The northern hemisphere’s “season of danger” got off to a chaotic start, those few months of the year that are accompanied by a parade of disasters. This year’s dangerous season already includes abnormally high sea surface temperatures in the world’s oceans, catastrophic forest fires in CanadaAnd unusual flooding in California.
Experts say the recent extremes are influenced by a hodgepodge of separate factors. Climate change is involved, but natural variations in global weather and an unfortunate dose of serendipity are also at play.
“Global warming itself has not suddenly accelerated this year,” Daniel Swain, a climatologist at the University of California, Los Angeles, said Monday during a live briefing. “Some of what happens is random bad luck.”
Last week, the U.S. National Atmospheric and Oceanic Administration announcement that El Niño conditions – above average sea surface temperatures that cause higher than usual heat in many parts of the world – were officially present in the Pacific Ocean. The shift from La Niña, the opposite extreme of El Niño, to an El Niño means a much warmer year is in store for the whole world. But the cycle, which is associated with extremes such as drought and severe storms, also has localized impacts. In eastern and southern Africa, the Horn of Africa, Latin America, the Caribbean, and parts of the Asia-Pacific region, El Niño can trigger famine, infectious disease outbreaks, and heat stress. The natural weather phenomenon can also have an impact, Swain said, on record temperatures at the earth’s surface in Canada which have helped fuel its devastating fire season so far.
At the same time, scientists have been keeping tabs on a separate phenomenon taking place in the Atlantic Ocean. Temperatures in the Atlantic hurricane region have been abnormally high for three months now. They are currently 82 degrees Fahrenheit on average – 35% higher than a previous recording set in 2005.
“There has never been a day in observed history when the entire North Atlantic was as warm as it is now,” Swain said. The rest of the Atlantic basin – the Gulf of Mexico and the east coast – is also warmer than average, meaning an active Atlantic hurricane season could be imminent. Generally, El Nino suppresses hurricane activity in the Atlantic and leading to a more severe typhoon season in the Pacific, but above-average temperatures in the Atlantic Ocean could negate the moderating effects of El Niño and fuel large hurricanes in the Atlantic this year.
A third factor, a volcanic eruption that occurred in early 2022 in the southern Pacific Ocean, is also contributing to above-average global temperatures. Volcanic eruptions usually have a temporary cooling effect on the planet as they shoot soot and other sun-blocking particles into the air. But the Hunga Tonga–Hunga Haʻapai eruption in the Tonga archipelago was not a typical volcanic eruption. “It was a huge, massively explosive sub-ocean eruption that basically vaporized huge amounts of seawater,” Swain said. The plume from the volcano was so intense that it ejected vaporized water into the stratosphere, where the vapor had a warming up effect on the planet.
All of this means that we are in a period of accelerated warming due to the convergence of these factors. The good news is that the warming effect that El Niño and the Hunga Tonga eruption are having on the planet is temporary. El Niño lasts between 9 and 12 months and the water vaporized in the stratosphere will fade within a few years.
More Grist coverage of El Niño from this year
The bad news is that climate change, which experts say contributed to the formation of El Niño this year and could be behind record ocean temperatures in the North Atlantic, continues to sway back. -plan. It’s not going away anytime soon.
“The long-term trend isn’t going to stop,” Swain said. “We are climbing steps on our way to much warmer oceans and a much warmer climate.”
