Which mechanism reduces primary productivity in the eastern Pacific Ocean during an El Niño event?

💡 Explanation

During El Niño, weakened trade winds cause a reduction in the intensity of equatorial upwelling because surface warm layer thickens, suppressing upward nutrient transport, ultimately impacting primary productivity. Therefore, weakened equatorial upwelling results, rather than just increased thermocline depth etc, as upwelling mechanically dictates nutrient availabilty.

• Which risk increases during the earthquake cycle phase known as the interseismic period at a subduction zone?
• Which slope failure risk escalates significantly on high-latitude construction sites with thawing permafrost?
• Which atmospheric effect results when the descending air from a Hadley cell warms adiabatically near 30 degrees latitude?
• Which flow regime occurs when oceanic upwelling weakens?
• Which mechanism amplifies volcanic explosivity when magma ascending through a subduction zone encounters groundwater near the surface?
• Which consequence results when increased trade wind intensity enhances coastal upwelling?