Scientists have proposed a way to mitigate El Niño
An international team of scientists has proposed an unusual way of mitigating El Niño — one of the most powerful climatic phenomena on Earth. According to computer modelling, this could be achieved by artificially brightening the clouds over the equatorial Pacific Ocean. However, the researchers stress that the technology is not yet ready for practical application and could cause undesirable climate changes in other regions of the world.
El Niño is caused by abnormal warming of the sea surface in the eastern Pacific Ocean. This phenomenon affects weather patterns around the world, causing droughts, floods, heatwaves and other extreme events.
The authors of the new study have proposed increasing the albedo of marine clouds. To achieve this, it is theoretically possible to spray minute particles of sea salt into the atmosphere, which make the clouds brighter and allow them to reflect more sunlight back into space.
Details
The idea arose following a study of the consequences of the large-scale bushfires in Australia in 2019–2020. At that time, smoke particles accidentally made the clouds lighter, which scientists believe contributed to the development of a multi-year La Niña – the opposite phase of the climate cycle.
The researchers modelled two strong El Niño events – those of 1997–1998 and 2015–2016.
According to the calculations, the best effect is achieved if cloud brightening begins in June and continues until February of the following year.
In this scenario, the model showed a significant reduction in temperature and weather anomalies. Many regions that become too hot or too wet during El Niño returned to more familiar climatic conditions.
Why the method cannot yet be used
Despite the promising results, this is purely a matter of computer modelling.
Implementing the project would require around 2,400 specialised vessels capable of continuously spraying sea salt over the ocean. No such technology currently exists.
Furthermore, the modelling has revealed potential side effects. For example, the intervention could lead to further warming in Europe and certain parts of Asia. Scientists also do not yet know what the consequences of repeated use of this method would be.
Why this is important
The study shows that local geoengineering could potentially be one way of mitigating the effects of climate change. However, the authors emphasise that such technologies cannot replace reductions in greenhouse gas emissions and require very thorough safety assessments.
Source
Science Advances (2026): Jessica S. Wan et al. Targeted marine cloud brightening weakens subsequent El Niño.