Climate change poses urgent socio-environmental challenges. Researchers argue that as target temperatures are not likely to be achieved, climate interventions such as solar geoengineering and carbon dioxide removal to limit temperature rises should be explored as additions to conventional mitigation and adaptation actions.

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.