Explain El Niño, how it's identified, and it's potential negative impacts.

I know this is a lot : This might not have negative impacts:

El Niño is a natural phenomenon experienced in the equatorial Pacific which causes temporary alterations in the world climate. It is normally characterized by complex and abnormally warm ocean temperatures in the Pacific Ocean in the area near the equator which results in global weather events and sea-surface temperature changes.

In practical sense, the ocean surface around the equator region warms up by small degrees Celsius along with very heavy thunderstorms. The small rise in temperatures is influenced by change in the normal wind direction. Scientist also prevails that the temperature increases may be intensified by the effects of greenhouse gases and consequent global warming. This small difference in temperature increase has a substantial impact on the world's climate.

In normal conditions, the wind blow from the east to the west along the equator in the Pacific. These are the trade winds which blow towards the west along the equator. This results in the piling of water in the western side of the Pacific to a sea surface area of up to 18 inches high.

In the eastern side, deeper water (which is cooler compared to the sun-heated warm surface water) gets pulled up from beneath to substitute the water pushed to the west. So, the normal difference in temperature across the equatorial Pacific is cold water (about 22 degrees Celsius) in the east and warm water (about 30 degrees Celsius) in the west.

In El Niño conditions, the winds propelling the water get weaker and as an outcome, some of the warm water collected in the west is heavily drawn towards the east. At the same time, not so much cold water is pulled up from beneath. Accordingly, these elements make the water in the pacific warmer which results in El Niño events.

Drastic Effects of El Niño

Effect on aquatic species and sea birds

In normal situations, the ocean water carry nutrients that lie beneath the ocean to the top thereby allowing the fish species living in the upper waters to feed on the planktons that rely on these nutrients. Seaweeds also rely on cool and nutrient-rich water for survival and growth. An El Niño lessens the upwelling of cold water and the uplift of nutrients from the bottom of the ocean.

As a result, fish either migrate to other regions or die during an El Niño because they lack adequate food for growth and survival. When fish have migrated or reduced in number, other aquatic creatures namely the sea birds and seals that feed on the fish are also affected. Off the coast of California, the aquatic populations such as fish, seals, sea lions, and sea birds are normally affected and deaths are registered during El Niño events.