Characterising the Global and Regional Impacts and Risks of Alternative Materials for Stratospheric Aerosol Injection

Despite the increasing climate risks associated with human-induced warming of the Earth’s surface, there are growing concerns about whether planned greenhouse gas (GHG) emission reductions will keep warming below 2 degrees Celsius. Various other approaches to reduce global warming — including altering the Earth’s radiation budget — have been suggested in parallel with efforts to further reduce GHG emissions. One approach, often referred to as solar radiation modification, involves the injection of reflective aerosols into the stratosphere to counterbalance human-induced warming by reflecting some incoming solar radiation back to space, reducing warming at the Earth’s surface. While several modelling studies have shown the great potential of stratospheric aerosol injections in cooling the Earth, its spatially heterogeneous impacts on precipitation could increase the risk to food security across the most climate-vulnerable regions across the globe. Additionally, sulphate aerosol precursors (e.g., sulphur dioxide) have been almost exclusively used in most studies despite their negative influence on the ozone layer and their ability to heat the stratosphere significantly. This project seeks to improve understanding of the potential impact of alternative materials (e.g., diamond, dust, calcite, etc.) on the climate and the environment relative to sulphate aerosols. It aims to characterize the global and regional climate response to these alternative materials using climate model simulations that incorporate more advanced stratospheric chemistry representations that are currently being developed at the National Centre for Atmospheric Research (NCAR). The project will also explore the implications of the simulated climate response for agriculture, biodiversity, energy and water resources across Africa. In collaboration with the NCAR, this project will contribute to building capacity in SAI modelling across Africa.

Romaric C. Odoulami earned his Ph.D. in climate science and meteorology (2016) from the Federal University of Technology, Akure (Nigeria). He is currently a research fellow for the African Climate and Development Initiative at the University of Cape Town, which he joined in 2017 as a postdoctoral research fellow. In 2023, Odoulami was ranked as a young researcher with the potential to establish himself and become a globally recognized leader in his research fields by the South African National Research Foundation. That same year, as part of the winning team led by Mark New, he was awarded the Frontiers Planet Prize, which honors research that contributes towards solutions to planetary environmental challenges such as climate change, biodiversity loss and water resources. Odoulami’s research focuses on climate change risks, adaptation and mitigation with a specific focus on Africa. His research includes improving and contributing to the understanding of (i) climate processes, climate projections and modelling, climate change risks and attribution, (ii) climate change impacts and its implications for agriculture, food systems, water resources, biodiversity and health, (iii) and the potential of geoengineering climate interventions and their implications for society. Odoulami currently serves in the interim Scientific Steering Group of the World Climate Research Programme (WCRP) Lighthouse Activity – Research on Climate Intervention. He has served as a contributing author to chapter nine of the IPCC Working Group II Sixth Assessment Report.