By Sandi Doughton
Climate models predicted it wouldn't happen until the end of the century.
So a team led by Seattle researchers was stunned to discover that vast swaths of acidified seawater already are showing up along the Pacific Coast as greenhouse-gas emissions upset the oceans' chemical balance.
In surveys from Vancouver Island to the tip of Baja California, reported Thursday in the online journal Science Express, the scientists found the first evidence that large amounts of corrosive water are reaching the continental shelf — the shallow sea margin where most marine creatures live.
Off Northern California, the acidified water was only four miles from shore.
"What we found ... was truly astonishing," said oceanographer Richard Feely, of the National Oceanic and Atmospheric Administration's (NOAA) Pacific Marine Environmental Laboratory in Seattle. "This means ocean acidification may be seriously impacting marine life on the continental shelf right now."
All along the coast, the scientists found regions where the water was acidic enough to dissolve the shells and skeletons of clams, corals and many of the tiny creatures at the base of the marine food chain. Acidified water also can kill fish eggs and a wide range of marine larvae.
"Entire marine ecosystems are likely to be affected," said co-author Debby Ianson, an oceanographer at Fisheries and Oceans Canada.
Though it hasn't received as much attention as global warming, ocean acidification is a flip side of the same phenomenon. The increase in atmospheric carbon dioxide from power plants, factories and cars that is raising temperatures worldwide also is to blame for the increasing acidity of the world's oceans.
Normally, seawater is slightly alkaline. When carbon dioxide from the atmosphere dissolves into the water, it forms carbonic acid — the weak acid that helps give soda pop its tang. The process also robs the water of carbonate, a key ingredient in the formation of calcium carbonate shells.
Since the Industrial Revolution, when humans began pumping massive amounts of carbon dioxide into the atmosphere, Feely estimates the oceans have absorbed 525 billion tons of the man-made greenhouse gas — about one-third of the total released during that period.
By keeping some of the carbon dioxide out of the atmosphere, the oceans have blunted the temperature rise due to global warming. But they've suffered for that service, with a more than 30-percent increase in acidity.
The acidified water does not pose a direct threat to people. "We're not talking battery acid here," said co-author Burke Hales, an oceanographer at Oregon State University.
On the pH scale, which measures acidity, strongly alkaline materials such as oven cleaner measure about 13. Hydrochloric acid has a pH of 1. Seawater usually measures around 8.1. The most acidic water the scientists found off the Pacific Coast measured 7.6 on the pH scale. The numerical difference may seem slight, but it represents a threefold increase in acidity, Hales said.
Until now, researchers believed the most acidified water was confined to the deep oceans. Cold water, which holds more carbon dioxide, sinks. Deep waters also are naturally high in carbon dioxide, which is a byproduct of the decay of plankton.
Feely and his NOAA colleague Christopher Sabine previously have shown that zones of acidified water are growing and moving closer to the surface as the oceans absorb more man-made carbon dioxide.
During surveys on the Pacific Coast last year, a team including Feely and Sabine discovered the natural upwelling that occurs along the West Coast each spring and early summer is pulling the acidified water onto the continental shelf.
"I think this is a red flag for us, because it's right at our doorstep on the West Coast," said Victoria Fabry, a biological oceanographer at California State University, San Marcos, who was not involved with the study. "It's telling us that we really need more monitoring to figure out what's going on."
Climate scientist Ken Caldeira, of the Carnegie Institution at Stanford University, said the finding underscores the limitations of computer models.
"This is another example where what's happening in the natural world seems to be happening much faster than what our climate models predict," he said.
And there's worse to come, the scientists warn.
A network of currents shuffles ocean water around the globe. The acidified water upwelling along the coast today was last exposed to the atmosphere about 50 years ago, when carbon-dioxide levels were much lower than they are now.
That means the water that will rise from the depths over the coming decades will have absorbed more carbon dioxide and will be even more acidic.
"We've got 50 years worth of water that's already left the station and is on its way to us," Hales said. "Each one of those years is going to be a little bit more corrosive than the one before."
By Borzou Daragahi
BEIRUT -- Lebanon's long-simmering political crisis lurched deeper into violent civil conflict Thursday as bands of Shiite and Sunni gunmen battled in the streets for a second day and politicians took to the airwaves to denounce each other for pushing the country toward war.
Explosions and bursts of gunfire rattled central Beirut as groups allied with the Hezbollah-led opposition and the United States-backed government fired machine guns, assault rifles and grenade launchers at each other and into the air, apparently in shows of strength. The deep thuds of occasional mortar fire shook the ground as night fell.
Throughout the day, panicked civilians scurried for cover or loaded up on basic supplies, emptying supermarket shelves of frozen meats. Gunmen had blocked roads to the country's only international airport as well as the main highways to Damascus, the Syrian capital, and to southern Lebanon, in effect placing the capital under siege.
Lebanese news sources said at least four people were killed in fighting Thursday and a female bystander died of injuries sustained in the previous day's clashes. But information was scant as paramedics and security officials avoided entering areas of intense fighting that witnesses said resembled the level of the civil war that engulfed the country from 1975 to 1990.
By late night, government allies were calling for "dialogue" with the Shiite group Hezbollah, even as fighting continued and allegations mounted that its militiamen were raiding homes and offices of government supporters.
"We are trapped in our homes," one Sunni militiaman aligned with the pro-government Future movement said Thursday night, speaking by telephone from his central Beirut home. He spoke on condition of anonymity. "They shot at my building and at my car. We are trying to call the army to protect us and hoping we won't be taken from our homes but they will know sooner or later where we live."
The violence comes amid heightened regional tensions between the U.S. and Saudi Arabia, which strongly back the government, and Iran and Syria, which support Hezbollah and the opposition. In Lebanon, as well as the Palestinian territories and Iraq, the U.S. has begun increasing pressure on Iranian allies.
U.S. officials blamed Hezbollah for the unrest in Lebanon.
"Hezbollah needs to make a choice: Be a terrorist organization or be a political party, but quit trying to be both," U.S. national security council spokesman Gordon Johndroe said Thursday. "They need to stop their disruptive activities now."
Tensions escalated Tuesday after the government voted to outlaw Hezbollah's communications network, which the group was allegedly expanding, and sack the Hezbollah-allied head of security at the international airport, who had allegedly begun harassing visitors believed to have political ties to the government.
The fiercest battles broke out after a televised speech Thursday afternoon by Hezbollah's chief, Sheik Hassan Nasrallah.
He said the Cabinet's decision to declare the group's fiber-optic system illegal was tantamount to a declaration of war and put the government squarely in the camp of Hezbollah's enemies, Israel and the United States, which consider it a terrorist organization.
"This decision is first of all a declaration of war and the launching of war by the government . . . against the resistance and its weapons for the benefit of America and Israel," Nasrallah told reporters via teleconference.
"The communications network is the significant part of the weapons of the resistance," said Nasrallah. "I had said that we will cut the hand that targets the weapons of the resistance. . . . Today is the day to fulfill this decision."
The celebratory gunfire that punctuates the end of political speeches here escalated into armed confrontations and sustained gunfire that continued past midnight.
Saad Hariri, leader of Lebanon's Sunni community and head of the parliamentary majority, appeared on television saying the government would ask the army to enforce the decision to uproot the telecommunications network and remove the head of airport security.
"You say you don't want Sunni-Shiite strife and we don't want this to happen either," he said.
An analyst called the proposal a "small retreat" by Hariri's camp, because the Lebanese army lacks the strength or unity to confront Hezbollah or any other of the country's major political groups. The army also coordinates closely with Hezbollah on security matters and has affirmed its support for "resistance" to Israel, which has repeatedly invaded and occupied Lebanon over the last several decades.
Supported by Iran and Syria, Hezbollah operates as a state within a state, with strongholds in southern and western Lebanon and Beirut's southern suburbs. Its armed wing fought Israel to a standstill in the summer of 2006. Hezbollah claimed victory in that conflict, but the war upset Lebanon's fragile sectarian balance and precipitated a political crisis that has left the country without a president since November.
Government supporters said they were angered by what they considered Hezbollah's attempts to exploit the crisis to expand its domestic surveillance and communications abilities, as well as its armed capacity.
"Hezbollah is launching a gradual coup against the state of Lebanon," said Walid Jumblatt, leader of Lebanon's Druze community and a staunch government supporter.
By Borzou Daragahi
BEIRUT -- Lebanon's long-simmering political crisis lurched deeper into violent civil conflict Thursday as bands of Shiite and Sunni gunmen battled in the streets for a second day and politicians took to the airwaves to denounce each other for pushing the country toward war.
Explosions and bursts of gunfire rattled central Beirut as groups allied with the Hezbollah-led opposition and the United States-backed government fired machine guns, assault rifles and grenade launchers at each other and into the air, apparently in shows of strength. The deep thuds of occasional mortar fire shook the ground as night fell.
Throughout the day, panicked civilians scurried for cover or loaded up on basic supplies, emptying supermarket shelves of frozen meats. Gunmen had blocked roads to the country's only international airport as well as the main highways to Damascus, the Syrian capital, and to southern Lebanon, in effect placing the capital under siege.
Lebanese news sources said at least four people were killed in fighting Thursday and a female bystander died of injuries sustained in the previous day's clashes. But information was scant as paramedics and security officials avoided entering areas of intense fighting that witnesses said resembled the level of the civil war that engulfed the country from 1975 to 1990.
By late night, government allies were calling for "dialogue" with the Shiite group Hezbollah, even as fighting continued and allegations mounted that its militiamen were raiding homes and offices of government supporters.
"We are trapped in our homes," one Sunni militiaman aligned with the pro-government Future movement said Thursday night, speaking by telephone from his central Beirut home. He spoke on condition of anonymity. "They shot at my building and at my car. We are trying to call the army to protect us and hoping we won't be taken from our homes but they will know sooner or later where we live."
The violence comes amid heightened regional tensions between the U.S. and Saudi Arabia, which strongly back the government, and Iran and Syria, which support Hezbollah and the opposition. In Lebanon, as well as the Palestinian territories and Iraq, the U.S. has begun increasing pressure on Iranian allies.
U.S. officials blamed Hezbollah for the unrest in Lebanon.
"Hezbollah needs to make a choice: Be a terrorist organization or be a political party, but quit trying to be both," U.S. national security council spokesman Gordon Johndroe said Thursday. "They need to stop their disruptive activities now."
Tensions escalated Tuesday after the government voted to outlaw Hezbollah's communications network, which the group was allegedly expanding, and sack the Hezbollah-allied head of security at the international airport, who had allegedly begun harassing visitors believed to have political ties to the government.
The fiercest battles broke out after a televised speech Thursday afternoon by Hezbollah's chief, Sheik Hassan Nasrallah.
He said the Cabinet's decision to declare the group's fiber-optic system illegal was tantamount to a declaration of war and put the government squarely in the camp of Hezbollah's enemies, Israel and the United States, which consider it a terrorist organization.
"This decision is first of all a declaration of war and the launching of war by the government . . . against the resistance and its weapons for the benefit of America and Israel," Nasrallah told reporters via teleconference.
"The communications network is the significant part of the weapons of the resistance," said Nasrallah. "I had said that we will cut the hand that targets the weapons of the resistance. . . . Today is the day to fulfill this decision."
The celebratory gunfire that punctuates the end of political speeches here escalated into armed confrontations and sustained gunfire that continued past midnight.
Saad Hariri, leader of Lebanon's Sunni community and head of the parliamentary majority, appeared on television saying the government would ask the army to enforce the decision to uproot the telecommunications network and remove the head of airport security.
"You say you don't want Sunni-Shiite strife and we don't want this to happen either," he said.
An analyst called the proposal a "small retreat" by Hariri's camp, because the Lebanese army lacks the strength or unity to confront Hezbollah or any other of the country's major political groups. The army also coordinates closely with Hezbollah on security matters and has affirmed its support for "resistance" to Israel, which has repeatedly invaded and occupied Lebanon over the last several decades.
Supported by Iran and Syria, Hezbollah operates as a state within a state, with strongholds in southern and western Lebanon and Beirut's southern suburbs. Its armed wing fought Israel to a standstill in the summer of 2006. Hezbollah claimed victory in that conflict, but the war upset Lebanon's fragile sectarian balance and precipitated a political crisis that has left the country without a president since November.
Government supporters said they were angered by what they considered Hezbollah's attempts to exploit the crisis to expand its domestic surveillance and communications abilities, as well as its armed capacity.
"Hezbollah is launching a gradual coup against the state of Lebanon," said Walid Jumblatt, leader of Lebanon's Druze community and a staunch government supporter.
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