El Nino likely to form in coming months, raise global heat risk: China climate center

A new El Nino event, a climate phenomenon marked by warmer-than-average sea surface temperatures in the central and eastern equatorial Pacific, is likely to develop in the coming months and could reach moderate or stronger intensity later this year, raising the risk of higher global temperatures and more extreme weather.

Recent monitoring shows sea surface temperatures in the central and eastern equatorial Pacific are continuing to rise, a key signal that the climate pattern is developing, the National Climate Center said.

The Pacific Ocean is expected to enter El Nino conditions around May, with a moderate or stronger event forming during the summer and autumn and lasting at least until the end of the year, it added.

Recent online discussions claiming that the world could experience the strongest El Nino in 140 years and potentially record-breaking global heat have attracted widespread public attention.

However, Chen Lijuan, chief forecaster at the center, said it is still too early to conclude that global temperatures will break records this year.

"Considering the lagging effect of El Nino, it is premature to say that the Earth will hit a new heat extreme this year. But the related risks are clearly increasing," Chen said.

El Nino events occur when sea surface temperatures in parts of the tropical Pacific become much warmer than normal. The warming allows large amounts of heat stored in the ocean to be released into the atmosphere, raising global temperatures.

When such warming occurs on top of the long-term trend of global warming, it can make heat waves more frequent, intense and longer lasting, according to the center.

The full warming effect of El Nino often appears with a delay and typically peaks the following year. "The possibility of record-breaking heat cannot yet be determined for the current year," Chen said.

Wang Yaqi, a senior engineer at the National Climate Center, said stronger El Nino events can have broader impacts on the economy, energy systems and public health, as they are often associated with extreme heat, droughts and heavy rainfall.

Intense rainfall during strong El Nino events can trigger flooding that forces some hydropower stations to reduce output or suspend operations, while drought conditions may sharply cut electricity generation.

In the health sector, changes in rainfall and temperature patterns linked to El Nino can increase the spread of some infectious diseases. Drought and extreme heat also raise the risk of wildfires, Wang said.

The risks linked to El Nino are not driven by the climate pattern alone. They often emerge from the interaction of multiple climate factors, with El Nino acting as a "trigger" within a broader system influenced by global warming.

It is estimated that for every 1 C increase in atmospheric temperature, the air's capacity to hold moisture rises by about 7 percent, which means higher temperatures can accelerate evaporation and intensify droughts, while also increasing the likelihood of extreme rainfall and flooding when precipitation occurs.

The combination of background global warming and El Nino-driven warming could increase the chances of compound extreme weather events, including more intense heat waves and sudden shifts between drought and heavy rainfall, Wang said.