Targeted marine cloud brightening can dampen El Niño

[Geoengineering News]

https://arxiv.org/abs/2406.07853

Authors 

Jessica S. Wan, John T. Fasullo, Nan Rosenbloom, Chih-Chieh Jack Chen, Katharine Ricke

12 June 2024

Abstract

Many record-breaking climate extremes arise from both greenhouse gas-induced warming and natural climate variability. Marine cloud brightening, a solar geoengineering strategy originally proposed to reduce long-term warming, could potentially mitigate extreme events by instead targeting seasonal phenomena, such as El Niño-Southern Oscillation (ENSO). By exploiting the 2019-2020 Australian wildfire experiment-of-opportunity, we show that simulated marine cloud brightening in the southeast Pacific reproduces observed cloud changes and induces La Niña-like responses. We then explore how cloud brightening timing and duration modifies the 1997-1998 and 2015-2016 El Niño events. We find the earliest and longest interventions effectively restore neutral ENSO conditions and dampen El Niño's impacts. Solar geoengineering that targets climate variability could complement tools such as ENSO forecasting and provide a pathway for climate risk mitigation.

Source: ArXiv