The South West Atlantic is a very productive part of the global ocean. This MODIS image from the Terra satellite shows the east coast of Argentina and the Falkland Islands. The ocean between is filled with swirls of lighter colour which are a plankton bloom along the continental shelf of South America.
The high plankton productivity means that there is food for the higher predators - and this region is famed as an extraordinarily rich squid fishing ground. In 2014 the fishery apparently took over 1/4 million tons of the squid Illex argentinus.
In just 2 and a half minutes the voice-over explains what the Gulf Stream is, how much heat it carries (“every day it gives more heat than the world’s coal supply in 2 years“), and what would be the impact on some regional climates if its pathway was deliberately moved by geoengineering.