El Ninos getting stronger due to climate change, study finds
A new study has found that El Ninos are becoming stronger as human-caused climate change warms the planet. Researchers said El Nino events are now more than 36% stronger than before the industrial era, with the increase accelerating in recent decades.
Washington: A new study suggests that El Ninos – the natural climatic chaos agent that pops up periodically and spikes global temperatures – are getting stronger because of human-caused climate change.
El Ninos are more than 36% stronger than they were before the industrial age began in the mid 1800s, with a 16% jump in just the last 40 years showing that the increase is accelerating, according to a study in Thursday’s journal Science.
The findings come as a strong El Nino that formed a couple months ago is forecast to be the biggest on record in coming months. El Ninos, which are a temporary warming of parts of the equatorial Pacific, warp weather worldwide and increase extreme events, including heat waves, floods in some places and droughts in others. They can cost trillions in damage.
“That’s important because strong El Ninos have much stronger impacts on climate hazards and extremes worldwide. When we set out to answer the question of why this might be happening, we set our data up against a record of global temperature, and we found that the increase in El Nino’s strength closely parallels the rise in global temperature that is due to human causes such as the burning of fossil fuels,” said study lead author Julia Cole, a paleoclimate scientist at the University of Michigan.
Her study looks back at El Ninos going back 900 years or so.
“El Nino is the most violent aspect of climate variability worldwide, with effects ranging from local fisheries collapse, to widespread coral die-offs to severe droughts and food shortages around the world,” said Dalhousie University marine scientist Boris Worm, who wasn’t part of the study.
Worm quoted the late climate scientist Wallace Broecker who warned “the climate system is an angry beast and we are poking it with sticks.” And then Worm added: “Human emissions are the stick and El Nino is of the angry’ outbursts that can be so threatening to our collective safety.” An El Nino’s strength is determined by measuring water temperature in a region of the central Pacific around the equator and comparing a three-month average to normal.
If it’s 0.5 degrees Celsius (0.9 degrees Fahrenheit) warmer than normal, it’s becomes an El Nino.
The top of the scale is 2 degrees Celsius (3.6 degrees Fahrenheit) and is called “very strong”. The most recent weekly El Nino figure is at 2.7 degrees (4.9 degrees Fahrenheit) and is expected to keep growing for another two to four months, according to Columbia University’s El Nino tracker.
Scientists have long theorised that as the world warms, El Ninos would get stronger because they are based on ocean temperature differences compared to average. But observational records only goes back about 75 years, so scientists have previously said the data is too spotty for a trend.
So scientists have looked for clues that indicate an El Nino without measuring water temperatures directly.
Scientists, for example, have looked back at historical records of changes in weather around the world and figured out past El Ninos – such as the super-sized one in 1877 – due to the changes they cause across the globe.
