The estuary of the Amazon River is (pictured in this satellite image) is one of the largest in the world.
Credit: NASA
PORTLAND, OREGON: Ocean acidification, caused by rising CO2 levels, is affecting not only coral reefs, but coastal ecosystems by changing everything from the ability of oysters to adhere to the riverbed to the extent of dead zones along the U.S. Pacific coast.
Ocean acidification is occurring because CO2 from the burning of fossil fuels is dissolving in the seas, creating a weak carbonic acid solution. Much of the attention on the problem so far has focussed on coral reefs, which are particularly vulnerable to changes in pH (see "Oceans of acid").
Combination of impacts
But riverine and other coastal environments may also be unusually vulnerable because they face a range of additional threats from problems such as pollution and variable levels of acidity and organic matter flowing into them, said Richard Feely, an oceanographer at the National Oceanic and Atmospheric Administration's Pacific Marine Environmental Laboratory in Seattle, USA.
"Each estuary is different [and]... in coastal ecosystems, we have to think about combined impacts," he said at a scientific meeting of the Coastal and Estuary Research Foundation in Portland, Oregon earlier this month.
Another danger is that coastal systems are highly variable. Adding the problem of acidification on top of their natural variability might push them over tipping points from which they cannot recover, added Burke Hales, an oceanographer at Oregon State University in Corvallis.
Spiralling out of control
On the Northwest coast of North America, for example, shifting winds can alternately draw deep, more acidic water up to the surface or pull less acidic surface waters into the bays. The result is that the bays can see rapid changes in acidity with changes in the weather.
"This natural variability is pushing these systems close to important thresholds, and the creeping changes that go along with that [from climate change and ocean acidification] might be enough to push these systems over that line," said Hales.
But, he added, "it's not all bad news." Upwelling waters from the deep may be acidic, but they also bring up a lot of nitrates. These can fertilise massive growth of phytoplankton, which form the basis of the coastal ecosystem.
Ocean Acidification
One good-sized undersea volcano can disgorge more acid-causing gases than ALL the man-made pollution on earth by orders of magnitude. Increased activity at the rift zones, especially in the Pacific, is the most likely cause of acidification and we can't do diddly squat about it.
So stop the "global warming" hysteria. We can't do much to change any of this. We are along for the ride and always have been.
Nature has the means (and routinely uses them) to counterbalance the exhaust fumes of volcanoes to say nothing of the puny contributions of man.
Ocean Acidification
Your logic doesn't make any sense. Since 'nature' has the capacity to destroy us at any given moment, we should not worry about us destroying ourselves?
We are now learning that past mass extinction events appear to be coupled with massive increases of CO2. Whatever the cause of the CO2 increases of the past, they may be responsible for wiping out 90% of marine life in the sea during the Permian mass extinction, 251 million years ago. Disruptions of the carbon cycle (increasing and decreasing atmospheric CO2) correlate with all past mass extinction events.
One difference between us and nature is that nature killed off all these species in time spans on the scale of thousands of years. We are disrupting the carbon cycle much faster on the scale of hundreds of years. We can't do much to change any of this? How about stop putting CO2 into the atmosphere. This would kill to birds with one stone: global warming and ocean acidification. We've survived without fossil fuels before, we could do it again. We are not idiots.
Ocean Acidification
I agree that nature can take care of our carbon output. The Earth has natural cycles of warming and cooling and we have been in a warming trend of over a thousand years. Commercial green houses pump carbon gas into their "green" houses to increase plant production. More carbon in the air will cause more plant life to absorb it.
Why do these articles never
Why do these articles never quote the actual PH? It seems that any changes in alkalinity is now called acidification, a word coined simply for climate alarmism.
Last I read the PH is about 8.2 on a logarithmic scale, bringing it down will require a lot of CO2 and with the oceans already containing 50 times more carbon than the atmosphere a tall order...