Which of the following is not possibly associated with the occurrence...
El Niño is the warm phase of the El Niño–Southern Oscillation (ENSO) and is associated with a band of warm ocean water that develops in the central and east-central equatorial Pacific, including the area off the Pacific coast of South America. Option a is correct. El Niño is accompanied by warmer waters in the Eastern Pacific ocean and comparatively cooler waters in western Pacific.
This results in high air pressure in the western Pacific and low air pressure in the eastern Pacific. Option b is correct. During El Nino, severe droughts occur in Australia, Indonesia, India and southern Africa. High air pressure in the western Pacific is the cause behind Australian droughts in El Nino conditions. Option c is correct. Increased concentration of Carbon Dioxide in the atmosphere has caused global warming and impending climate change.
IPCC in its multiple reports has found increased frequency and intensity of El Nino phenomena caused by Global warming. Option d is incorrect. The warmer waters during El Nino, have a devastating effect on marine life existing off the coast of Peru and Ecuador. Fish catches off the coast of South America are lower than in the normal year as the upwelling stops, reducing the supply of fresh nutrients to marine life.
Which of the following is not possibly associated with the occurrence...
El Nino Phenomena and its associations
El Nino Phenomena refers to the warming of the ocean surface in the central and eastern tropical Pacific Ocean. This warming usually occurs around Christmas time, hence the name El Nino, which means "the Christ child" in Spanish. El Nino can significantly affect weather patterns across the globe. Some of the possible associations of El Nino are:
a) High air pressure in the western Pacific and low air pressure in the eastern Pacific: During El Nino, the trade winds weaken or reverse, causing warm water to move eastward. This movement of warm water causes low air pressure in the eastern Pacific and high air pressure in the western Pacific.
b) Occurrence of droughts in Australia: El Nino can cause a shift in the location of the Pacific Ocean's warm water, leading to a significant reduction in rainfall in Australia. This can result in droughts, bushfires, and crop failures.
c) Increased concentration of Carbon Dioxide in the atmosphere: El Nino can cause a reduction in the uptake of carbon dioxide by plants and oceans. This can result in an increase in the concentration of carbon dioxide in the atmosphere, leading to global warming.
d) Improved fish production off the South American Pacific Coast: El Nino can cause an increase in the production of phytoplankton, which is the primary food source for fish. This can result in an increase in fish production off the South American Pacific Coast.
Conclusion
Improved fish production off the South American Pacific Coast is not possibly associated with the occurrence of El Nino Phenomena. Instead, El Nino can cause a reduction in fish production due to the displacement of fish populations and a decrease in the availability of food sources for fish.
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