[extropy-chat] Global warming news

Hal Finney hal at finney.org
Sat Mar 25 22:15:41 UTC 2006

I found some good resources on the "ocean fertilization" idea: trying
to mitigate CO2 buildups by seeding the oceans with iron and possibly
other minerals.  This is an area of active and ongoing research with a
number of experiments in recent years, and supposedly more being planned.
The results have generally been successful although none of them have been
long-term or large enough to address the many questions which still exist.

This long Wired article from 2000 was the first I heard of the subject:
<http://www.wired.com/wired/archive/8.11/ecohacking_pr.html>.  It talks
about some of the experiments from the 90s, and a commercial company
(now at greenseaventure.com) which has been trying to get approval for
the technology.

A more recent site covering many of the issues is at
<http://www.bbm.me.uk/FeFert/index.htm>.  It describes the history of
the idea, shows a map of where trials have been done, and also has a
good discussion of the risks and potential problems.

Nature had an article in 2004 about one of the experiments.  The news
report is here,
<http://www.nature.com/news/2004/040419/full/040419-7.html>, but you
need a subscription to read it.

Most of the current work is aimed at using the Southern Ocean which
surrounds Antarctica as a site for potential CO2 mitigation.  This is a
large iron-poor area and is conveniently far from fishing and shipping
lanes, so there is room for the large fleet of barges that would be
needed for large scale mitigation work.  However the Nature article and
another I have found,
both say that fertilizing the Souther Ocean could only counter 15%
of the annual human addition of CO2 to the air.  This suggests that the
technique has limited potential unless it can be expanded to other oceans,
which will introduce new logistic problems.

Costs are estimated at $1-5 per ton of CO2 sequestered, which is
claimed to be 10 to 40 times less than costs of other mitigation and
even conservation measures.

The Wikipedia article, <http://en.wikipedia.org/wiki/Iron_fertilization>,
closes with a number of potential objections to the proposal, but
supporters are given the last word.  Apparently iron fertilization
of the seas does occur naturally to some extent due to dust storms,
so the basic process is not completely novel.  Nevertheless keeping it
up continually for decades could have unpredictable ecological effects.

At this point it is certainly an idea which is "in play" and which may
well turn out to be an important technology for CO2 mitigation a few
decades hence.  It does require a change of attitudes but as I noted,
the more bad news we hear about global warming the more people are going
to look seriously at global-scale mitigation technologies like this one.
The fact that it is so cheap compared to alternatives makes it impossible
to ignore, even though it represents everything environmentalists hate
about humanity and its relationship to nature.


More information about the extropy-chat mailing list