First, I think would be instructive to review the events that occurred
between 1980 and 1991, as background information on what I consider
to be a controversial topic and to provide some hints of what may
be coming in the future.
A lot of what we're talking about at this symposium today started
in 1988, when the late John Martin developed the iron hypothesis.
This was a very significant event.
Some scientists already knew about Martin's hypothesis that iron
might limit primary production in certain parts of the world's ocean;
the scientific publication greatly increased this recognition, and
1989 was a very active year. There was a lot of discussion, excitement,
interest; and many scientific publications were being prepared in
those years. There was enough interest to generate a workshop that
was conducted in December 1989 by the Natural Research Council Board
on Biology. This workshop came up with some findings, one of which
was that it's conceptually feasible to slow the increase of atmospheric
CO2 levels through enhanced new primary production, and the estimate
was two gigatons carbon per year at a cost of less than $2 billion
per year. The recommendation went on to say that, after careful
modeling and appropriate preliminary experiments in regions with
unused nutrients, international transient iron-enrichment experiments
should be implemented, at an estimated cost of $50 million to $150
went on during the interval between December 1989 when the NRC study
was formed, and May 1990 when the report was published, was in some
ways similar to what's going on now. Controversial ideas of large-scale
fertilization experiments in the ocean to modify the climate were
being discussed very seriously and were also being challenged in
the scientific community.