What might prevent an upwelling from occurring and affect coastal villages that rely on fish for survival?

surface currents
El Niño
too much wind
the Coriolis effect

El Niño events might prevent an upwelling from occurring and affect coastal villages that rely on fish for survival. During El Niño, the trade winds which normally blow from east to west weaken or even reverse, causing a decrease in the upwelling of nutrient-rich water near the coast. This can lead to a decline in fish populations, affecting the livelihoods of coastal communities.