Climate change and El Niño: 'Likely' breach of key global warming threshold by 2027

The coming weather pattern is expected to "push global temperatures into uncharted territory," WMO Secretary-General Prof. Petteri Taalas said.

A forest fire burns in Brazil's Amazon basin
A forest fire burns in Brazil's Amazon basin, Aug. 25, 2016. (Vinicius Mendonca/IBAMA via AP, File)

The imminent arrival of an El Niño weather event will cause global temperatures to breach the critical 1.5 degree Celsius threshold by 2027, a report issued this week from the World Meteorological Organization (WMO) found.

“A warming El Niño is expected to develop in the coming months and this will combine with human-induced climate change to push global temperatures into uncharted territory,” WMO Secretary-General Petteri Taalas said in press release. “This will have far-reaching repercussions for health, food security, water management and the environment. We need to be prepared.”

What is an El Niño?

Flooding in Villa Paranacito, Argentina
Flooding in Villa Paranacito, Argentina, April 28, 2016. (Natacha Pisarenko/AP)

According to the National Oceanic Atmospheric Administration (NOAA), El Niño periods are characterized by a weakening of trade winds across the Pacific. "Warm water is pushed back east, toward the west coast of the Americas," the NOAA states on its website. That results in warmer temperatures and dryer air across much of Canada and the United States. Due to shifts in the jet stream, however, the southern U.S., may experience wetter than usual conditions.

Why does 1.5°C of global warming matter?

A factory in Ahmadabad, India, emitting smoke
A factory in Ahmadabad, India. (Ajit Solanki/AP)

In 2018, the United Nations Intergovernmental Panel on Climate Change issued its landmark report titled “Global Warming of 1.5°C” that was compiled by hundreds of the world's leading climate scientists. It warned of catastrophic consequences linked to crossing that level of global warming, including drought, crop failure, deadly heat waves, melting polar ice caps and sea level rise, extreme rainfall events and much more.

Since then, numerous studies have concluded the planet is on course to exceed 2°C of warming.

“In many regions, warming has already surpassed 1.5 degrees Celsius above pre-industrial levels. More than one-fifth of all humans live in regions that have already seen warming greater than 1.5 degrees Celsius in at least one season,” NASA states on its website.

April marked the 530th consecutive months of hotter-than-normal temperatures in comparison to the 20th century average, according to data from the NOAA.Yet the WMO cautioned in its study that crossing the global temperature average by 1.5°C did not mean that the goal of keeping global warming below that level was lost.

“This report does not mean that we will permanently exceed the 1.5°C level specified in the Paris Agreement which refers to long-term warming over many years,” Taalas said in a press release. “However, WMO is sounding the alarm that we will breach the 1.5°C level on a temporary basis with increasing frequency.”

The costs of El Niño

Flooded homes after heavy rains inundated the region around Hammond, La.
Flooded homes after heavy rains inundated the region around Hammond, La. (Max Bevhrer/AP)

A study published Thursday in the journal Science found that the costs incurred during El Niño events are much higher than previously estimated.

"Study authors said the average El Niño costs the global economy about $3.4 trillion. The strong 1997-1998 one cost $5.7 trillion," Yahoo News partner the Associated Press reported.

With the arrival of a strong El Niño, the last of which occurred in 2016, the chances of crippling droughts and life-threatening heat waves rise dramatically. To date, global temperatures have risen approximately 1.2°C since the dawn of the Industrial Revolution, with the bulk of that warming coming in the last few decades as greenhouse gases continue to build up in the Earth’s atmosphere. A strong El Niño, the report warns, could push temperatures to even greater extremes.