The HOME! Alliance celebrates the defeat of a high-profile solar geoengineering experiment

March 21, 2024 – Just three weeks after Global South countries successfully blocked a dangerous push to legitimize solar geoengineering [1] at the 6th UN Environment Assembly (UNEA6) in Nairobi, Harvard University has announced the cancellation of the Stratospheric Controlled Perturbation Experiment, also known as SCoPEx, following years of international pressure.

The project was met with strong criticism and powerful opposition since it was first introduced, in particular from Indigenous Peoples Organizations and civil society groups, including the Hands Off Mother Earth! (HOME!) Alliance. In 2021, the Swedish Space Corporation called off a SCoPEx test flight in Kiruna, Sweden, following a campaign led by the Saami Council, and in the same year, international Indigenous Groups sent a petition to Harvard calling for the project to be shut down.

SCoPEx sought to test a controversial geoengineering technique called Stratospheric Aerosol Injection (SAI), which aims to partially block sunlight from entering the Earth’s atmosphere by releasing pollutants high in the atmosphere. SCoPEx’s open-air experiment involved using a high-altitude balloon that would release materials into the stratosphere and then measure the impact on the atmosphere’s chemistry and how sunlight passes through it.

When SCoPEx was announced in 2015 and later launched in 2017 it was the first proposed outdoor experiment to test SAI deployment technology, and would have crossed a line that many find unacceptable. SAI and other geoengineering technologies do nothing to address the root causes of climate change. They do however introduce new and profound risks including to the climate system, ecosystems and human rights.

“Projects like SCoPEx that intend to use our home planet as if it were a laboratory must be stopped altogether. The ultimate goal of these experiments is to legitimize solar geoengineering and pave the way for the deployment of this dangerous technology on a large-scale. This would provide big polluters with an excuse to continue the status quo while distracting from efforts to address the root causes of climate change.” Silvia Ribeiro, ETC Group.

“Our network celebrates the current decision to close down the SCoPEx project. The impacts of solar geoengineering would be disastrous for the climate, environment, humanity and all life as we know it, particularly when deployed at scale. We understand solar geoengineering to be a violation of Indigenous cosmovision, as well as the creative principles of the harmony of the natural ecological systems of Mother Earth and Father Sky. Indigenous Peoples are generationally educated to treat nature with love and respect, not as an experiment of a growing unethical techno-utopianism.” Tom BK Goldtooth, Executive Director, Indigenous Environmental Network (IEN)

“The cancellation of SCoPEx and the recent withdrawal of a Solar Radiation Modification resolution during the 6th United Nations Environment Assembly are two important victories for all who have been fighting for climate justice. They are an example of the power that Indigenous Peoples and civil society voices can have in shaping a sustainable and just future.” Sara Shaw, Friends of the Earth International (FOEI)

“Experiments like SCoPEx risk leading to development of technologies like SAI that should never be used. Solar geoengineering would mean fighting planetary-scale intergenerational pollution with planetary-scale intergenerational pollution and has no place in responding to the climate crisis. Extensive research and assessment to date shows that the only reasonable response for governments is to commit to Non-Use of SAI and other forms of Solar Geoengineering.” Mary Church, Center for International Environmental Law (CIEL)

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[1] Solar geoengineering carries inherent and unpredictable risks. By its very nature it is impossible to test without deployment, and there is no precedent in human history to give confidence that such a technology could ever be governed safely. It risks diverting attention away from real solutions to the climate crisis and, furthermore, the use of SAI could result in a “termination shock”, where global temperatures spiral out of control if deployment were to be suddenly ceased.

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