Climate change and El Niño fuel monster hurricane, scientists warn of Polo’s rapid rise

Warm waters powered Polo

The research linked Polo’s rapid strengthening to a combination of climate change and El Niño. Ocean temperatures reached 88 degrees Fahrenheit (31.2 degrees Celsius), as much as 3.6 degrees Fahrenheit (2 degrees Celsius) above normal, according to the study.

Researchers estimated that climate change made those conditions 23 times more likely, while El Niño made them 14 times more likely. They said Polo would still have been powerful without either influence, but additional wind speed can substantially increase the potential for damage.

Climate change’s larger influence

Study co-author Friederike Otto said both factors strengthened Polo, but climate change had the greater effect. Otto is a climate scientist who coordinates the international team behind World Weather Attribution.

Kristina Dahl, a Climate Central climate scientist, said El Niño shifts hazards around the world, while climate change remains the dominant influence. The study assessed warm-water conditions that can support tropical storms, but did not examine upper-level wind shear.

El Niño generally brings storm-weakening high-altitude winds to the Atlantic. In the Pacific, shifting wind patterns reduce those winds, according to the reporting.

Methods and scientific debate

The teams compared current climate observations with a modeled world without the 2.5 degrees (1.4 degrees Celsius) of warming since pre-industrial times. Daniel Gilford of Climate Central said he used a conservative approach while accounting for other conditions.

Brian Tang, an atmospheric scientist at the University at Albany who was not involved in the research, said he was surprised climate change was identified as the larger influence, given the strength of El Niño. He added that the finding may be less surprising over the long term.

Three outside scientists—Jeff Masters, Michael Mann and Carl Schreck—said the research may underestimate climate change’s contribution to Polo’s strength. Gilford acknowledged that the report could slightly underestimate the effect.