For a start, oceans provide 12% of the global food supply. Losing all that
could be the tipping point on its own, as a starving society unravels into
a vicious circle of conflict, de-industrialisation and de-urbanisation.
However, a far more serious concern is the change in the oceans which would
lead to them becoming sterilised. Likely, an ocean anoxic event is the
precursor event.

As I understand it, the Great Dying (P-T extinction) provides an analogue.
Anoxic oceans were linked with a mass extinction of land biodiversity. I
understand that a proposed mechanism for this is the creation of an
atmosphere laden with H2S and lacking a functioning ozone layer.

That's wouldn't be promising for the Chicken McNugget supply.

A
 On Jun 8, 2013 10:01 AM, "Ken Caldeira" <[email protected]>
wrote:

> Andrew,
>
> Please respond to what I said and not what you imagine I said.
>
> The issue has to do with a hypothetical case of sterilization of the
> oceans. There was no reference to climate change in my statement.
>
> I challenge anyone to construct a plausible causal chain that would lead
> from sterilization of the oceans to downfall of human civilization.
>
> This is not an expression of my values, this is an expression of my
> scientific understanding.
>
> Let all realize that I spend a large chunk of my time trying to
> investigate and protect human threats to ocean ecosystems.
>
> *This Scientist Aims High to Save the World's Coral Reefs*
>
> http://www.npr.org/player/v2/mediaPlayer.html?action=1&t=1&amp;islist=false&id=176344300&m=178462367<http://www.npr.org/player/v2/mediaPlayer.html?action=1&t=1&islist=false&id=176344300&m=178462367>
> (Aired Monday, 4/22 on NPR's All Things Considered; 7 minutes, 49 seconds)
>
> Best,
>
> Ken
>
> On Saturday, June 8, 2013, Andrew Lockley wrote:
>
>> In my view, history provides the best guide to the future.
>>
>> Civilisations are not long lived at the best of times, and their messy
>> and painful demise is usually accompanied by minor climate disruption.
>>
>> The more complex the civilisation, the less robust it is, as there is a
>> greater interconnectedness, and hence a greater ability to transmit shocks
>> through the system. To further explain : our ancestors would not have heard
>> about an antipodean earthquake, whereas now such a tremor can send markets
>> into meltdown in minutes.
>>
>> The idea that despite this much more vulnerable society, the American
>> middle class will survive the worst climate change in human history without
>> disruption to the Chicken McNugget supply, or to the ability of Hollywood
>> to produce Game of Thrones, is completely bizarre.
>>
>> Someone, somewhere will likely be eating a piece of battered chicken
>> meat. Someone, somewhere will probably still have a working digital camera
>> and some kind of transmission equipment . This does not equate to an
>> uninterrupted experience for the US middle class.
>>
>> A
>>  On Jun 8, 2013 8:42 AM, "Emily L-B" <[email protected]> wrote:
>>
>> **
>> Hi all, I'd propose you put this hypothesis to Dan Laffolley (you can
>> google him).
>> There are so many responses to this I am overwhelmed and can't respond
>> coherently. Apart from anything else, my understanding is that decay of
>> ocean matter would release noxious gases. So while there may be O2, it may
>> be polluted.
>> Best wishes,
>> Emily.
>> Sent from my BlackBerry
>> ------------------------------
>> *From: * Ken Caldeira <[email protected]>
>> *Sender: * [email protected]
>> *Date: *Sat, 8 Jun 2013 15:05:06 +0800
>> *To: *[email protected]<[email protected]>
>> *ReplyTo: * [email protected]
>> *Cc: *[email protected]<[email protected]>
>> *Subject: *[geo] The Caldeira "If you Sterilize the Ocean We'd Still
>> Have Chicken McNuggets Hypothesis" questioned by Ocean expert
>>
>> David,
>>
>> The residence time of oxygen in the atmosphere + ocean + biosphere with
>> respect to the lithosphere is millions of years.
>>
>> There are about 4 x 10 ** 19 mol of O2 in the atmosphere. The rate of
>> removal of this O2 by organic carbon weathering is about 4 x 10 ** 12 mol
>> per year.  I am not sure about pyrite oxidation and so on but you can check
>> out the attached paper for an entree into the literature.
>>
>> In any case, the 1000 year number you cite is not based on any reliable
>> literature value. A better guess might be that we would have breathable
>> oxygen on the order of a million years if you eliminated all life on land
>> and sea.  If life were eliminated in the oceans only, I don't know of
>> anything that would impede our ability to eat Chicken McNuggets and watch
>> TV indefinitely.
>>
>> Let me make it clear that I value life in the oceans quite highly and do
>> not at all like Chicken McNuggets.  (For some reason, nutters on the web
>> think that you can't discuss anything unless you are advocating actually
>> doing it.)
>>
>> Best,
>>
>> Ken
>>
>> On Saturday, June 8, 2013, David Lewis wrote:
>>
>> During the Q&A after his 2012 AGU talk entitled "*Ocean Acidification:
>>  Adaptive Challenge or Extinction Threat?*", Ken Caldeira said:  "I
>> actually think* if you sterilize the ocean*, yes vulnerable people would
>> be hurt, poor people would be hurt, but that* we'd still have Chicken
>> McNuggets and TV shows and basically we'd be OK* "  A video of Ken's
>> entire talk is* available 
>> here*<http://fallmeeting.agu.org/2012/events/gc44c-special-lecture-in-ocean-acidification-consequences-of-excess-carbon-dioxide-in-the-marine-environment-video-on-demand/>.
>>  He lays out the McNugget/Ocean Sterilization hypothesis starting at *minute
>> 50:20*.
>>
>> This seemed to be Ken's answer to the question he posed in his subtitle,
>> i.e. is homo sapiens facing a threat of extinction as a result of any
>> particular odd behavior the species is engaged in at the moment such as
>> carelessly dumping waste gases into the atmosphere which are changing the
>> chemistry of the global ocean?
>>
>> Callum Roberts, a scientist who studies the impact of human activity on
>> marine ecosystems, addressed an audience at the University of Sydney this
>> year where he discussed the many problems human activity is causing life in
>> the oceans.  He interrupted his litany of woe briefly to tell the audience
>> of some "*good news*" he had:  "even if all the ocean's primary
>> productivity were shot down tomorrow,* it will still be a long time
>> before we suffocate *because there's plenty of oxygen in the atmosphere,
>> enough for more than 1,000 years.  So hopefully we can get our heads aro
>>
>>
>
> --
> _______________
> Ken Caldeira
>
> Carnegie Institution for Science
> Dept of Global Ecology
> 260 Panama Street, Stanford, CA 94305 USA
> +1 650 704 7212 [email protected]
> http://dge.stanford.edu/labs/caldeiralab  @kencaldeira
>
> *Caldeira Lab is hiring postdoctoral researchers.*
> *http://dge.stanford.edu/labs/caldeiralab/Caldeira_employment.html*
>
> Check out the profile of me on NPR's All Things 
> Considered<http://www.npr.org/2013/04/22/176344300/this-scientist-aims-high-to-save-the-worlds-coral-reefs>
>
>

-- 
You received this message because you are subscribed to the Google Groups 
"geoengineering" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to [email protected].
To post to this group, send email to [email protected].
Visit this group at http://groups.google.com/group/geoengineering?hl=en.
For more options, visit https://groups.google.com/groups/opt_out.


Reply via email to