While traditional mitigation targets emission reduction and cleaner energy, concerns that future emissions will breach temperature targets motivate exploring more radical options like solar geoengineering and carbon dioxide removal. 

Authors of the article Solar geoengineering and carbon removal significantly lower economic climate damages published in journal One Earth argue that by supplementing mitigation activities with moderate solar geoengineering it is possible to achieve the global climate target of 1.5°C, with climate damages similar to the sustainable development pathway.

According to the researchers both methods, solar geoengineering and carbon removal, face political challenges. 

– Carbon dioxide removal is an aggressive and technologically challenging, hence costly method. Solar geoengineering, meaning approaches to cool the Earth by reflecting sunlight back into space, is considered socially controversial due to many uncertainties associated with its exploitation. Our task as researchers is to compare alternative futures so policymakers and stakeholders can more realistically evaluate responses to climate change including combinations of radical and diverse mitigation measures, says one of the authors, research professor John Moore. 

Cost-effective mitigation combines emissions cuts and moderate geoengineering 

Quantification of economic impacts of climate change is essential for political decision making and risk management. 
Climate change damages and social cost of carbon have been compared various greenhouse gas emission scenarios and have not addressed additional measures such as solar geoengineering.  

In the new study researchers evaluate the economic implications of various scenarios, including solar geoengineering and carbon dioxide removal.

– Our findings highlight the importance of considering these strategies alongside conventional mitigation and adaptation actions. Our research provides valuable insights for policymakers and risk managers in formulating effective and equitable climate change policies and strategies, Moore explains.

Existing Integrated Assessment Models face challenges in incorporating solar geoengineering scenarios due to their limited ability to accurately represent the complex and uncertain impacts of geoengineering on global climate patterns and regional climate dynamics.

– With the rapidly growing profile of geoengineering in the scientific and policy communities, it is increasingly pertinent to compare the economic impacts of geoengineering scenarios against other scenarios in terms of climate damages, Moore continues. 

– It is important to be clear that there is almost certainly no chance of achieving 1.5C targets by reducing greenhouse gas emissions. The only choices are very large carbon dioxide removal programs that are well beyond current capabilities, solar geoengineering interventions and accepting damages from stronger warmings.

More information:

John Moore, Research professor
Arctic Centre at the University of Lapland
tel: +358 400 194 850
email: john.moore.bnu(at)gmail.com, john.moore(at)ulapland.fi

Publication information:
Article online (open access): Solar geoengineering and carbon removal significantly lower economic climate damages publiseh October 11,2023.
Paper will also be published in the October 20th issue of One Earth.