Addressing the urgent need for direct climate cooling: Rationale and options

Abstract

Emissions reduction and removal are not proceeding at a pace that will limit global average warming to less than the Paris Agreement targets of 1.5 °C or 2.0 °C. Accelerating global warming is indicated by record high 2023-24 monthly temperatures and annual 2023 global mean surface temperatures around 1.5 °C above pre-industrial levels. Only direct climate cooling has the potential to avert continued temperature rise in the near term and moderate at least some projected climate change disruption including extreme weather, sea level rise, loss of sea ice, glacier and permafrost melting, and coral reef die-off. Strategically deployed at scale, starting in the near term, several cooling measures have the potential to reduce or reverse global warming. Others can exert local or regional cooling influences. The world needs an approach to climate change that extends beyond sole reliance on emission reductions and removal. We propose a) researching, field testing and deploying one or more large-scale cooling influence(s) perhaps initially in polar regions and applying local and regional cooling measures that also support adaptation, b) accelerating emissions reductions with an early prioritization of short-lived climate drivers, and c) deploying large scale carbon removal to draw down legacy greenhouse gas. The authors make no attempt to determine what measures or mix of measures is optimal. That will depend on modeling and experimentation. Only by including properly researched emergency cooling “tourniquets,” in the near-term to our “bleeding” Earth can we slow and then reverse ongoing and increasingly severe climate change in the 21st Century.