Will Warm Water Wreak Havoc When Winds Won’t Blow?
Well, it looks like the next El Niño is coming. Right now many scientists are observing warming over the Tropical Pacific, and this has led to predictions of the next El Niño. El Niño is known to scientists as the El Niño-Southern Oscillation, or ENSO, and is a complicated chain of events that begins in the Pacific Ocean and then spreads to affect the weather around the entire world. What is the El-Niño Southern Oscillation, you ask? The El-Niño Southern Oscillation is the result of a cyclic warming and cooling of the surface ocean of the central and eastern Pacific.
In normal, non-El Niño conditions the central and eastern Pacific region of the ocean is normally colder than its equatorial location would suggest. This condition exists because of the influence of trade winds blowing to the west, a cold ocean current flowing up the coast of Chile, and upwelling of cold deep water off the coast of Peru. The trade winds blow toward the west across the tropical Pacific and these winds pile up warm surface water in the west Pacific. The sea-surface temperatures are much colder near South America because of an upwelling of cold water from deeper levels. This cold water is extremely nutrient rich, leading to high levels of primary productivity, a rich ecosystem, and major fisheries off the coast of Peru.
During an El Niño event, the trade winds weaken in the central and western Pacific for unknown reasons. This weakening causes western Pacific waters to cool, and a warming in the eastern Pacific. The warm, still surface waters in the east Pacific reduce the efficiency of the cold nutrient-rich upwelling, which results in an even larger increase in sea surface temperatures and a dramatic decline in productivity that severely impacts marine life and commercial fisheries in this area. The warming waters in the east Pacific cause huge thunderstorms and floods in the Peru area, while the cooler water temperatures in the west Pacific cause problems such as droughts in Indonesia and Australia.
In normal, non-El Niño conditions the central and eastern Pacific region of the ocean is normally colder than its equatorial location would suggest. This condition exists because of the influence of trade winds blowing to the west, a cold ocean current flowing up the coast of Chile, and upwelling of cold deep water off the coast of Peru. The trade winds blow toward the west across the tropical Pacific and these winds pile up warm surface water in the west Pacific. The sea-surface temperatures are much colder near South America because of an upwelling of cold water from deeper levels. This cold water is extremely nutrient rich, leading to high levels of primary productivity, a rich ecosystem, and major fisheries off the coast of Peru.
During an El Niño event, the trade winds weaken in the central and western Pacific for unknown reasons. This weakening causes western Pacific waters to cool, and a warming in the eastern Pacific. The warm, still surface waters in the east Pacific reduce the efficiency of the cold nutrient-rich upwelling, which results in an even larger increase in sea surface temperatures and a dramatic decline in productivity that severely impacts marine life and commercial fisheries in this area. The warming waters in the east Pacific cause huge thunderstorms and floods in the Peru area, while the cooler water temperatures in the west Pacific cause problems such as droughts in Indonesia and Australia.
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