Iron Fertilizations of Oceans to Stop Global Warming

[Luke_Wilbur]

Researchers from the Woods Hole Oceanographic Institution (WHOI) will host a public forum this week to discuss the pros and cons of "iron fertilization" of the oceans as a means to mediate global warming.

 

The forum, entitled "Ocean Fertilization: Ironing Out Uncertainties in Climate Engineering," is a public follow-up to an interdisciplinary science workshop conducted at WHOI in September.

 

The free event will be held at 2:30 p.m. on October 19 in the Redfield Auditorium on Water Street in the Village of Woods Hole.

 

The discussion of iron fertilization comes in response to several recent scientific and commercial proposals to spread dissolved iron into the sea. This "seeding" of the ocean is intended to promote the growth of carbon dioxide-consuming plants (phytoplankton) that could help offset rising concentrations of greenhouse gases in the atmosphere.

 

Many ocean scientists are skeptical about whether the process would remove carbon dioxide for the long term or just for a fleeting time. The ecological impact of long-term, large-scale fertilization is also a concern.

 

"Could adding iron to ocean waters stimulate algal productivity sufficiently to reduce atmospheric carbon dioxide and geo-engineer our climate? We still don't know," said Ken Buesseler, a WHOI marine chemist and organizer of both the scientific and public discussions. "We did not set out to reach a consensus for or against ocean iron fertilization as a climate mitigation strategy, nor did we endorse any particular commercial plan to try it. Our goal is to bring together the many stakeholders and come to some agreement on the issues of concern and the holes in our knowledge."

 

During the September workshop at WHOI, 80 researchers, environmental advocates, regulators, and business leaders discussed previous scientific iron fertilization experiments, the variability in environmental responses to those experiments, and the intended and unintended consequences that may result when such projects are conducted on a larger scale. Participants also considered the legal and economic framework for regulating the use of international waters and for verifying that carbon is actually removed from the atmosphere for more than a passing moment.

 

Participants generally agreed that any evaluation of iron dumping must include detailed estimates of the impacts of adding iron, beyond simple measurements of algal growth. That is, they must consider the likely production of other greenhouse gases, the changes to ecosystems, and the efficiency and permanency of carbon sequestration. Workshop attendees also agreed that more extensive scientific assessments are needed than what is currently planned in some commercial proposals.

 

"While there is still no agreement on the efficiency of CO2 reduction or its environmental impacts, some scientists are willing to consider further experiments to address these remaining uncertainties, given that future policies and carbon-offset markets may emerge with or without a sound scientific basis," Buesseler said.

 

The public forum next week will offer background on the issue, while providing insight into the opinions and prevailing views expressed at the September workshop. A short, formal talk by Buesseler will be followed by a panel discussion and a public question-and-answer session.

 

The event is sponsored by the WHOI Elisabeth and Henry Morss Jr. Colloquia Fund, established to support public colloquia on issues of global importance to the human race.