“La Niña is a natural climate phenomenon that brings cooler ocean temperatures, impacting global weather patterns and leading to extreme events like floods and droughts.”—Sande Melo of facts.net
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Following the extreme heat experienced last year due to the El Niño phenomenon, it is anticipated that excessive rainfall and flooding in the coming months will occur as a result of La Niña.
These unlikely weather events are expected to persist until the end of March, according to the Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA)
“Higher chances of above normal rainfall in January, February, March 2025 season is expected, which may cause floods, flash floods and rain-induced landslides,” the country’s weather bureau said in a statement.
During the period, there is an increased chance of tropical cyclone activity within the Philippine Area of Responsibility (PAR). Approximately 20 typhoons are entering our country each year.
The names of this year’s typhoons are Auring, Bising, Crising, Dante, Emong, Fabian, Gorio, Huaning, Isang, Jacinto, Kiko, Lannie, Mirasol, Nando, Opong, Paolo, Quedan, Ramil, Salome, Tino, Uwan, Verbena, Wilma, Yasmin, and Zoraida.
The auxiliary names include Alamid, Bruno, Conching, Dolor, Ernie, Florante, Gerardo, Hernan, Isko, and Jerome. These are used only when more than 25 typhoons hit the country before the year ends.
According to PAGASA, La Niña conditions are expected to persist during the January to March months, “as suggested by several climate models.”
“Periods of cooler-than-average sea surface temperatures in the equatorial Pacific Ocean that started in September 2024 continue to persist and further strengthened reaching the La Niña conditions threshold in December 2024,” the weather agency added.
A La Niña condition is recognized when a one-month sea surface temperature anomaly (SSTA) of -0.5°C or lower, along with a three-month SSTA of -0.0°C or lower, is observed.
Heavy rains and floods are two symptoms of La Niña. It is the exact opposite of the phenomenon called El Niño, which means “the Little Boy” or “Christ Child” in Spanish. La Niña, on the other hand, means “the Little Girl.” It is sometimes called “El Viejo,” “anti-El Niño,” or simply “a cold event” or a cold episode.
Scientists say El Niño and La Niña occur every two to seven years and typically last for 9 to 12 months. Dr. Kevin Trenberth, an American distinguished senior scientist at the National Center for Atmospheric Research in Boulder, Colorado, warned: “El Nino extremes are greater, while La Nina lasts longer.”
To simplify, meteorologists explain: El Niño and La Niña are opposite phases of the ENSO cycle, with La Niña sometimes referred to as the cold phase of ENSO and El Niño as the warm phase of ENSO.
“El Niño and La Niña result from interaction between the surface of the ocean and the atmosphere in the tropical Pacific,” the US National Oceanic and Atmospheric Administration (NOAA) explained. “Changes in the ocean impact the atmosphere and climate patterns around the globe. In turn, changes in the atmosphere impact the ocean temperatures and currents.”
In the tropics, global climate variations in La Niña tend to be opposite of those of El Niño.
“If you expect drought in the country with El Niño because of reduced rainfall and less typhoons, there will be more than normal rainfall and the normal but ‘stronger typhoons’ during a La Niña episode that will cause floods and devastation of farms and property,” explains Dr. Rafael D. Guerrero III, an academician at the National Academy of Science and Technology.
With La Niña, typhoons are expected to be more common and disastrous. “Potential adverse impacts of the developing La Niña include floods and landslides over vulnerable areas with varying magnitude,” the weather bureau warned.
“All concerned agencies are advised to take precautionary measures to mitigate the potential adverse impacts of the developing La Niña,” urged Dr. Vicente B. Malano, PAGASA administrator. “(We) will closely monitor these conditions and regular updates and advisories shall be issued as appropriate.”
Dr. Guerrero admitted that Filipino farmers cannot do anything against the onslaught of La Niña except to prepare and plan for it. “Planting in flood-prone areas should be avoided to avert crop losses,” he stressed. “Drainage and flood-control structures should be renovated beforehand.”
Health-wise, people are likely to suffer from La Niña. During floods, food-borne and water-borne diseases accelerate, according to the Department of Health (DOH). “Flooding can contaminate the public water through the disruption of water purification and sewage disposal systems, rupture of underground pipelines and storage tanks,” said the disaster management unit of DOH.
