El Niño conditions have developed in the tropical Pacific for the first time in seven years, setting the stage for a likely surge in global temperatures and disruptive weather and climate patterns this year and in 2024. The naturally occurring major climate phenomenon may aggravate current humanitarian crises around the world and may lead to new emergencies related to the ongoing climate crisis.
A new update from the World Meteorological Organization (WMO), based on expert guidance from around the world, forecasts that there is a 90 percent probability of the El Niño event continuing during the second half of 2023. It is expected to be at least of moderate strength.
“The onset of El Niño will greatly increase the likelihood of breaking temperature records and triggering more extreme heat in many parts of the world and in the ocean,” WMO Secretary-General Prof. Petteri Taalas said today.
“The declaration of an El Niño by WMO is the signal to governments around the world to mobilize preparations to limit the impacts on our health, our ecosystems and our economies,” he said.
“Early warnings and anticipatory action of extreme weather events associated with this major climate phenomenon are vital to save lives and livelihoods.”
El Niño occurs on average every two to seven years, and episodes typically last 9 to 12 months. It is a naturally occurring climate pattern associated with warming of the ocean surface temperatures in the central and eastern tropical Pacific Ocean. But it takes place in the context of a climate changed by human activities.
In anticipation of the El Niño event, a WMO report released in May predicted that there is a 98 percent likelihood that at least one of the next five years, and the five-year period as a whole, will be the warmest on record, beating the record set in 2016 when there was an exceptionally strong El Niño.
The WMO report in May, led by the United Kingdom’s Met Office with partners around the world, also said there is a 66 percent likelihood that the annual average near-surface global temperature between 2023 and 2027 will temporarily be more than 1.5 °C above pre-industrial levels for at least one year.
“This is not to say that in the next five years we would exceed the 1.5 °C level specified in the Paris Agreement because that agreement refers to long-term warming over many years”, said WMO Director of Climate Services Prof. Chris Hewitt.
“However, it is yet another wake up call, or an early warning, that we are not yet going in the right direction to limit the warming to within the targets set in Paris in 2015 designed to substantially reduce the impacts of climate change.”
According to WMO, 2016 was the warmest year on record because of the “double whammy” of a very powerful El Niño event and human-induced warming from greenhouse gases. The effect on global temperatures usually plays out in the year after its development and so will likely be most apparent in 2024.
The average global temperature in 2022 was about 1.15 °C above the 1850-1900 average because of the cooling triple-dip La Niña.
El Niño events are typically associated with increased rainfall in parts of southern South America, the southern United States, the Horn of Africa and Central Asia. In contrast, El Niño can also cause severe droughts over Australia, Indonesia, parts of South Asia, Central America and northern South America.
El Niño’s warm water can fuel hurricanes in the central and eastern Pacific Ocean, while it could hinder hurricane formation in the Atlantic Basin. Generally, El Niño has the opposite effect of the recent La Niña, which ended earlier in 2023.
Meanwhile, the World Health Organization (WHO) said Tuesday - noting the very high probability that 2023 and 2024 would be marked by El Niño events - it was particularly concerned about food insecurity and increase in moderate and acute malnutrition, especially amongst the most vulnerable people.
The UN agency also expressed concerns over potential increase in water-borne diseases such as cholera due to water scarcity or flooded water and sanitation infrastructure. An increased number of people could be affected by infectious diseases such as measles and meningitis, especially in acute humanitarian situations.
WHO said it was reasonable to expect an increase in infectious diseases because extreme weather events were more frequent and intense. El Niño’s could also lead to a disruption of health services due to lack of water supply in drought situations or damage to health infrastructure by floods and cyclones, as well as extreme heat and an increased risk of wildfires.
Regarding the vulnerable geographical areas, the World Health Organization is mainly looking at Africa, Latin America, South and South-East Asia. Regarding ongoing humanitarian crises, the Sahel region, the Horn of Africa, Pakistan and Myanmar could be particularly affected.
The World Meteorological Organization (WMO) is an intergovernmental organization with a membership of 193 Member States and Territories. Established on 23 March 1950 and specialized in meteorology (weather and climate), operational hydrology and related geophysical sciences, the United Nations agency is headquartered in Geneva.
The World Health Organization (WHO) is a specialized agency of the United Nations based in Geneva. The purpose of the organization is to coordinate the international public health system. The WHO's official mandate is to promote health and safety while helping the vulnerable worldwide. Founded on April 7, 1948, WHO today has 194 member states.
Further information
Full text: World Meteorological Organization declares onset of El Niño conditions, World Meteorological Organization (WMO), press release, published July 4, 2023
https://public.wmo.int/en/media/press-release/world-meteorological-organization-declares-onset-of-el-ni%C3%B1o-conditions