[AI] Fwd: Article from The Hindu: Sent to you by Niranjan.B

Kalpana Kharade kkharade at gmail.com
Thu Jun 19 08:30:15 EDT 2008


Thanks. very informative indeed.
                Dr. Kalpana
----- Original Message ----- 
From: "niranjanraj urs" <niranjanursb at gmail.com>
To: <accessindia at accessindia.org.in>
Sent: Thursday, June 19, 2008 12:35 PM
Subject: [AI] Fwd: Article from The Hindu: Sent to you by Niranjan.B


> ---------- Forwarded message ----------
> From: thehindu at web1.hinduonnet.com
> Date: Thu, 19 Jun 2008 11:19:55 +0530
> Subject: Article from  The Hindu: Sent to you by Niranjan.B
> To:
>
> =============================================================
> This article has been sent to you by Niranjan.B ( niranjanursb at gmail.com )
> =============================================================
> Source: The Hindu
> (http://www.hinduonnet.com/2008/06/19/stories/2008061955591100.htm)
> Opinion
> -
> News Analysis
>   
>
> For a pilot project on deep sea storage of CO2
>
>
>
>
> Wallace S. Broecker
>
>
>
>
> One of the world’s leading climate scientists challenges
> Greenpeace’s opposition to storing CO2in the depth of the
> oceans.
>
>
>
>
> Most of us who are concerned about global warming agree that an
> important part of any strategy designed to stem the ongoing build-up
> of greenhouse gases in the atmosphere will be to capture and store
> CO2. Potential storage sites include spent oil fields, saline
> aquifers, layered basalts and the deep ocean.
>
> “Point pollution”
>
>
>
> While Greenpeace accepts the inevitability that CO2 will be captured
> and stored, it strongly opposes storage in the deep sea. As it is
> clear that virtually all the CO2 released to the atmosphere as a
> result of fossil fuel burning will ultimately find its way to the deep
> sea, its objection is focused on the “point pollution”
> created by purposeful injections of CO2. The fear is that such an
> activity will put at risk benthic biota — the community of
> creatures and plants in the deep sea — living in the vicinity of
> the injection sites.
> In February 2007, I contacted Bill Hare, a senior scientist at
> Greenpeace, asking him to reconsider his organisation’s stance
> against experiments to evaluate the environmental consequences of CO2
> injected into the deep sea. I pointed out that if marine disposal
> proves to be economically favourable, and if push comes to shove,
> forces more powerful than Greenpeace will probably intervene and deep
> sea disposal will commence without adequate testing and evaluation.
> Hare agreed to reconsider this matter in consultation with members of
> his and other like-minded organisations. In June 2007, he reported
> back that no change in policy would be made.
> What is known about deep ocean storage?
> First, in order to ensure that the injected CO2 has adequate time to
> mix throughout the deep sea, injection should be at depths greater
> than 3,500 metres — that is, the depth below which
> “liquid” CO2 becomes more dense than sea water.
> Experiments conducted by Peter Brewer, of the Monterey Bay Aquarium
> Research Institute, not only confirm that this is the case but also
> demonstrate that the CO2 injected rapidly reacts with sea water to
> form a solid clathrate, which is more dense than both liquid CO2 and
> sea water. Hence, the injected CO2 would end up on the sea floor as a
> slush. This would gradually dissolve, releasing the CO2 to the
> surrounding sea water, where it would react with the dissolved
> carbonate and borate ions to become chemically bound in the form of
> bicarbonate ion. As the concentration of carbonate and borate ions is
> small, the neutralisation would take place gradually as the CO2-rich
> sea water mixed into the surroundings.
>
>
> Prime taget for storage
>
>
>
> We know that, based on radiocarbon measurements, the residence time of
> water in the abyssal Atlantic is in the order of 200 years. For the
> Indian Ocean, it is about 800 years, and for the Pacific about 1,000
> years. As the deep Pacific has the largest volume, and is adjacent to
> earthquake-prone land areas where below-ground storage could not be
> safely done, it will be a prime target for storage.
> A conservative upper limit on the storage capacity of the deep
> Pacific would be to require that the CO2 concentration in the water
> returning to the surface not be allowed to exceed the concentration in
> cold surface water at equilibrium with the atmosphere. Were this the
> limit to be adopted, then the capacity of water deeper than 1,500
> metres in the Pacific would be about 480 gigatons of CO2, or about 130
> gigatons of carbon for each 100 parts per million rise in atmospheric
> CO2 content.
>
>
> Need for study
>
>
>
> We know enough to say with confidence that deep ocean disposal of CO2
> is certainly feasible, but unless small-scale pilot experiments are
> conducted, information necessary to assess the impact on the macro
> abyssal biota will remain obscure. The injections could be made from
> ships equipped for deep sea drilling, and if the CO2 were tagged with
> radiocarbon, its dispersal away from the sea floor clathrate pile
> could be sensitively monitored.
> Studies of the costs associated with ocean disposal would also be
> conducted. The CO2 would have to be sent through pipelines from its
> collection point to a port, where it would be loaded on tankers that
> would carry it to a floating ocean station, from which it would be
> piped to the abyss.
> Putting aside the opposition by the environmental community, ocean
> disposal will become a viable option only if the costs are competitive
> with those associated with storage in hyper-saline continental
> aquifers.
>
>
> Do the homework
>
>
>
> As any strategy designed to stem the build-up of greenhouse gases will
> have adverse environmental consequences, we must seek to minimise
> their impact. To the extent that we could capture and store CO2
> produced by fossil fuel burning, we would reduce the acidification of
> the surface ocean, and hence the additional stress on coral reef
> communities. To date, there is no indication that the projected rise
> in upper ocean CO2 content will have adverse impacts on fish. If so,
> assuming the limit described above were to be observed, then once
> spread through the deep sea, the injected CO2 would not adversely
> impact on benthic biota.
> However, I sympathise with those who claim that the benthic world is
> a fragile one. Hence, before we poke it with CO2, we should do our
> homework. Therefore, I challenge Greenpeace to relax its stand and
> allow a pilot project to proceed. — © Guardian Newspapers
> Limited, 2008
> (Wallace S. Broecker is the Newberry professor in the Department of
> Earth and Environmental Sciences at Columbia University, New York.)
>
>
>
>
>
>
>
>
>
>
>
>
> Copyright: 1995 - 2006 The Hindu
>
> Republication or redissemination of the contents of this screen are 
> expressly
> prohibited without the consent of  The Hindu
>
> To unsubscribe send a message to accessindia-request at accessindia.org.in 
> with the subject unsubscribe.
>
> To change your subscription to digest mode or make any other changes, 
> please visit the list home page at
>  http://accessindia.org.in/mailman/listinfo/accessindia_accessindia.org.in 





More information about the AccessIndia mailing list