HELENA — The internet and social media are abuzz with this upcoming El Niño. There is a lot of hoopla as to what could happen, but what is known is what El Niño is and how it forms.
El Niño is Spanish for "little boy", and it refers to the warming of the ocean surface in the central and eastern tropical Pacific Ocean near the equator. History suggests it was first noticed by Peruvian fishermen as fisheries were impacted beginning around Christmas.
During normal conditions in the Pacific Ocean, trade winds blow west along the equator, taking warm water from South America toward Asia. With surface water pushed west, cold water rises from the depths, a process called upwelling. During El Niño, those trade winds weaken or stop, allowing a buildup of warmer surface water in the central and Eastern Pacific. La Niña is the opposite of El Niño, and the trade winds are stronger, creating more upwelling, and colder than normal water rises to the surface. This variation has an effect on fisheries and can alter the weather in parts of the world.
What causes the trade winds to change is not known. The exact effects this will have on global weather patterns are also not explicitly known, as no two El Niños are the same. But a large natural climate pattern that shifts ocean surface temperatures across large sections of the Pacific will almost certainly create changes in some global weather.
