The Hutchison medal was recently awarded to a multinational group of academics* for their paper 'Ocean fertilization for geoengineering: a review of effectiveness, environmental impacts and emerging governance'. The medal is awarded annually by the Institution of Chemical Engineers (IChemE) for practical and wide-ranging, philosophical or thought-provoking published papers that will stimulate further debate within the chemical engineering community.
The paper provides a review the state of knowledge on large-scale ocean fertilization by adding iron or other nutrients, either from external sources or via enhanced ocean mixing. It arose directly from a scientific summary for policy makers by the same authors, published by the Intergovernmental Oceanographic Commission (IOC-UNESCO) with the assistance of the Surface Ocean-Lower Atmosphere Study (SOLAS).
Few subjects are as controversial as geoengineering –the deliberate intervention in the planetary environment of a nature and scale intended to counteract anthropogenic emissions. The potential side effects of geoengineering are presently not well understood and will likely include unintended ecological consequences, which in turn can pose important political, social, and ethical challenges. In truth, dangerous climate change is best avoided by drastically and rapidly reducing greenhouse gas emissions. Nevertheless, geoengineering options are receiving attention on the basis that additional approaches may also be necessary.
The paper highlights that, while ocean fertilization can increase the uptake of CO2 across the ocean surface, long-term sequestration is difficult to assess, and unintended impacts of ocean fertilization may be far removed in space in time. It further concludes that 'research results to date, taken together, do not support the idea that ocean fertilization would provide a particularly effective approach to counteract the increasing atmospheric levels of CO2, even within a wider portfolio of measures. The avoidance of undesirable climate change therefore requires more direct and urgent policy action.'
The United Nations General Assembly has encouraged States to support further study and to enhance understanding of ocean fertilization. Member States have stressed repeatedly that the precautionary principle is fundamental to the regulation of ocean fertilization, notably during the 25th IOC-UNESCO Assembly in 2009, the 2012 Conference of the Parties to the Convention on Biodiversity and in the outcome document of the United Nations Conference on Sustainable Development (Rio+20) adopted in 2012, which states ‘We stress our concern about the potential environmental impacts of ocean fertilization. In this regard, we recall the decisions related to ocean fertilization adopted by the relevant intergovernmental bodies, and resolve to continue addressing ocean fertilization with utmost caution, consistent with the precautionary approach’ (The Future We Want, §167).
* Authors: Phillip Williamson (UK), Chris Vivian (UK), Shigenobu Takeda (Japan), Ulf Riebesell (Germany), Yves Collos (France), Peter Croot (Ireland), Kenneth Denman (Canada), Cliff Law (New Zealand), Philip Boyd (Australia) and Douglas Wallace (Canada)