Which impact on South American fisheries results when El Niño-Southern Oscillation (ENSO) reduces coastal upwelling?

💡 Explanation

When ENSO reduces coastal upwelling off South America, nutrient supply to surface waters decreases because cold, nutrient-rich waters are not drawn up from the deep, inhibiting phytoplankton growth and disrupting the food web. Therefore, a decline in commercially valuable fish populations results, rather than species shifts or productivity increases which require nutrient abundance.

• Which mechanism increases stream discharge during intense orographic precipitation events?
• Which outcome occurs when a rapidly eroding mountain range deposits sediment onto a flat plain?
• Which phenomenon disrupts coastal upwelling when intensified ocean gyre circulation creates strong downward Ekman transport?
• Which consequence results when thermokarst destabilizes Arctic infrastructure?
• Which phenomenon causes increased coastal aridity when intensified subtropical gyre circulation upwells cold water?
• Which outcome occurs when a mid-latitude cyclone intensifies, disrupting normal Hadley cell circulation?