Marine cloud brightening study shows potential to weaken El Niño

Scientists published a modeling study in *Science Advances* demonstrating that targeted marine cloud brightening—spraying tiny sea‑salt aerosol particles into clouds over the southeast Pacific—can reduce the intensity of strong El Niño events. Simulations of the 1997‑1998 and 2015‑2016 super El Niños showed the technique could shift a developing El Niño toward a neutral ENSO state, cutting associated heat, rainfall and economic damage. Early deployment was found to be most effective, and the study cited the 2019‑2020 Australian bushfire smoke as a natural analogue of cloud brightening. Researchers noted possible side‑effects, such as an earlier onset of La Niña, and called for careful assessment before any field tests.

The Panama Canal Authority, anticipating a 30 % drop in May precipitation linked to the emerging El Niño, announced a reduction in the maximum draft allowed for Neopanamax vessels—the first such limitation in two years—to preserve water for lock operations.

The findings add to ongoing debate over solar geo‑engineering as a climate‑risk mitigation tool, highlighting both its promise for tempering extreme weather and the uncertainties surrounding large‑scale atmospheric interventions.