This grant provides funds to support a workshop on the potential impacts of geoengineering on aquatic and terrestrial ecosystems. Geoengineering refers to techniques proposed to counteract the global warming produced by anthropogenic emissions of greenhouse gases. For example, a commonly discussed "solar radiation management" technique involves the injection of reflective aerosols into the stratosphere to cool the earth. Many proposed geoengineering schemes may have important and unexplored consequences to the ecosystems that populate our planet. These consequences result from intentional and unintentional changes to regional climates in ways that affect sensitive species. However, the geoengineering-research and ecosystem-research communities have only minor overlaps, and it would benefit each community, as well as society at large, to strengthen research interactions by involving ecosystem experts in predicting the potential hazards of geoengineering schemes. This workshop brings the two communities together to address four objectives: (1) to build connections between the ecosystem research and geoengineering-research communities, (2) to evaluate scientific uncertainties that affect the potential impacts of geoengineering on ecosystems, (3) to expose ecosystem researchers to current geoengineering research, and (4) to generate feedback for geoengineering researchers on potential ecosystem hazards of geoengineering. The first day of the workshop will be devoted to public lectures, and the remaining two days will be used to write a synthesis report on the topic of ecosystem impacts of geoengineering. The synthesis report will be presented to the International Geosphere-Biosphere Programme (IGBP), which is providing partial support for the workshop.
The scientific intellectual merit and broader impacts of the workshop are closely connected. Scientifically, geoengineering poses a challenge to our understanding of the climate system and the global ecosystem. On a practical level,geoengineering has been proposed as a response to the threat posed by global warming, and a better understanding of the consequences of geoengineering would be a valuable input to decision makers considering the implementation of geoengineering schemes.
Geoengineering, techniques to counteract global warming by modifying the Earth system rather than removing the primary causative agents – the greenhouse gases, has been suggested as a means to counteract dangerous climate change. Many proposed geoengineering schemes may involve important and unexplored consequences to the ecosystems that populate our planet. These consequences result from intentional and unintentional changes to regional climates in ways that affect sensitive populations. However, the geoengineering-research and ecosystem-research communities only have minor overlaps, and it would benefit each community, as well as society at large, to strengthen research interactions by involving ecosystem experts in predicting the potential hazards of geoengineering schemes. This issue has important societal relevance, since there is widespread discussion of geoengineering schemes for climate but very little substantive investigation of the potential hazards of these schemes or their unintended consequences. Potential changes to ecosystems are a key uncertainty that requires the participation of biologists with expertise in ecosystems in simulating the potential impacts of geoengineering proposed by geophysicists. Since geoengineering is inherently a global issue, this effort is organized with and cofunded by the International Geosphere-Biosphere Programme (IGBP), thereby broadening international collaboration. Our activity was bringing together ecosystem researchers and geoengineering researchers for a special workshop on Ecosystem Impacts of Geoengineering. The objectives of this workshop were (1) to build connections between the ecosystem-research and geoengineering-research communities, (2) to evaluate scientific uncertainties that affect the potential impacts of geoengineering on ecosystems, (3) to expose ecosystem researchers to current geoengineering research, and (4) to generate feedback for geoengineering researchers on potential ecosystem hazards of geoengineering. The experts who presented at the meeting were invited from four continents and more than a dozen countries, and their travel was co-sponsored by additional funds from IGBP provided by UK NERC. NSF funds were used to support meeting costs as well as travel for US experts. In addition, we supported the participation of three graduate student note-takers from U.S. graduate schools, whose participation allowed them to broaden their graduate education. Our findings from this workshop were summarized in a report that has been peer-reviewed and published in AMBIO. The contents of this report are summarized as follows: Geoengineering methods are intended to reduce climate change, which is already having demonstrable effects on ecosystem structure and functioning in some regions. Two types of geoengineering activities that have been proposed are: carbon dioxide (CO2) removal (CDR), which removes CO2 from the atmosphere, and solar radiation management (SRM, or sunlight reflection methods), which reflects a small percentage of sunlight back into space to offset warming from greenhouse gases. Current research suggests that SRM or CDR might diminish the impacts of climate change on ecosystems by reducing changes in temperature and precipitation. However, sudden cessation of SRM would exacerbate the climate effects on ecosystems, and some CDR might interfere with oceanic and terrestrial ecosystem processes. The many risks and uncertainties associated with these new kinds of purposeful perturbations to the Earth system are not well understood and require cautious and comprehensive research.
