Which mechanism significantly reduces surface salinity in areas of intense oceanic upwelling?

💡 Explanation

When upwelling occurs, vertical advection brings deep water to the surface because density differences drive the circulation, reducing surface salinity because the deeper ocean layers often contain fresher water from glacial melt or river outflow. Therefore, deep water entrainment results, rather than evaporation, ice, or productivity effects which would increase surface layer concentration.

• Which effect occurs when sustained offshore winds drive coastal upwelling of nutrient-rich water?
• Which phenomenon causes offset landforms and frequent shallow earthquakes parallel in a transform plate boundary?
• Which mechanism causes localized uplift along a strike-slip fault segment during an earthquake?
• Which mechanism causes buoyant magma to ascend during intraplate volcanism?
• Which risk increases upon permafrost thaw affecting ice within rock fractures?
• Which outcome primarily results when coastal upwelling brings deep ocean water to the surface?