Scientists have been sounding the alarm for months The rapid development of El Niñocould be reach record-breaking power when it peaks later this year. This is a concern because El Nino has dangerous and incredibly costly global consequences. exacerbates extreme weather conditions for disrupts the stability of food systems.
El Niño is a natural and vital phase of the El Niño-Southern Number (ENSO), which plays a major role in shaping climate variability from year to year. However, there are studies is displayed The long-term effects of a single El Niño event can cost the global economy trillions of dollars. As human-driven climate change exacerbates their effects and potentially increases the likelihood of stronger El Niños, some researchers are considering ways to mitigate them.
A study has been published Targeted use of a geoengineering technique called marine cloud brightening could weaken the nascent El Niño, the journal Science Advances reports today. In a computer modeling experiment, “we were able to turn what was an extreme or super El Niño into a neutral event, so at that point it was no longer an El Niño,” said Jessica Wan, a postdoctoral researcher at the University of Chicago who led the study during graduate school at the Scripps Institution of Oceanography.
Are you drowning in Super El Nino?
Marine cloud brightening injects aerosols into the lower atmosphere over the ocean, creating brighter marine clouds that reflect more sunlight into space. British cloud physicist John Latham first he suggested introduced the idea in 1990 as a means of slowing global warming, and since then numerous theoretical studies and some small-scale field trials have been conducted to confirm its effects.
The end goal in Wan’s research was different. Instead of trying to cool the entire planet, he and his colleagues wanted to see if a targeted marine cloud over the southeastern tropical Pacific could weaken the developing El Niño.
Researchers have never tried to change the strength of El Niño using marine cloud brightening, but the devastating bushfires in Australia in 2019 and 2020 acted as a natural experiment. Previous studies there is is displayed smoke from wildfires drifted over the sea and lit up a broad low-lying cloud layer hanging over the southeastern subtropical Pacific Ocean, contributing to an unusually long La Nina event that lasted from 2020 to 2023.
Using a previously established, widely used climate model, Wan and his colleagues first confirmed that smog particles are the main cause of the La Nina event. Confirming this, they then modeled the effects of man-made marine cloud brightening during the 1997-1998 and 2015-2016 El Niño events, which changed the magnitude and timing of the intrusion into the southeast Pacific.
These were both El Niños historically stronghowever, the results show that the brightening of marine clouds would have weakened them significantly. Under the most aggressive scenario, in which marine cloud brightening was applied from June to February, these super El Niños returned to an ENSO-neutral state.
“I would say we were very surprised,” Wan said.
Big questions remain unanswered
While the results are promising, there are important questions that need to be answered before researchers can begin real-world experiments. “This was obviously a really exciting finding, but we can really consider it more of a proof of concept than a ‘go-to’ approval,” co-author Katharine Ricke, an associate professor at Scripps, told Gizmodo.
The findings point to several big questions that need to be answered before researchers can even consider field experiments. One issue that requires further investigation is whether the weakening of El Niño by the brightening of the marine cloud hastened the onset of the subsequent La Niña.
“The implications of bringing in an earlier La Nina or more La Nina or potentially a bigger La Nina is something we want to look closely at,” Ricke said. Deliberate weakening of El Niño can also have additional unintended consequences, potentially triggering other modes of climate change or, if used repeatedly during multiple events, altering the exchange of heat and carbon between the atmosphere and ocean over time.
Clearly, there is much work to be done. But as another super El Nino takes shape, the study offers a glimpse into a future where scientists might be able to prevent its worst effects.
