrations.14 Field tests indicate that these birds are sensitive to a variety of odors associated with their prey, including the odors of phytoplankton (DMS) and krill. Nevitt hypothesized that these seabirds may have an excellent sense of smell and use the sulfurous gas to locate the most productive feeding grounds in the visually monotonous open sea environment.15 Using DMS as a foraging cue would improve the birds' success, as the odor guides them to areas of higher productivity and greater densities of prey (krill and other crustaceans). Procellariiform seabirds have evolved large, well-developed olfactory organs.
Nevitt et al. set up experiments in sub-Antarctic waters, near South Georgia, deploying DMS-scented surface slicks in one area and controls of slicks without DMS scent in a second area to observe the birds' behavioral responses.16 Results from paired slick experiments showed that some species of petrels and other birds can detect and are attracted to the DMS-scented surface slicks, while other birds which are probably visual predators, were not. In another experiment, DMS was wafted in air plumes to observe the birds' flight behavior. The same species that were attracted to scented slicks turned in response toward the air-borne DMS. DMS is part of the olfactory landscape over the Antarctic Ocean. Planktivorous seabirds seem to use DMS as an olfactory signal to navigate to zooplankton-rich sites.17
DMS and the Global Sulfur Cycle and Climate
A key process in the sulfur cycle is the transfer of volatile sulfur compounds from the sea to the land via the atmosphere. DMS is the dominant biogenic sulfur compound in the marine atmosphere and essential to the global sulfur cycle. The gaseous DMS is photo-oxidized to sulfated aerosols in the atmosphere. Berresheim et al. established a relationship between DMS, sulfate aerosols, and cloud condensation nuclei.18 Because the sulfate aerosols function as cloud condensation nuclei, DMS has a significant impact on the Earth's climate. Plankton production of DMS and its escape to the atmosphere is believed to be one of the mechanisms by which the biota can regulate the climate.
see figure at the top of article
The radiation balance has a fundamental effect on Earth's climate. About one third of the solar radiation that reaches the Earth is reflected back into space by clouds and from earth surfaces, such as ice and snow. The atmosphere absorbs some solar energy, but most of the other two thirds is absorbed by the land and oceans, which are warmed by the sunlight. The sun's energy is converted into heat, and the land and oceans then radiate a portion of this energy back as outgoing long-wave radiation (infrared), also known as terrestrial radiation. As this energy is radiated back out, it warms the atmosphere and continues on into space. The amount of solar energy received by the Earth, the planetary albedo (the amount reflected back) and the emitted terrestrial radiation, makes up the Earth's radiation balance. If the Earth receives more energy than it loses, the result is global warming, and if it loses more energy than it receives, the result is global cooling.
Albedo is an important factor in the radiation balance, and clouds have the major effect on albedo. The optical properties of a cloud are a key issue to understanding and therefore predicting global climate change. A cloud's optical properties are related to the size distribution and number of its droplets. The more cloud condensation nuclei, the smaller the size of its water droplets and the higher the density of water droplets since the same amount of water vapor is distributed among a greater number of CCN.19 This affects the radiative properties (reflectance, transmittance and absorbance) of the cloud.
Clouds affect both incoming solar and outgoing thermal infrared fluxes; low thick clouds act as shields, blocking and reflecting solar radiation back into space which cools the planet, but high clouds can also trap outgoing heat (longwave radiation), warming the planet. Data indicate that clouds have an overall net cooling effect.20 The smaller droplet size will likely decrease precipitation, resulting in a longer lifetime for a cloud.21 Climate change scientists realized their models had a poor ability to reproduce the effects of clouds, so they set a priority to observe, measure and learn about clouds' physical properties and radiative fluxes. Several international programs (CERES and other projects) are observing clouds from space using multiple satellites to more accurately quantify cloud properties and their impact on albedo. The results of these programs will improve the modeling of cloud physics, so climate models will provide a more credible simulation of climate change projections. DMS may influence both the hydrologic cycle and the global heat budget through its part in cloud formation, and may alter rainfall patterns and temperatures.
Albedo is an important factor in the radiation balance, and clouds have the major effect on albedo. The optical properties of a cloud are a key issue to understanding and therefore predicting global climate change. A cloud's optical properties are related to the size distribution and number of its droplets. The more cloud condensation nuclei, the smaller the size of its water droplets and the higher the density of water droplets since the same amount of water vapor is distributed among a greater number of CCN.19 This affects the radiative properties (reflectance, transmittance and absorbance) of the cloud.
Clouds affect both incoming solar and outgoing thermal infrared fluxes; low thick clouds act as shields, blocking and reflecting solar radiation back into space which cools the planet, but high clouds can also trap outgoing heat (longwave radiation), warming the planet. Data indicate that clouds have an overall net cooling effect.20 The smaller droplet size will likely decrease precipitation, resulting in a longer lifetime for a cloud.21 Climate change scientists realized their models had a poor ability to reproduce the effects of clouds, so they set a priority to observe, measure and learn about clouds' physical properties and radiative fluxes. Several international programs (CERES and other projects) are observing clouds from space using multiple satellites to more accurately quantify cloud properties and their impact on albedo. The results of these programs will improve the modeling of cloud physics, so climate models will provide a more credible simulation of climate change projections. DMS may influence both the hydrologic cycle and the global heat budget through its part in cloud formation, and may alter rainfall patterns and temperatures.
The Earth as an Organism
Although progress has been made in understanding the biological, physical and chemical reactions in the DMS cycle, much remains to be investigated. In order to discover the factors controlling the atmospheric concentration of DMS, we need to know the following about what affects its production in the ocean and escape to the atmosphere: 1) which phytoplankton species are high in DMSP and which have DMSP-lyase, 2) the species composition of the phytoplankton community and its succession in an area, 3) their global distribution and population density, and 4) other biotic interactions that effect DMS concentrations (e.g. zooplankton and bacteria populations). Abiotic factors, such as sea surface temperature and mixed layer depth, also have a direct impact on DMS production.
The Gaia Hypothesis suggests that the Earth (biosphere and more) functions as an organism to maintain homeostasis, to keep the planet fit for life.22 NASA used the fact that organisms actively change the atmosphere' s chemistry through their living processes to search for extraterrestrial life. DMS is part of the Earth's ocean-atmosphere feedback loop, a climate stabilizing mechanism, moderating temperatures on Earth. Sciare et al. found a direct link between sea surface temperature and atmospheric DMS over a large area in the southern Indian Ocean. They estimate that an increase in temperature would increase the atmosphere's DMS concentration and have a negative feedback on the original warming.23
The photic zone is a complex habitat where phytoplankton, although tiny in size, through their number and volume are critical to Earth's natural cycles. Phytoplankton activities have global consequences on atmospheric chemistry through their production of oxygen, are the base of most ocean food chains, interact in the global carbon cycle by using the greenhouse gas carbon dioxide, and are a carbon sink through their sedimentation of carbonates to the sea floor. Microalgae also play an important role in mediating global climate through variations in DMS production and its influence on cloud formation.
It is imperative to understand the chemical reactions involving dimethylsulfide on a global scale, from polar to tropical waters, so that models can be developed to accurately estimate the natural and human impacts on atmospheric chemistry and climate. To be better stewards of our planet we need to understand its natural cycles, and the environmental consequences of human actions. As a practical measure we need to sustain our life support system, as we are all dependent on natural systems for breathable air, clean water, dependable rainfall, and temperature and climate stability.
The Gaia Hypothesis suggests that the Earth (biosphere and more) functions as an organism to maintain homeostasis, to keep the planet fit for life.22 NASA used the fact that organisms actively change the atmosphere' s chemistry through their living processes to search for extraterrestrial life. DMS is part of the Earth's ocean-atmosphere feedback loop, a climate stabilizing mechanism, moderating temperatures on Earth. Sciare et al. found a direct link between sea surface temperature and atmospheric DMS over a large area in the southern Indian Ocean. They estimate that an increase in temperature would increase the atmosphere's DMS concentration and have a negative feedback on the original warming.23
The photic zone is a complex habitat where phytoplankton, although tiny in size, through their number and volume are critical to Earth's natural cycles. Phytoplankton activities have global consequences on atmospheric chemistry through their production of oxygen, are the base of most ocean food chains, interact in the global carbon cycle by using the greenhouse gas carbon dioxide, and are a carbon sink through their sedimentation of carbonates to the sea floor. Microalgae also play an important role in mediating global climate through variations in DMS production and its influence on cloud formation.
It is imperative to understand the chemical reactions involving dimethylsulfide on a global scale, from polar to tropical waters, so that models can be developed to accurately estimate the natural and human impacts on atmospheric chemistry and climate. To be better stewards of our planet we need to understand its natural cycles, and the environmental consequences of human actions. As a practical measure we need to sustain our life support system, as we are all dependent on natural systems for breathable air, clean water, dependable rainfall, and temperature and climate stability.
© Copyright 2003, All Rights Reserved, CSA
Shaw, G.E. 1983. Bio-controlled thermostasis involving the sulfur cycle. Climatic Change 5, 297-303Andreae, M.O. 1985. In The Biogeochemical Cycling of Sulfur and Nitrogen in the Remote Atmosphere (eds. Galloway, J.N., Charlson, R.J., Andreae, M.O., & Rodhe, H.) 5-25 (Reidel, Dordrecht)Charlson, R.J. Lovelock, J.E., Andreae, M.O., and Warren, S.G. 1987. Oceanic phytoplankton, atmospheric sulfur, cloud albedo and climate: a geophysiological feedback. Nature 326;655-661
Simo , R, Archer, S.D; Pedros-Alio, C, Gilpin I; Stelfox-Widdiecombe, C.E. 2002 Coupled dynamics of dimethylsulfoniopropionate and dimethylsulfide cycling and the microbial food web in surface waters of the North Atlantic. Limnology and Oceanography Vol. 47, no. 1, pp. 53-61Niki, T, Kunugi, M, Otsuki, A. 2000 DMSP-lyase activity in five marine phytoplankton species: Its potential importance in DMS production. Mar Biol. Vol. 136, no. 5, pp. 759-764
Berresheim, H., F. L. Eisele, D. J. Tanner, L. M. McInnes, D. C. Ramseybell and D. S. Covert 1993, Atmospheric Sulfur Chemistry and Cloud Condensation Nuclei (Ccn) Concentrations over the Northeastern Pacific Coast. Journal of Geophysical Research-Atmospheres 98 (D7): 12701-12711
Andreae, M.O. 1990. Ocean-atmosphere interactions in the global biogeochemical . sulfur cycle. Mar. Chem. 30, 1-29Bates, T.S., Lamb, B.K, Guenther A., Dignon J. Stoiber, R.E. 1992. Sulfur emissions to the atmosphere from natural sources. J. Atoms. Chem. 14:315-337Liss, P.S. Hatton, A.D.. Malin, G. , Nightingale, P.D. Turner, S.M. 1997. Marine Sulphur Emissions. Phil Trans. R. Soc Lond. B. Biol. Sci. 352:159-169; Simo , R, Pedros-Alio, C, Malin G; Grimalt J.O. 2000 Biological turnover of DMS, DMSP and DMSO in contrasting open-sea waters. Mar Ecol. Prog. Ser. Vol. 203, pp 1-11
back to article
Kiene, R.P., Visscher, P.T., Keller, M.D, Kirst, G.O. (eds) 1996. Biological and Environmental Chemistry of DMSP and related Sulfonium Compounds. Plenum Press. New YorkCharlson, R.J. Lovelock, J.E., Andreae, M.O., and Warren, S.G. 1987. Oceanic phytoplankton, atmospheric sulfur, cloud albedo and climate: a geophysiological feedback. Nature 326;655-661
Sunda, W. Kieber, DJ. Kiene, R.P. Huntsman, S. 2002. An antioxidant function for DMSP and DMS in marine algae. Nature Vol. 418 no. 6895. pp. 317-320
Ibid.
Wolfe, G.V. 2000. The chemical defense ecology of marine unicellular plankton: constraints, mechanisms, and impacts. Biol. Bull. 198:225-244
Niki, T, Kunugi, M, Otsuki, A. 2000 DMSP-lyase activity in five marine phytoplankton species: Its potential importance in DMS production. Mar Biol. Vol. 136, no. 5, pp. 759-764
Archer, S.D. Stelfox-Widdicombe, C.E., Malin, G., Burkill, P.H. 2003. Is Dimethyl sulfide production related to microzooplankton herbivory in the southern North Sea? J. Plankton Research Vol. 25, no. 2, pp 235-242Hay, M.E., Kubanek, J. 2002 Community and ecosystem level consequences of chemical cues in the plankton. Journal of Chemical Ecology Vol 28, no. 20, pp 2001-2016
back to article
Wolfe, G.V., Steinke, M., Kirst, G.O. 1997. Grazing activated chemical defence in a unicellular marine alga. Nature vol. 387, no. 6636, pp. 894-897Wolfe, G.V. 2000. The chemical defense ecology of marine unicellular plankton: constraints, mechanisms, and impacts. Biol. Bull. 198:225-244
Van Alstyne, K.L., Wolfe, G.V., Freidenburg, T.L, Neill, A., Hicken, C. 2001. Activated defense systems in marine macroalgae: evidence for an ecological role for DMSP cleavage. Mar. Ecol. Prog. Ser.Vol. 213, pp 53-65
Ibid.
Nevitt, G.A. 2000. Olfactory foraging by Antarctic Procellariiform seabirds: life at high Reynolds numbers. Biol. Bull,198:245-253
Ibid.
back to article
Nevitt, G.A., Velt, R.R., Karelva, P. 1995. Dimethyl sulphide as a foraging cue for Antarctic Procellariiform seabirds. Nature Vol. 376, pp 680-682
Ibid.
Berresheim, H., F. L. Eisele, D. J. Tanner, L. M. McInnes, D. C. Ramseybell and D. S. Covert 1993, Atmospheric Sulfur Chemistry and Cloud Condensation Nuclei (Ccn) Concentrations over the Northeastern Pacific Coast. Journal of Geophysical Research-Atmospheres98 (D7): 12701-12711
Charlson, R.J. Lovelock, J.E., Andreae, M.O., and Warren, S.G. 1987. Oceanic phytoplankton, atmospheric sulfur, cloud albedo and climate: a geophysiological feedback. Nature326;655-661
http://asd-www.larc.nasa.gov/ceres/brochure/sci_priorities.html(Science Priorities, CERES, Clouds and the Earths Radiant Energy System, NASA Langley Research Center)
back to article
Kulmala, M. Laaksonen, A., Korhonen, P., Vesala, T. and Ahonen, T. 1993. The effect of atmospheric nitric acid vapor on cloud condensation nucleus activation, Journal of Geophysical Research98:22, 949-22,958
Lovelock, J. E. 1979. Gaia: A New Look at Life on Earth. Oxford University Press
Sciare, J., Mihalopoulos, N. and Dentener, F.J. 2000. Interannual variability of atmospheric dimethylsulfide in the southern Indian Ocean. Journal of Geophysical Research105: 26,369-26,377
Shaw, G.E. 1983. Bio-controlled thermostasis involving the sulfur cycle. Climatic Change 5, 297-303Andreae, M.O. 1985. In The Biogeochemical Cycling of Sulfur and Nitrogen in the Remote Atmosphere (eds. Galloway, J.N., Charlson, R.J., Andreae, M.O., & Rodhe, H.) 5-25 (Reidel, Dordrecht)Charlson, R.J. Lovelock, J.E., Andreae, M.O., and Warren, S.G. 1987. Oceanic phytoplankton, atmospheric sulfur, cloud albedo and climate: a geophysiological feedback. Nature 326;655-661
Simo , R, Archer, S.D; Pedros-Alio, C, Gilpin I; Stelfox-Widdiecombe, C.E. 2002 Coupled dynamics of dimethylsulfoniopropionate and dimethylsulfide cycling and the microbial food web in surface waters of the North Atlantic. Limnology and Oceanography Vol. 47, no. 1, pp. 53-61Niki, T, Kunugi, M, Otsuki, A. 2000 DMSP-lyase activity in five marine phytoplankton species: Its potential importance in DMS production. Mar Biol. Vol. 136, no. 5, pp. 759-764
Berresheim, H., F. L. Eisele, D. J. Tanner, L. M. McInnes, D. C. Ramseybell and D. S. Covert 1993, Atmospheric Sulfur Chemistry and Cloud Condensation Nuclei (Ccn) Concentrations over the Northeastern Pacific Coast. Journal of Geophysical Research-Atmospheres 98 (D7): 12701-12711
Andreae, M.O. 1990. Ocean-atmosphere interactions in the global biogeochemical . sulfur cycle. Mar. Chem. 30, 1-29Bates, T.S., Lamb, B.K, Guenther A., Dignon J. Stoiber, R.E. 1992. Sulfur emissions to the atmosphere from natural sources. J. Atoms. Chem. 14:315-337Liss, P.S. Hatton, A.D.. Malin, G. , Nightingale, P.D. Turner, S.M. 1997. Marine Sulphur Emissions. Phil Trans. R. Soc Lond. B. Biol. Sci. 352:159-169; Simo , R, Pedros-Alio, C, Malin G; Grimalt J.O. 2000 Biological turnover of DMS, DMSP and DMSO in contrasting open-sea waters. Mar Ecol. Prog. Ser. Vol. 203, pp 1-11
back to article
Kiene, R.P., Visscher, P.T., Keller, M.D, Kirst, G.O. (eds) 1996. Biological and Environmental Chemistry of DMSP and related Sulfonium Compounds. Plenum Press. New YorkCharlson, R.J. Lovelock, J.E., Andreae, M.O., and Warren, S.G. 1987. Oceanic phytoplankton, atmospheric sulfur, cloud albedo and climate: a geophysiological feedback. Nature 326;655-661
Sunda, W. Kieber, DJ. Kiene, R.P. Huntsman, S. 2002. An antioxidant function for DMSP and DMS in marine algae. Nature Vol. 418 no. 6895. pp. 317-320
Ibid.
Wolfe, G.V. 2000. The chemical defense ecology of marine unicellular plankton: constraints, mechanisms, and impacts. Biol. Bull. 198:225-244
Niki, T, Kunugi, M, Otsuki, A. 2000 DMSP-lyase activity in five marine phytoplankton species: Its potential importance in DMS production. Mar Biol. Vol. 136, no. 5, pp. 759-764
Archer, S.D. Stelfox-Widdicombe, C.E., Malin, G., Burkill, P.H. 2003. Is Dimethyl sulfide production related to microzooplankton herbivory in the southern North Sea? J. Plankton Research Vol. 25, no. 2, pp 235-242Hay, M.E., Kubanek, J. 2002 Community and ecosystem level consequences of chemical cues in the plankton. Journal of Chemical Ecology Vol 28, no. 20, pp 2001-2016
back to article
Wolfe, G.V., Steinke, M., Kirst, G.O. 1997. Grazing activated chemical defence in a unicellular marine alga. Nature vol. 387, no. 6636, pp. 894-897Wolfe, G.V. 2000. The chemical defense ecology of marine unicellular plankton: constraints, mechanisms, and impacts. Biol. Bull. 198:225-244
Van Alstyne, K.L., Wolfe, G.V., Freidenburg, T.L, Neill, A., Hicken, C. 2001. Activated defense systems in marine macroalgae: evidence for an ecological role for DMSP cleavage. Mar. Ecol. Prog. Ser.Vol. 213, pp 53-65
Ibid.
Nevitt, G.A. 2000. Olfactory foraging by Antarctic Procellariiform seabirds: life at high Reynolds numbers. Biol. Bull,198:245-253
Ibid.
back to article
Nevitt, G.A., Velt, R.R., Karelva, P. 1995. Dimethyl sulphide as a foraging cue for Antarctic Procellariiform seabirds. Nature Vol. 376, pp 680-682
Ibid.
Berresheim, H., F. L. Eisele, D. J. Tanner, L. M. McInnes, D. C. Ramseybell and D. S. Covert 1993, Atmospheric Sulfur Chemistry and Cloud Condensation Nuclei (Ccn) Concentrations over the Northeastern Pacific Coast. Journal of Geophysical Research-Atmospheres98 (D7): 12701-12711
Charlson, R.J. Lovelock, J.E., Andreae, M.O., and Warren, S.G. 1987. Oceanic phytoplankton, atmospheric sulfur, cloud albedo and climate: a geophysiological feedback. Nature326;655-661
http://asd-www.larc.nasa.gov/ceres/brochure/sci_priorities.html(Science Priorities, CERES, Clouds and the Earths Radiant Energy System, NASA Langley Research Center)
back to article
Kulmala, M. Laaksonen, A., Korhonen, P., Vesala, T. and Ahonen, T. 1993. The effect of atmospheric nitric acid vapor on cloud condensation nucleus activation, Journal of Geophysical Research98:22, 949-22,958
Lovelock, J. E. 1979. Gaia: A New Look at Life on Earth. Oxford University Press
Sciare, J., Mihalopoulos, N. and Dentener, F.J. 2000. Interannual variability of atmospheric dimethylsulfide in the southern Indian Ocean. Journal of Geophysical Research105: 26,369-26,377
Plankton may influence climate change says UCSB scientist
Plankton appear to play a major role in regulating the global climate system, according to new research
David Siegel, professor of geography at the University of California, Santa Barbara, and director of the Institute for Computational Earth System Science, made the discovery with his former Ph.D. student Dierdre Toole, who is now based at Woods Hole Oceanographic Institute. In an article in the May 6 issue of the journal Geophysical Research Letters, the scientists explain their research in the Sargasso Sea, approximately 50 miles southeast of the island of Bermuda. Siegel’s research group has been making observations at this location since 1992. Phytoplankton are tiny, single-celled floating plants. They inhabit the upper layers of any natural body of water where there is enough light to support photosynthetic growth. They are the base of the ocean’s food web, and their production helps to regulate the global carbon cycle. They also contribute to the global cycling of many other compounds with climate implications. One of these compounds is a volatile organic sulfur gas called dimethyl sulfide or DMS. Scientists had previously theorized that DMS is part of a climate feedback mechanism, but until now there had been no observational evidence illustrating how reduced sunlight actually leads to the decreased ocean production of DMS. This is the breakthrough in Toole and Siegel’s research. They describe how the cycle begins when the ocean gives off DMS to the lower atmosphere. In the air, DMS breaks down into a variety of sulfur compounds that act as cloud-condensing nuclei, leading to increased cloudiness. With more clouds, less sunlight reaches the Earth and the biological processes which produce DMS are reduced. According to their research, it appears that phytoplankton produce organic sulfur compounds as a chemical defense from the damaging effects of ultraviolet radiation and other environmental stresses, in much the same way as our bodies use vitamins E and C to flush out molecules that cause cellular damage. Siegel and Toole found that ultraviolet radiation explained almost 90 percent of the variability in the biological production of DMS. They showed that summertime DMS production is "enormous," and that the entire upper layer of DMS content is replaced in just a few days. This demonstrates a tight link between DMS and solar fluxes. "The significance of this work is that it provides, for the first time, observational evidence showing that the DMS-anti-oxidant mechanism closes the DMS-climate feedback loop," said Siegel. "The implications are huge. Now we know that phytoplankton respond dramatically to UV radiation stresses, and that this response is incredibly rapid, literally just days." He explained that the findings give new impetus for scientists to re-examine the DMS-climate feedback hypothesis. And the DMS-climate feedback may also play out under possible global warming and climate change scenarios. As the Earth’s ozone shield thins and greenhouse gases increase, higher ultraviolet radiation will reach the surface layer of the oceans. The findings indicate that phytoplankton will then produce more DMS in response to this increased ultraviolet radiation, causing increasing cloudiness and mitigating the effects of global warming. However, Siegel is careful to note that while the process may mitigate global warming it will not reverse the trend. The project was funded by NASA. NASA’s Earth Science Enterprise is dedicated to understanding the Earth as an integrated system and applying Earth System Science to improve prediction of climate, weather, and natural hazards using the unique vantage point of space.
Note: David Siegel can be reached at 805-893-4547 or by e-mail at davey@icess.ucsb.edu.
Gail Gallessich Quelle: EurekAlert! Weitere Informationen: www.ucsb.edu/
Thursday, October 2, 2008
Probe into rising ocean acidity
The UK's Royal Society has launched an investigation into the rising acidity of the world's oceans due to pollution from the greenhouse gas carbon dioxide.
The change could have catastrophic consequences for marine life.
Oceans mop up carbon dioxide from the atmosphere, lowering the water's pH value - an effect that may be exacerbated by burning of fossil fuels.
Scientists on the working group are due to publish an initial report into the phenomenon by early next year.
Oceans mop up carbon dioxide from the atmosphere, lowering the water's pH value - an effect that may be exacerbated by burning of fossil fuels.
Scientists on the working group are due to publish an initial report into the phenomenon by early next year.
The investigation by the Royal Society, the UK national academy of science, will probe the potential impact of this rising ocean acidity on marine life - which at present is largely unknown.
Increasing use of fossil fuels means more carbon dioxide is going into the air. Most of it will eventually be absorbed by seawater, where it reacts to form carbonic acid.
The Intergovernmental Oceanographic Commission reports that some 20-25 million tonnes of carbon dioxide are being added to the oceans each day.
Researchers believe such dramatic changes in the carbon dioxide system in surface waters have not been observed for more than 20 million years of Earth history.
Delicate balance
Experts currently predict that if this trend continues, ocean pH could fall by as much as 0.4 units by the year 2100.
"The thing about acidification is that it is happening at the same time that the oceans are warming, so organisms are going to have to deal with two major changes," working group member Dr Carol Turley of Plymouth Marine Laboratory told BBC News Online.
"Whether they balance each other, or whether they double or triple up is not known."
Increasing use of fossil fuels means more carbon dioxide is going into the air. Most of it will eventually be absorbed by seawater, where it reacts to form carbonic acid.
The Intergovernmental Oceanographic Commission reports that some 20-25 million tonnes of carbon dioxide are being added to the oceans each day.
Researchers believe such dramatic changes in the carbon dioxide system in surface waters have not been observed for more than 20 million years of Earth history.
Delicate balance
Experts currently predict that if this trend continues, ocean pH could fall by as much as 0.4 units by the year 2100.
"The thing about acidification is that it is happening at the same time that the oceans are warming, so organisms are going to have to deal with two major changes," working group member Dr Carol Turley of Plymouth Marine Laboratory told BBC News Online.
"Whether they balance each other, or whether they double or triple up is not known."
Scientists fear this increasing acidification could have a particularly detrimental effect on corals and sea creatures with hard shells.
Increasing acidity reduces the availability of calcium carbonate from the water - which the creatures rely on to produce their hard skeletons. Juvenile organisms could be most susceptible to these changes.
Acidification may also directly affect the growth and reproduction rates of fish, as well as affecting the plankton populations which they rely on for food, with potentially disastrous consequences for marine food webs.
In addition, nutrient concentrations in surface waters of high-latitude regions are likely to fall, subsurface waters become less oxygenated, and phytoplankton will experience increased exposure to sunlight.
This could affect multiple marine species and change the composition of biological communities in ways that are not yet understood.
Increasing acidity reduces the availability of calcium carbonate from the water - which the creatures rely on to produce their hard skeletons. Juvenile organisms could be most susceptible to these changes.
Acidification may also directly affect the growth and reproduction rates of fish, as well as affecting the plankton populations which they rely on for food, with potentially disastrous consequences for marine food webs.
In addition, nutrient concentrations in surface waters of high-latitude regions are likely to fall, subsurface waters become less oxygenated, and phytoplankton will experience increased exposure to sunlight.
This could affect multiple marine species and change the composition of biological communities in ways that are not yet understood.
According to research by Christopher Sabine of the US National Oceanographic and Atmospheric Administration (NOAA) the ocean has taken up approximately 120 billion metric tonnes of carbon generated by human activities since 1800.
"The same pollution that we believe is heating the world's oceans through global warming is also altering their chemical balance," Professor John Raven, chair of the working group, said.
"This study will look at what impact increased acidity levels might have on marine life and re-emphasise the urgent need to respond to the spectre of climate change, an issue identified by the UK Government as a priority for its Presidency of G8 in 2005."
"The same pollution that we believe is heating the world's oceans through global warming is also altering their chemical balance," Professor John Raven, chair of the working group, said.
"This study will look at what impact increased acidity levels might have on marine life and re-emphasise the urgent need to respond to the spectre of climate change, an issue identified by the UK Government as a priority for its Presidency of G8 in 2005."
The issue was highlighted last year with a research paper published in the prestigious journal Nature by Ken Caldeira and Michael Wickett of the Lawrence Livermore National Laboratory in California, US. Dr Caldeira is also a member of the Royal Society working group.
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