Which ecosystem collapse mechanism occurs in coastal South America during a strong El Niño event?

💡 Explanation

During a strong El Niño, thermocline suppression occurs because warm surface waters prevent upwelling of nutrient-rich deep water, thus reducing primary productivity. Therefore nutrient depletion causes ecosystem collapse, rather than coral bleaching (typically in tropical regions), species displacement (generally longer-term), or oxygen depletion (related to eutrophication).

• Which mechanism creates natural levees bordering a mature alluvial river?
• Which mechanism is disrupted when increased freshwater input from glacial melting slows coastal upwelling circulation?
• Which process limits thermohaline circulation if Arctic ice melt significantly increases freshwater input?
• Which mechanism creates a stratified water column within a fjord following a glacial meltwater pulse?
• Which slope stability risk increases when repeated freeze-thaw cycles affect shale bedrock underlying a tundra region with solifluction?
• Which mechanism causes liquefaction during seismic shaking in saturated granular soils?