Area of investment and support

Modelling environmental responses to solar radiation management

This Natural Environment Research Council (NERC) research programme will carry out climate modelling to understand the impacts of solar radiation management (SRM) techniques if implemented at scale.

• Budget: £ 10.5 million
• Duration: A five-year programme running from 2025 to 2030, with a single call for research projects during the programme lifetime.
• Partners involved: Natural Environment Research Council (NERC)

The scope and what we're doing

This research will model how key aspects of Earth systems would respond to solar radiation management (SRM) approaches to control Earth surface temperature if implemented at scale.

The programme will deliver independent cutting-edge environmental science, through modelling and (potentially) laboratory work to improve that modelling. The programme doesn’t support outdoors research.

The research will deliver ‘risk-risk analyses’ which consider the detrimental impacts of Earth heating under climate scenarios versus the response where SRM is deployed.

Four research themes

There will be four research themes covering the breadth of potential SRM approaches. They will gather knowledge from adjacent areas and existing data, and build a more complete understanding for SRM.

The themes are:

• theme 1: better understanding of the climate impacts of stratospheric aerosol intervention (SAI)
• theme 2: better understanding of the climate effects of marine cloud brightening (MCB)
• theme 3: using natural analogues and mining of existing data to understand SRM
• theme 4: novel SRM techniques – understanding the climate impacts from (to date) lesser-studied SRM techniques

The programme will include a dedicated programme coordination function which will work with the research projects to:

• coordinate research efforts between teams and ensure sharing of knowledge
• engage with policymakers
• engage with international activity in SRM
• consider the implications for ethics and governance from the research of the programme

To inform the last activity, there will be a public dialogue associated with this research programme to bring in wider understanding of public perception, involving the programme coordination function and the research projects.

Why we're doing it

Current climate mitigation efforts are widely acknowledged to fall short of keeping global mean temperatures below 1.5 to 2°C above pre-industrial levels, which is the target that would limit societal and ecological impacts.

In response, more extreme intervention ideas have proliferated, including ‘climate intervention’ (sometime referred to as geoengineering). Of these many approaches, the largest uncertainty exists with solar radiation management (SRM) techniques which propose to cool the Earth by reflecting away sunlight (solar radiation).

Currently many uncertainties exist in SRM modelling, including structural and parametric uncertainties in representing detailed atmospheric processes, dynamics and feedbacks. These result in different distributions of climate forcing.

These variables are compounded by uncertainties in climate models, leading to significant challenges in predicting climate impacts. Therefore, there is a need to develop an understanding of Earth system responses to ensure there exists independent and trustworthy research in this field.

Simulations with the same climate models used by the Intergovernmental Panel on Climate Change (IPCC) show that SRM can reduce negative impacts of climate change. However, SRM may have its own detrimental side effects, and this research seeks to understand what these are.

This understanding must then be contextualised via risk-risk assessments: estimating detrimental impacts of Earth heating under climate scenarios versus the impact on Earth systems where SRM is deployed.

Future discussions of geoengineered climate intervention must be supported by robust scientific research, which is free from vested interests. NERC investment in strategic research in this area will provide impartial evidence for international comparisons to make informed decisions on SRM.

Who to contact

Ask a question about this area of investment

Email: srm@nerc.ukri.org

Last updated: 28 February 2024