Some days when there is news like this, I feel like giving up all hope ... for future generations especially.
Oceans acidifying at unprecedented speed
by Michael Marshall, NewScientist.com -- 01 March 2012
Humanity's greenhouse gas emissions may be acidifying the oceans at a faster rate than at any time in the last 300 million years. The sheer speed of change means we do not know how severe the consequences will be.
As well as warming the planet, carbon dioxide seeps into the oceans and forms carbonic acid. As a result the water becomes more acidic.
The pH is currently dropping by about 0.1 per century. This ocean acidification harms organisms such as corals that rely on dissolved carbonate to make their shells. It also disrupts behaviour in some animals.
[...]
Time-series of bleached coral (Colpophyllia natans) at Coral Gardens, Florida Reef Tract. (A) Prebleaching (August 11, 2005). (B) Bleached (September 6, 2005). (C) Nearly recovered (November 9, 2005). (D) Recovered with normal pigmentation (March 2, 2006). (Photo courtesy of the Proceeding of the National Academy of Sciences)
Image Source: Rosenstiel School of Marine and Atmospheric Science
Coral bleaching in Maldives, Indian Ocean Photo: ALAMY
Image Source: telegraph.co.uk
It's not as bad as it seems, when you dig into the numbers -- it's worse.
Dang those logarithmic scales ...
Study: Oceans Acidifying Faster Than They Have in Past 300 Million Years
by Dave Levitan, onearth.org -- March 1, 2012
[...]
In a study published today in the journal Science, researchers compared the current rates of ocean change to other major acidification events going back 300 million years, and what they found is shocking: never in that long period did the ocean pH fall as rapidly as it is falling right now (lower pH means higher acidity). Ocean pH has already dropped 0.1 units to 8.1 -- it is a logarithmic scale, meaning the drop represents about a 30 percent change in acidity. Within another hundred years, it could drop to 7.8.
At this level, coral, mollusks, and many other creatures will be unlikely to survive. Increased CO2 entering the oceans depletes the carbonate ions that these animals need to make their shells and reefs.
[...]
When it comes to the oceans, though, "something drastic" might not even be enough. The rise in acidity is likely to continue apace for some time even if we were to stop emitting all CO2 right now. The fact that we're outpacing even the great extinction events of the last 300 million years suggests that we are indeed in the midst of the sixth such event in the planet's history. As disturbing as it is, there is a decent chance that for huge chunks of the world's marine life, it is already too late.
"I do not think there is much hope to reduce the rate of acidification," [Bärbel] Hönisch said in an email. "Even if we stopped producing CO2 now, the concentration in the atmosphere would remain high for a long time, unless we find an efficient and cost-effective way to reduce atmospheric CO2." This is not, though, a reason to give up trying, she added. [...]
Well that study's author has not entirely abandoned hope. Afterall there is a Carbon Cycle at work. It works on some huge scales as well.
The Ocean Carbon Cycle
Harvard Magazine -- November-December 2002
Of all the carbon dioxide (CO2) emitted into the atmosphere, one quarter is taken up by land plants, another quarter by the oceans. Understanding these natural mechanisms is important in forecasting the rise of atmospheric CO2 because even though plants and bodies of water now absorb surplus greenhouse gas, they could become new trouble spots. The ocean absorbs CO2 from the atmosphere in an attempt to reach equilibrium by direct air-to-sea exchange. This process takes place at an extremely low rate, measured in hundreds to thousands of years. However, once dissolved in the ocean, a carbon atom will stay there, on average, more than 500 years, estimates Michael McElroy, Butler professor of environmental science.
[...]
The Oceans can be a Carbon Sink, except those Phytoplankton can be quite fussy about where and when they will
bloom. Sometimes they need a kick start, like a dust storm from the Sahara to give them the Iron fertilizer they need. And they need lots of light and other upwelling nutrients too.
Climate and the Carbon Cycle
earthobservatory.nasa.gov
The Earth Observatory is part of the EOS Project Science Office
located at NASA Goddard Space Flight Center
[...]
Through photosynthesis, phytoplankton consume carbon dioxide on a scale equivalent to forests and other land plants. Some of this carbon is carried to the deep ocean when phytoplankton die, and some is transferred to different layers of the ocean as phytoplankton are eaten by other creatures, which themselves reproduce, generate waste, and die.
Worldwide, this “biological carbon pump” transfers about 10 gigatonnes of carbon from the atmosphere to the deep ocean each year. Even small changes in the growth of phytoplankton may affect atmospheric carbon dioxide concentrations, which would feed back to global surface temperatures.
Phytoplankton are responsible for most of the transfer of carbon dioxide from the atmosphere to the ocean. Carbon dioxide is consumed during photosynthesis, and the carbon is incorporated in the phytoplankton, just as carbon is stored in the wood and leaves of a tree. Most of the carbon is returned to near-surface waters when phytoplankton are eaten or decompose, but some falls into the ocean depths. (Illustration adapted from A New Wave of Ocean Science, U.S. JGOFS.)
Like I said, some days when there is news like this, I feel like giving up hope ... especially for future generations.
It's not like we have oceans of time, to solve this CO2 exchange problem. Especially when we are breaking records on the Million-of-Years time scales.
We might need a new measure of IQ before too long? Some sort of Planetary IQ.
Sounds like a good idea to me.