At a recent geoengineering conference two Harvard engineers announced plans for a real-world climate engineering experiment beginning in 2018.
The science of geoengineering has increasingly become a part of the public conversation around climate change and an ever-controversial topic within the scientific community. Geoengineering is a type of weather modification (or climate engineering) which has been researched, but, until recently, has been considered too unpredictable to attempt on a large scale. According to a 2013 congressional report:
The term ‘geoengineering’ describes this array of technologies that aim, through large-scale and deliberate modifications of the Earth’s energy balance, to reduce temperatures and counteract anthropogenic climate change. Most of these technologies are at the conceptual and research stages, and their effectiveness at reducing global temperatures has yet to be proven. Moreover, very few studies have been published that document the cost, environmental effects, socio-political impacts, and legal implications of geoengineering. If geoengineering technologies were to be deployed, they are expected to have the potential to cause significant transboundary effects.
In general, geoengineering technologies are categorized as either a carbon dioxide removal (CDR) method or a solar radiation management (SRM) (or albedo-modification) method. CDR methods address the warming effects of greenhouse gases by removing carbon dioxide (CO2) from the atmosphere. CDR methods include ocean fertilization, and carbon capture and sequestration. SRM methods address climate change by increasing the reflectivity of the Earth’s atmosphere or surface. Aerosol injection and space-based reflectors are examples of SRM methods. SRM methods do not remove greenhouse gases from the atmosphere, but can be deployed faster with relatively immediate global cooling results compared to CDR methods.
The U.S. government’s caution with geoengineering programs seems to be shifting as indicated by a new announcement related to an upcoming real-world climate engineering experiment. At the recent “Forum on Solar Geoengineering Research,” Harvard engineer (and consistent proponent of climate engineering) David Keith announced his plan for a new project that will assess the risks and benefits of deploying geoengineering on a large public scale. Keith and fellow engineer, Frank Keutsch, will research the benefits and risks by spraying particles such as sulfur dioxide, alumina, or calcium carbonate from a high-altitude balloon over Arizona during 2018.
The move to real-world testing of geoengineering should not come as a surprise given that in the final days of former-President Obama’s administration the U.S. Global Change Research Program released a report detailing the path of research into climate change, including new research on geoengineering. With the release of their report the GCRP became the first scientists in the federal government to formally recommend studies involving geoengineering. “The move will likely further normalize discussion of deliberate tinkering with the atmosphere to cool the planet, and of directly collecting carbon from the sky, both topics once verboten in the climate science community,” Science Mag predicted at the time.
David Keith said there will be a multi-phase plan for research and conducting real-world testing within the next 18 months. Keith also called for stratospheric spraying within three years and continuous spraying for at least a century. Technology Review reports that Keith said his team is already in the process of “engineering design work with Arizona test balloon company World View Enterprises,” and discussing the “appropriate governance structure for such an experiment.”