Today, the BBC and the Telegraph, among others, discussed the proposal of James Lovelock of Oxford and Chris Rapley, former head of the British Antarctic Survey, to reduce CO2 levels by pumping it into the deep ocean. Note that this is a type of carbon sequestration.
Lovelock and Rapley believe this action is necessary because climate change is progressing rapidly and current programs to reduce greenhouse gas emissions won’t to the job fast enough. However, as some of the commentary on this idea, and a related op-ed piece in the New York Times note this approach is not without risk. Disturbingly, they promote an idea that will increase the acid level of the ocean, when acidification is already leading to the death of coral reefs and shellfish. This idea may simply substitute one problem for another.
From the Telegraph:
[Lovelock and Rapley] believe the answer lies in the oceans, which transport much more heat than the atmosphere and, covering more than 70 per cent of the Earth’s surface.
They propose that vertical pipes some 10 metres across be placed in the ocean, such that wave motion would pump up cool water from 100-200 metres depth to the surface, moving nutrient-rich waters in the depths to mix with the relatively barren warm waters at the ocean surface.
This would fertilise algae in the surface waters and encourage them to bloom, absorbing carbon dioxide greenhouse gas while also releasing a chemical called dimethyl sulphide that is know to seed sunlight reflecting clouds.
“Such an approach may fail, perhaps on engineering or economic grounds”, they say, adding that the effects on the acidity of the ocean also have to be factored in.
In an earlier post, we discussed the dangers posed by rising acid levels in the ocean:
But there are side effects to our love affair with CO2 that are not often mentioned. In fact, whether the earth cools or warms is absolutely irrelevant to these effects. I repeat: Absolutely irrelevant.
One of the most startling effects is the acidification of the oceans. Since 1750, the oceans have become increasingly acidic. In the oceans, CO2 forms carbonic acid, a serious threat to the base of the food chain, especially on shellfish of all sizes. Carbonic acid dissolves calcium carbonate, an essential component of any life form with an exoskeleton. In short, all life forms with an exoskeleton are threatened: shell fish, an important part of the food chain for many fish; coral reefs, the habitat of many species of fish….
The formation of carbonic acid does not depend upon temperature. Whether the oceans warm or cool is irrelevant. Of concern only is the amount of CO2 that enters the oceans….
According to one estimate, between 1750 and 1994, oceans absorbed 118 billion tons of CO2—and we were just starting serious CO2 production. As anyone with a fish tank knows, as the Ph falls, the water becomes more acidic. Fish life becomes more and more problematical.
This absorption has made the world’s oceans significantly more acidic since the beginning of the industrial revolution. Research published last year by Mark Jacobson, an assistant professor of civil and environmental engineering at Stanford University, indicated that between 1751 and 2004 surface ocean pH dropped from approximately 8.25 to 8.14. James Orr of the Climate and Environmental Sciences Laboratory further estimated that ocean pH levels could fall another 0.3 – 0.4 units by 2100.
In fact, by 2050,
…there may be too little carbonate for [in the Pacific] organisms to form shells as soon as 2050.
Since 1990 alone, Ph levels in the Pacific have dropped .0025. Such a drop may not seem significant until one understands Ph levels.
Today, in a New York Times op-ed, Viaclav Havel points out one of the fallacies of reasoning like Lovelock’s and Rapley’s: that extreme measures to counter greenhouse gas emissions also move the equilibrium:
The effects of possible climate changes are hard to estimate. Our planet has never been in a state of balance from which it could deviate through human or other influence and then, in time, return to its original state. The climate is not like a pendulum that will return to its original position after a certain period. It has evolved turbulently over billions of years into a gigantic complex of networks, and of networks within networks, where everything is interlinked in diverse ways.
Its structures will never return to precisely the same state they were in 50 or 5,000 years ago. They will only change into a new state, which, so long as the change is slight, need not mean any threat to life.
Larger changes, however, could have unforeseeable effects within the global ecosystem. In that case, we would have to ask ourselves whether human life would be possible. Because so much uncertainty still reigns, a great deal of humility and circumspection is called for.