Which impact occurs on global nutrient distribution due to El Niño?

💡 Explanation

El Niño suppresses upwelling off South America due to weakened trade winds, leading to warmer surface waters; this causes reduced nutrient availability because nutrient-rich deep water doesn't reach the surface and supports fisheries, therefore A rather than B/C/D.

• Which risk intensifies as alluvial river plains subside?
• Which changes due to increased stratification limit upwelling?
• Which geological outcome occurs when sustained, unidirectional wind interacts with unconsolidated desert sediment?
• Which outcome promotes stack collapse during storm surges?
• Which mechanism primarily causes stratovolcanoes to exhibit explosive eruptions with significant pyroclastic flow?
• Which outcome increases when constructed river levees cause channel incision?