Question

explain the negative. and positive causes of ocean currents

Answer 1

It regulates the global temperature. It gives free navigation.

The north eastern arm of Gulf Stream keeps ports & harbours of Russia & Scandinavia navigable through out the year.

It distributes minerals & pollution added to it becomes highly diluted & later negligible.

It helps in growth of juveniles of certain fish & its distribution to other countries - from its place of origin.

It allows sustenance of plankton & susequent fish population - for e.g Anchovetta forms the largest fish landings due to Benegula current.

The Kuroshio current makes ports on Japan navigable during winter.

Some up wellings & down wellings are due to currents which bring minerals to photic zone used by phytoplankton.