Formation

Around the world there are six large ocean gyres. The biggest ocean gyre stretches across the North Pacific Ocean and is responsible for the great Pacific garbage patch. The gyre is caused due to warm water from the South Pacific colliding with cooler water from the North Pacific. The trash that is entering the ocean from the coastlines and ships is captured in the center of the North Pacific ocean from the gyres. The gyres form a spiral which moves around and around in a circle across the entire northern ocean. 

It takes many years for the garbage from the coastlines to reach the garbage patch. Sometimes the garbage origins from the center of a continent and is washed into the ocean through lakes and rivers. Often it takes up to seven years for the garbage to reach the garbage patch. However, 20% of the trash in the garbage patch is caused from ships driving through the Pacific. Often fishing nets, plastic containers and goods that are transported on ships fall into the ocean and become part of Pacific garbage patch. A famous story of debris entering the ocean took place in 1992 when 28,000 rubber ducks fell from a container ship into the Pacific Ocean.

The diagrams below show the journey of trash from the coastlines of the continents to the garbage patch in the Pacific Ocean caused by the gyres.

The trash from the continents is entering the ocean through rivers, lakes or is swept away from the coasts. This takes about 6 months.

For the next two years the trash is traveling thousans of kilometers into the open ocean and is during this time always going with the current.

After four years the trash has gathered in the center and arround the currents. 

After six years the trash has reached its final destination where it will stay for many years caught inside the currents which keep it from returning back to land. This habit only changes in case of large storms, hurricanes or tsunamiens which drag the garbage with them towards the land.