Exploring Climate Cooling

• Rising global temperatures increase the likelihood of crossing climate tipping points – abrupt and potentially irreversible shifts in the Earth’s climate system. While decarbonisation is the only sustainable way to reduce the risk of triggering these events in the long term, our current warming trajectory already makes a number of tipping points distinctly possible over the next century. 

• This has driven international interest into approaches to actively reduce global temperatures in the short term.

• There is a crucial need for objective and trustworthy science in this area to better understand these proposed approaches. Our programme intends to answer fundamental scientific questions on the feasibility and risks of cooling approaches.

Yes. In cases where essential scientific questions cannot be answered by modelling or indoor experiments alone, five projects will undertake carefully controlled outdoor experiments to responsibly gather crucial real-world data. 

Any outdoor experiment will only go ahead once independent environmental impact and legal assessments have been made, and if the results of these suggest that the experiments will be safe (the assessments will also be made publicly available before experiments start). These experiments will only go ahead after a period of meaningful public engagement with local communities, and will all be subject to oversight by the programme’s independent oversight committee.

Our programme funds five outdoor experiments:

• One project will explore the efficacy of rethickening arctic sea ice.

• Two projects will explore the effects of seawater spray on cloud reflectivity.

• One project will explore the effects of electric charge on cloud reflectivity.

• One project studies how milligram quantities of mineral dusts age in the stratosphere. In this controlled experiment, none of these materials will be released; all are returned to the ground for analysis by scientists.

Crucially, all ARIA-funded experiments will be time-bound, limited in size and scale, and their effects will dissipate within 24 hours or be fully reversible. Experiments can only proceed if they fully meet ARIA’s stringent governance requirements. ARIA is not deploying these technologies, and there is no risk of termination shock.

We’re also funding 4 projects that will monitor natural climate processes:

• Two projects will examine different aspects of the formation and properties of cirrus clouds, to better understand how these clouds influence the climate.

• One project will develop a lightweight and low-cost balloon system for collecting climate data from the high atmosphere.

• One project will use drones to study emissions from selected, regularly erupting volcanoes to better understand the effects that the emissions from these volcanoes have on the climate. 

Remaining projects will research computer modelling, public perception, ecological studies, governance, and ethics in the field of climate cooling.

• Any outdoor experiments will first be subject to an independent and publicly available environmental impact and legal assessment, as well as a co-design process with local communities. 

• The first outdoor experiments are expected to commence in early 2026, and will be a continuation of ice thickening experiments being conducted in Canada. The teams conducting this ice thickening have worked in these communities before and will comply with local regulations.

• Outdoor experiments in the UK will only take place if the appropriate community engagement work and the necessary assessments have taken place. No decisions have been taken yet on the locations for UK-based experiments.