Sea surface anomalies across the world in July 2023 during the 2023–2024 El Niño event.
Meteorological history
Formed
June 2023
Dissipated
April 2024
Overall effects
Damage
$75 billion
Areas affected
The Pacific Ocean and surrounding areas
The 2023–2024 El Niño was regarded as the fourth-most powerful
El Niño–Southern Oscillation events in recorded history, resulting in widespread droughts, flooding and other natural disasters across the globe. The onset was declared on 4 July 2023 by the
World Meteorological Organization (WMO)[1][2][3][4] It is estimated that the most significant meteorological effects will occur between November 2023 and April 2024[5] and their characteristics will be determined depending on each territory on the planet,[6] within which
droughts, heavy rains,
wildfires,
heat waves,
tropical cyclones,
flooding and changes in wind patterns.[1][7][8] These events have already negatively affected the economic activities of agriculture and fishing, generating shortages and rising prices of food—especially
rice,
palm oil,
sugar cane,
soybeans and
corn—and, therefore, an increase in food insecurity of the most vulnerable populations.
Climate scientists say the 2023–24 El Niño event, exacerbated by the
climate change crisis,[8][9][10] will likely raise average global temperatures beyond the record set in
2016—during the
2014-2016 El Niño event—and will set new records for temperature in 2024, exceeding the 1.5 °C increase since pre-industrial times.[6][11]
Background
El Niño is a natural climate event caused by the Southern Oscillation, popularly known as El Niño or also in meteorological circles as
El Niño-Southern Oscillation or ENSO,[6] through which global warming of the eastern equatorial Pacific Ocean results in the development of unusually warm waters between the coast of
South America and the
International Date Line. This phenomenon significantly affects the global average surface temperature of the planet. A large El Niño event can raise it by as much as a few tenths of a degree Celsius.[12]
Meteorological progression
During an El Niño event, the east–west trade winds die, generating warmer air temperatures in the eastern and central parts of the tropical Pacific.[13] Warmer temperatures lead to warming ocean surface temperatures, leading to heavier rainfall and flooding in the eastern Pacific.[14][15] Since there are no trade winds, the necessary rains do not form in the western Pacific, generating droughts in Asia and Oceania.[8] The phenomenon has a recurrence of between 2 and 7 years, and can last from 9 to 12 months.[7][16]
The combination of El Niño and above-normal temperatures in the Atlantic Major Development Region (MDR) tends to favor increased hurricane activity in the eastern Pacific.[17]
At the beginning of the year, it was considered that the climatic conditions of the first quarter of 2023 pointed to the occurrence of a strong El Niño event, similar to those that occurred in 1982, 1997, and 2015.[18][19] In mid-January 2023, weather forecasts regarding the probable occurrence of the El Niño phenomenon in 2023 and 2024 were published in various media.[20][21][22] Given that Earth's average temperature has already increased by 1.2 °C since pre-industrial times, a large enough El Niño event in 2023-2024 could even push the planet, temporarily, into warming greater than 1.5 °C.[11][23][24][2]
Timeline
June 2023
July 2023
August 2023
September 2023
October 2023
November 2023
December 2023
January 2024
February 2024
March 2024
By early March 2024, pockets of below average Sea Surface Temperature SST Anomalies pierced the surface in the equatorial East Pacific, a clear sign that the El Niño event was in full retreat.[25]
Several severe thunderstorms bringing high winds and pea-sized hail hit Los Angeles, California, causing strong flooding in streets.[26]
Compared to previously strong El Niño events like
1982–83,
1997–98, and
2014–16, tropical cyclone activity in the
North Atlantic was not suppressed much by the strong El Niño due to record warm sea surface temperatures in the Atlantic.[29][30] The 2023 season went on to become the fourth most active Atlantic Hurricane season on record tied with
1933, and set an all time record high number of storms for an El Niño year.[31] North Pacific tropical cyclone activity was more mixed. The
North East Pacific was above average in terms of hurricanes, major hurricanes, and
ACE, typical of previously strong El Niño event years, despite an exceptionally late start.[32][33][34] The
North West Pacific on the other hand observed well below average activity, mostly due to a consistently negative
PDO environment, which suppressed the formation of a lot of tropical storms.[35] While the activities in the North Pacific basins were a mixed bag, both basins proved to be extremely destructive in 2023, with
Typhoon Doksuri in the North West Pacific and
Hurricane Otis in the North East Pacific both causing more than $10 billion in damages.[36][37]
Impact
Australia
North America
South America
Asia
In April 2024, the
India Meteorological Department (IMD) warned of heatwave conditions for 10 to 20 days in several parts of the country. The IMD said that the conditions would eventually subside with the onset of the
neutral phase of the El Niño–Southern Oscillation and the
monsoon in June.[38]