Past and Future El Nino Ghosts Haunting Climate
Climate change may be making El Niño (“The Child” in Spanish) hyperactive. But scientists disagree if we can know that the boy is going to be a brat a year beforehand.
Climate scientists found evidence that El Niño became more active during the late 20th century, and that people may have been the ones giving the kid sugar in the form of greenhouse gases. This conclusion came from studying a combination of ancient tree rings and volcanoes.
Climate scientists examined more than 2,000 tree ring records from trees growing over a 700 year period from the tropics as well as the higher latitudes in both the northern and southern hemispheres.
“The inclusion of tropical records enables us to achieve unprecedented accuracy,” wrote the authors of the study, which was published in Nature Climate Change.
The rings left records of El Niño’s past. Trees grow wider rings during years with warmer, wetter weather, so these tree rings provided a chronology of climate stretching back to when Dante’s Inferno was on the new releases shelf. This study of tree rings is known as dendrochronology.
The tree ring records suggested that ancient volcanic eruptions affected the El Niño cycle. The records also found similar affects on El Niño in 20th century, although no volcanic activity explained the abnormal behavior of El Niño.
“In the year after a large tropical volcanic eruption, our record shows that the east-central tropical Pacific is unusually cool, followed by unusual warming one year later,” said lead author Jinbao Li of the University of Hong Kong in a press release. “Like greenhouse gases, volcanic aerosols perturb the Earth’s radiation balance. This supports the idea that the unusually high ENSO activity in the late 20th century is a footprint of global warming.”
“Many climate models do not reflect the strong ENSO response to global warming that we found,” said co-author Shang-Ping Xie, meteorologist at the International Pacific Research Center, University of Hawaii at Manoa. “If this trend of increasing ENSO activity continues, we expect to see more weather extremes such as floods and droughts.”
Despite the complex human and natural influences on El Niño, another recent study claims to have found a means of forecasting an El Niño one year ahead of time, but not every scientist is ready to lay their bet on the predictions.
El Niño and his sister, La Niña, together go by the family name El Niño Southern Oscillation (ENSO). Variations between these events can wither crops in one part of the world, while flooding another. Being able to predict this would save lives and crops.
A new study published in the Proceedings of the National Academy of Sciences presented a means of predicting an El Niño up to a year before the Child has his tantrum.
However, USA Today reported that some climate scientists doubt the ability to forecast beyond the six-months currently reported by the National Oceanic and Atmospheric Administration.
“I’m very skeptical. I don’t think this is a breakthrough,” El Niño forecaster Anthony Barnston of Columbia University’s International Research Institute for Climate and Society told USA Today.
Strong winds whip thick clouds of dust across the Bolivian highlands during an El Niño. (NASA Earth Observatory, Wikimedia Commons)
ENSO affects in northern and southern hemispheres. (National Oceanic and Atmospheric Administration, Wikimedia Commons)