Question

________ __________________ is a mixing action that occurs in some estuaries at high tide due to seawater at the surface moving upstream more quickly than bottom water from the river.

Answer 1

Ocean upwelling is a mixing action that occurs in some estuaries at high tide, where seawater at the surface moves upstream more quickly than bottom water from the river. It brings nutrient-rich waters from the deeper parts of the ocean to the surface, supporting the growth of phytoplankton and triggering the productivity of marine ecosystems.

Step-by-step explanation:

The mixing action that occurs in some estuaries at high tide, where seawater at the surface moves upstream more quickly than the bottom water from the river, is called ocean upwelling. Ocean upwelling is the rising of deep ocean waters that happens when prevailing winds blow along surface waters near a coastline. This process brings nutrient-rich waters from the deeper parts of the ocean to the surface, supporting the growth of phytoplankton and triggering the productivity of marine ecosystems.