Washington– The natural El Niño cycle, which distorts weather around the world, is fueling and shaping global warming, meteorologists said.
A new study calculates that an unusual recent development in the warming and cooling cycle that includes El Nino and its counterpart La Nina could help explain the scientific mystery of why the Earth’s already high temperature has reached a new high over the past three years.
Separately, scientists have had to update how they classify El Niño and La Niña due to rapid climate changes caused by global warming. Increasingly hot waters globally caused a warning to the US National Oceanic and Atmospheric Administration this month To change how it is calculated When the weather pattern turns to a new cycle. This likely means that more events will be considered La Niña and fewer qualify as El Niño due to warming of tropical waters.
Average monthly temperature of the Earth He took a noticeable jump upward of the long-term upward trend associated with human-caused climate change in early 2023, and this increase continues until 2025. Scientists have several theories about what is happening, including Acceleration of global warmingReducing particle pollution from ships, Underwater volcano eruption Increasing solar energy production.
In a A new study in natural earth sciences Japanese researchers this month are looking into how the difference in energy coming to and leaving the planet — called Earth’s energy imbalance — will increase in 2022. Scientists said greater imbalance, or more trapped heat, leads to warmer temperatures. The researchers estimate that about three-quarters of the change in Earth’s energy imbalance can be attributed to a combination of long-term human-caused climate change and the shift from a three-year cooling La Niña cycle to a warm El Niño cycle.
The El Niño phenomenon is a phenomenon of periodic and natural temperature rise in areas of the tropical Pacific Ocean that then leads to a change in weather patterns in the world, while the El Niño phenomenon is characterized by cooler than average waters.
It changes both rainfall and temperature patterns, but in different ways. El Niño tends to increase global temperatures, while La Niña tends to dampen long-term warming.
La Ninas tend to cause More damage in the United States Due to increased hurricane activity and drought, according to studies.
From 2020 to 2023, the Earth was An unusual “triple dip” of La Nina. Without the El Niño phenomenon occurring between them. In La Niña, warm water sticks deeper, resulting in a cooler surface. This reduces the amount of energy going out into space, said study co-author Yu Kosaka, a climate scientist at the University of Tokyo.
She compared it to what happens when people have a fever.
“If our body temperature is high, it tends to release its energy, and the Earth has the same situation,” Kosaka said. “As temperatures rise, it releases more energy outward. For a three-year La Niña, it is the opposite.”
More energy — which turns into heat — is trapped in the ground, she said. Kosaka said La Niña usually corresponds to the buildup of an additional energy imbalance over a year or two, but this time was longer, so the difference was more pronounced and included higher temperatures.
“When there’s a transition from La Niña to El Niño, it’s as if the lid has been opened,” which releases heat, explained Tom Di Liberto, a former meteorologist at the National Oceanic and Atmospheric Administration (NOAA), who now works with Climate Central.
About 23% of the energy imbalance driving recent warming comes from an unusually long La Niña pattern, with just over half of it coming from gases from burning coal, oil and gas, the study authors said. The rest could be other factors.
Scientist Jennifer Francis of the Woodwell Center for Climate Research, who was not involved in the study, said the research makes sense and explains the increase in energy imbalance that some scientists attribute to accelerating global warming.
For 75 years, when meteorologists calculated El Niños and La Niñas, it was based on the difference in temperatures in three tropical Pacific regions compared to the normal range. El Niño was 0.5°C (0.9°F) warmer than normal and La Niña was cooler than normal by the same amount.
The problem with a warming world is that what is considered normal continues to change.
Until now, NOAA has used the 30-year average as usual. It updates a 30-year average every decade, which is how often it updates most climate and weather measurements. After that, water temperatures warmed so much for El Niños and La Niñas that NOAA updated its definition of normal every five years, but that wasn’t enough either, said Nate Johnson, a meteorologist at NOAA’s Geophysical Fluid Dynamics Laboratory.
So NOAA has come up with a relative index for El Niño, starting this month. This new index compares temperatures to the rest of the Earth’s tropical regions. Johnson said the difference between the old and new methods recently reached up to half a degree Celsius (0.9 degrees Fahrenheit), and “that’s enough to make an impact.”
This is because what really matters in El Niños and La Niñas is the way water interacts with the atmosphere. Johnson said that recent interactions did not match the old classification, but they did match the new method.
This will likely mean more La Niña and fewer El Niño compared to the old regime, Johnson said.
The National Oceanic and Atmospheric Administration (NOAA) expects El Niño to develop later this year in late summer or fall. If this happens early enough, it could dampen hurricane activity in the Atlantic Ocean. But it also means global temperatures will rise in 2027.
“When El Niño develops, we will likely set a new global temperature record,” Woodwell’s Francis said in an email. “‘Normal’ was left in the dust decades ago. With this much heat in the system, everyone should prepare for the extreme weather that will fuel it.”
___
AP’s climate and environment coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Search for access points Standards To work with charities, list of supporters and funded coverage areas on AP.org.