Final answer:
An El Niño event disrupts the upwelling process, which brings nutrient-rich cold water to the surface. This disrupts the marine food chain, reducing fish populations and impacting the fishing industry in Peru and Ecuador. The effects are dramatic and long-lasting on local human populations that rely on fishing.
Step-by-step explanation:
An El Niño event is a period of unusual warming of the surface waters in the eastern tropical Pacific, which disrupts weather patterns around the globe. Specifically, in countries like Peru and Ecuador, the warmer ocean temperatures interfere with the normal upwelling process. This upwelling typically brings nutrient-rich cold water to the surface, supporting vast populations of phytoplankton which are a vital part of the marine food chain, providing food for a wide range of sea creatures including fish.
No upwelling means less nutrients, leading to a drop in phytoplankton populations. This, in turn, impacts the food chain resulting in a decline in fish populations, affecting the fishing industry. Additionally, other marine species not directly linked to the fishing industry, such as seabirds, also get affected due to the lack of food, and this has a broader impact on the overall marine ecosystem.
The coastal communities that rely heavily on fishing for their livelihoods suffer both from reduced catches and from the social and economic knock-on effects. For example, fishery extinctions rarely lead to complete extinction of the harvested species, but rather to a radical restructuring of the marine ecosystem in which a dominant species becomes a minor player, ecologically. This collapse of fisheries has dramatic and long-lasting effects on local human populations that work in the fishing industry. The loss of an inexpensive protein source to populations that cannot afford to replace it can also increase the cost of living and limit societies in other ways.
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