AUSTIN (KXAN) – La Niña has been getting a lot of attention over the last couple of years. It’s a wily climate pattern that occurs when water in the Pacific Ocean becomes unusually cold near the equator, it can cause Texas winters to become warmer and drier. La Niña also heightens fears of a dangerous drought.
La Niña has a sibling. A naughty, sticky little brother who has been in time out, El Niño. Recent research conducted by the University of Texas at Austin suggests El Niño is getting stronger and occurring more frequently. This could be bad news for Texas.
“It’s a big climate event that happens every two to seven years. Every place that borders the Pacific Ocean, which is like half the planet gets impacted by El Niño,” says Jud Partin, Ph.D., a research scientist with UT.
El Niño is the opposite of La Niña in many ways. It still impacts Texas in the winter months but is caused by unusually warm temperatures in the Pacific Ocean near the equator. A strong El Niño causes Texas winters to be wetter and colder.
El Niños are getting stronger
Partin said that over the last 40 years, we’ve had several strong El Niño events. He and researchers with the University of Texas wanted to know what the cause was and if climate change plays a role.
To track how El Niño is changing, the team looked at El Niños from thousands of years ago. To study these ancient climate patterns, they relied on ancient undersea coral.
“They’re like little windows, little snapshots of time for when the coral grew. And it could be anywhere from hundreds of thousands of years ago.” By studying the chemical make up of coral, they can determine the water temperature and salinity, amount of salt, the ocean contained. This allowed them to track when El Niños occurred and the strength of the El Niño.
They found that for 9,000 years, El Niños were weaker and occurred less frequently.
What is causing El Niño to change?
Partin said that natural changes in the Earth’s orbit and climate are the primary reason El Niño is getting stronger. To determine this, they had to track the changes in the pattern over hundreds of years. Tracking individual patterns would mess up their data because El Niño events vary in strength from event to event.
Because it takes such a large time frame to track changes in El Niño, determining the role humans are having is difficult. Human-driven climate change has only been a thing in the past 200 years. It takes 500 years worth of El Niño events to track a pattern.
How ancient El Niños can help us predict climate change
This data isn’t going to waste. Researchers will be able to use it to test climate models, by having those models predict past climate events, like El Niño and La Niña.
“Can the model get that right? Back in time? If so we’ll have more confidence in its projections for the future,” Partin said.
If they can predict the past, these models can better help us predict the future and the antics of a pair of sneaky climate siblings.
