In the coming months, Pacific Island countries can expect a barrage of rain, flooding, and higher sea levels triggered by a weather pattern that has irregularly visited their borders every two to seven years for more than 125,000 years. The phenomenon called El Niño is expected to mirror the worst recorded occurrence in 1997/98, which wreaked havoc, causing widespread destruction, severe drought, and the spread of infectious diseases from a lack of water for sanitation.
El Niño, which occurs when Pacific trade winds die out and ocean temperatures become unusually warm, is the warm phase of an oscillation called the El Niño/Southern Oscillation (ENSO).
Named by fisherman off the coast of South America, El Niño, or "the little one" in Spanish, originates in the tropical Pacific ocean-atmosphere system, and affects weather pattern variability all over the world, according to the National Oceanic and Atmospheric Administration (NOAA).
Senior climate scientists at NOAA Climate predict the pending occurrence will be "pretty strong," based on June to August average sea surface temperatures at 2.2 degree Fahrenheit (1.22 degrees Celsius) above normal, the third highest value since the records started in 1950.
Fears over its potentially devastating impact have prompted the U.N. to urge communities and governments to start preparing for the extreme weather changes usually caused by El Niño.
"El Niño has the potential to trigger a regional humanitarian emergency and we estimate as many as 4.1 million people are at risk from water shortages, food insecurity and disease across the Pacific," Sune Gudnitz, head of the United Nations Office for the Coordination of Humanitarian Affairs, Regional Office for the Pacific said in a press release.
The World Health Organization previously reported that floodwaters contaminated with human or animal waste can cause infectious diseases such as cholera, typhoid, and diarrhea. In drought conditions, there is not enough water available for washing and sanitation, which tends to increase the risk of disease.
El Niño, in particular, creates an ideal breeding ground for mosquitoes, which need access to stagnant water in order to breed. The pesky insect, which is a carrier for viral diseases, thrives after heavy rainfall. Drought conditions in normally wet regions can cause stagnation of water in rivers as well.
An abundance of mosquitoes may transmit malaria in the Pacific Islands after El Niño causes a severe change in the weather pattern.
Gudnitz stated that some countries were already feeling the impacts of the variable weather pattern with reduced rainfall affecting crops and drinking water supplies. United Nations resident coordinator, Osnat Lubrani said a number of countries were in the process of implementing or drafting drought plans. "United Nations stands ready to support these efforts by providing coordination and technical advice," he said.