back to SpaCE Lab Research Overview
Climate Intervention Biology
Climate change and associated global warming is caused by humans (IPCC 2013). The solution is to stop greenhouse gas emissions by eliminating dependence on fossil fuels (IPCC 2013, 2014). Climate intervention, or "geoengineering" is a set of proposed activities deliberately designed to counter the impacts of environmental change resulting from global warming. It has received increasing attention in the face of failure to limit the inputs of greenhouse gases to the atmosphere (NASEM 2021).
Many schemes for climate intervention have been proposed. There are two main groups of activities aimed at reducing the amount of carbon dioxide in the atmosphere: activities that focus on Carbon Dioxide Removal, CDR, including nature-based solutions like reforestation and afforestation, as well as direct CO2 capture; and activities aimed at partially reducing the amount of incoming solar radiation at the surface by increasing the albedo (reflectivity) of the Earth-atmosphere system in order to temporarily cool the planet (e.g., through Solar Radiation Modification, SRM, which includes Stratospheric Aerosol Intervention (SAI) and Marine Cloud Brightening (MCB)). In particular, SAI has received considerable study by climate scientists as a temporary strategy that may help forestall the worst impacts of anthropogenic climate change as emissions reductions occur. However, climate intervention alone will not remove all the impacts of anthropogenic climate change and should not be considered the solution. Emissions must stop for Earth’s temperature to stay within 1.5°C above pre-industrial levels (IPCC 2018).
Whereas climate science research on this topic has been ongoing for decades, there is a dearth of information on the potential impacts of climate intervention on ecological systems including risks to biodiversity and ecosystem functions and services.
In addition to researching this topic, Phoebe served on a National Academy of Sciences, Engineering, and Medicine (NASEM) committee, Climate Intervention in an Earth Systems Science Framework: A Workshop.
By conducting research on the topic of climate intervention, we are filling important knowledge gaps; we do not endorse or advocate either testing or actual implementation of climate intervention.
Many schemes for climate intervention have been proposed. There are two main groups of activities aimed at reducing the amount of carbon dioxide in the atmosphere: activities that focus on Carbon Dioxide Removal, CDR, including nature-based solutions like reforestation and afforestation, as well as direct CO2 capture; and activities aimed at partially reducing the amount of incoming solar radiation at the surface by increasing the albedo (reflectivity) of the Earth-atmosphere system in order to temporarily cool the planet (e.g., through Solar Radiation Modification, SRM, which includes Stratospheric Aerosol Intervention (SAI) and Marine Cloud Brightening (MCB)). In particular, SAI has received considerable study by climate scientists as a temporary strategy that may help forestall the worst impacts of anthropogenic climate change as emissions reductions occur. However, climate intervention alone will not remove all the impacts of anthropogenic climate change and should not be considered the solution. Emissions must stop for Earth’s temperature to stay within 1.5°C above pre-industrial levels (IPCC 2018).
Whereas climate science research on this topic has been ongoing for decades, there is a dearth of information on the potential impacts of climate intervention on ecological systems including risks to biodiversity and ecosystem functions and services.
In addition to researching this topic, Phoebe served on a National Academy of Sciences, Engineering, and Medicine (NASEM) committee, Climate Intervention in an Earth Systems Science Framework: A Workshop.
By conducting research on the topic of climate intervention, we are filling important knowledge gaps; we do not endorse or advocate either testing or actual implementation of climate intervention.
Project 1: NSF-funded Climate Intervention Biology Working Group
|
This NSF-funded research focuses on understanding and predicting potential impacts of climate intervention on ecological systems, from species to biomes. The Climate Intervention Biology Working Group consists of climate scientists and ecologists, co-led by Phoebe Zarnetske and Jessica Gurevitch. See the working group's website which outlines the working group activities focused on studying the potential ecological impacts and risks of SAI and other solar geoengineering schemes: https://www.climateinterventionbiology.org/.
|
The effects of solar radiation modification (SRM) with stratospheric aerosol intervention (SAI) on ecological systems are largely unknown. Image Credit: Phoebe Zarnetske; symbols courtesy of the Integration and Application Network, University of Maryland Center for Environmental Science (ian.umces.edu/symbols/). This image is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND). See also Figure 1 in Zarnetske et al. 2021 PNAS: 10.1073/pnas.1921854118.
Change in projected surface temperature in 2080-2100 without mitigation (left) compared with a stratospheric aerosol injection scenario (SAI) (right). Although SAI may cool the planet down to a certain temperature target, there are potentially large impacts on ecosystems (right). Credit: Dan Visioni.
|
Project 2: Climate Change, Climate Intervention, & Extreme Events (Marine Heat Waves)
Marine heat waves (MHW) have major ecological impacts in marine ecosystems including biodiversity loss, changes in species behavior or performance, loss of genetic diversity and adaptive capacity, economic impacts from changes in fishery catch rates and mortality of species. Although climate intervention aims to reduce global mean temperature, some climate intervention scenarios may moderate extreme climatic changes such as heat waves. Yet quantifying the potential impact of climate intervention on marine heat waves (MHW) has not been addressed. The aim of this study is to estimate projected future MHWs and their responses under (1) climate change (SSP2-4.5 scenario), and (2) under solar climate intervention with stratospheric aerosol intervention (SAI; ARISE-SAI 1.0 and ARISE-SAI 1.5 scenarios)). We quantified MHW frequency, duration, and intensity for futures with and without SAI during 2035-2069 from the earth system model: Community Earth System Model, version 2 (CESM2).
Our results in Kounta et al. 2026 Environmental Research: Climate show that, despite SAI reducing the global average maximum intensity and duration of MHWs relative to SSP2-4.5, the magnitude of these effects varies spatially. Compared with the present climate, SAI scenarios would reduce MHW intensity in 25-76% of the ocean and duration in 21-80% of the ocean. The largest future reductions in maximum intensity and duration occur in coastal regions and in the Tropical Atlantic, Indian, Arctic, and South Atlantic oceans. Even with a more aggressive mitigation scenario (ARISE-SAI-1.0), nearly 25% of the ocean would remain unaffected, with areas such as the North Atlantic, Tropical Pacific, and parts of the Southern Oceans still experiencing more intense and longer MHWs, posing risks to marine life.
Our results in Kounta et al. 2026 Environmental Research: Climate show that, despite SAI reducing the global average maximum intensity and duration of MHWs relative to SSP2-4.5, the magnitude of these effects varies spatially. Compared with the present climate, SAI scenarios would reduce MHW intensity in 25-76% of the ocean and duration in 21-80% of the ocean. The largest future reductions in maximum intensity and duration occur in coastal regions and in the Tropical Atlantic, Indian, Arctic, and South Atlantic oceans. Even with a more aggressive mitigation scenario (ARISE-SAI-1.0), nearly 25% of the ocean would remain unaffected, with areas such as the North Atlantic, Tropical Pacific, and parts of the Southern Oceans still experiencing more intense and longer MHWs, posing risks to marine life.
- Lab Members: Phoebe Zarnetske, Lala Kounta
- Collaborators: Lifeng Luo, Gouri Anil, Daniel Hueholt, Cheryl S Harrison, Daniele Visioni, Mari Tye, Tyler Felgenhauer, Amadou T Gaye
- Funding: MSU Alliance for African Partnerships African Future Leadership Program (2022-2023), 1-yr MSU EEB Seed Grant (2024).
- Publications:
- Kounta et al. 2026. Environmental Research: Climate. DOI: 10.1088/2752-5295/ae7b74.
- Press:
- Could a controversial cooling strategy save our fisheries and coral reefs from marine heat waves? Cooling strategy not a panacea for marine heat waves. MSU EEB Press Release & MSU Today
- re-posted by: United Nations Office of Disaster Risk Reduction's Prevention Web, EurekAlert, MSN
- Solar geoengineering could shield up to 75% of oceans from heat waves. Phys.org
- A controversial plan to cool Earth may leave part of the ocean exposed. Earth.com
- Could a controversial cooling strategy save our fisheries and coral reefs from marine heat waves? Cooling strategy not a panacea for marine heat waves. MSU EEB Press Release & MSU Today
- Project Website: https://www.climateinterventionbiology.org/
- GitHub: https://github.com/srm-ecology
MHW frequency across future scenarios for 2050–2069. Results are from the Earth System Model CESM2 and are the annual mean of ten ensemble members. Panels represent A) a scenario without climate intervention (business as usual; SSP2-4.5), B) a future SAI scenario with a temperature target of 1.5 degrees C above pre-industrial level (ARISE-SAI-1.5), and C) a future SAI scenario with a temperature target of 1.0 degree C above pre-industrial level. Adapted from Kounta et al. 2026 Environmental Research: Climate.
Project 3: In the context of extreme events and biotic interactions, how will SAI alter ecological structure and function?
Extreme events can have large impacts on organisms to ecosystems. We are combining big data approaches with climate analog analysis and aquatic mesocosm experiments to understand and predict how extreme events in the future (with and without SAI) will impact the structure and function of ecological systems. Specific outcomes of this project include: (1) quantifying global extreme events across multiple SAI and non-SAI scenarios for a variety of abiotic variables important to ecology, (2) applying space-for-time analog analysis using these future scenarios, biodiversity range maps, and trait distributions to identify existing SAI analogous abiotic conditions and associated ecological communities, and (3) experimentally testing the effects of SAI vs. no-SAI futures on biotic interactions within a multi-trophic aquatic food web. The findings will advance our understanding of the influence of potential SAI deployment on global ecosystems.
A main contribution of this research is a data paper, "Global gridded data of extreme events under alternate futures with and without climate intervention with stratospheric aerosol injection," currently in preparation. It extends the scope beyond the published MHW paper's single-model ARISE-SAI ensembles (Kounta et al., 2026. Environmental Research: Climate) to a multi-model, multi-SAI experiment: ARISE-SAI-1.5/1.0 (CESM2-WACCM6), the GeoMIP G6-1.5K-SAI, and G6-1.5K-HiLLA experiments, as well as marine cloud brightening (MCB) simulations. The dataset translates these climate intervention model outputs into ecologically and socially relevant indicators, including the frequency, intensity, and duration of land and marine heatwaves, precipitation and temperature extremes, and light/ozone/UV bioclimatic indicators — all at common spatial resolutions to support integration with biodiversity, ecosystem, and socioeconomic data.
A main contribution of this research is a data paper, "Global gridded data of extreme events under alternate futures with and without climate intervention with stratospheric aerosol injection," currently in preparation. It extends the scope beyond the published MHW paper's single-model ARISE-SAI ensembles (Kounta et al., 2026. Environmental Research: Climate) to a multi-model, multi-SAI experiment: ARISE-SAI-1.5/1.0 (CESM2-WACCM6), the GeoMIP G6-1.5K-SAI, and G6-1.5K-HiLLA experiments, as well as marine cloud brightening (MCB) simulations. The dataset translates these climate intervention model outputs into ecologically and socially relevant indicators, including the frequency, intensity, and duration of land and marine heatwaves, precipitation and temperature extremes, and light/ozone/UV bioclimatic indicators — all at common spatial resolutions to support integration with biodiversity, ecosystem, and socioeconomic data.
- Lab Members: Phoebe Zarnetske, Lala Kounta, Kelly Kapsar, Ruoyu (Sophia) Chen
- Collaborators: MSU: Lifeng Luo, Alisha Shah, Kelly Kapsar, Elena Litchman, Cornell: Daniele Visioni, Cindy Wang; The Nature Conservancy: Nick Wolff, Ava Nafiseh Haghtalab; Saint Mary's College: John Grady; Reflective: Alistair Duffy, John Orcutt, Francis Osei Tutu Afrifa.
- Funding: Environmental Defense Fund (11/2025-02/2027).
- Press:
- GitHub: https://github.com/srm-ecology
