Friday, 7 October 2011

Task 1 - Al Gore documentary


The North Atlantic Ocean Current – The Great Ocean Conveyor Belt

The north Atlantic ocean current starts with cold salty water at the surface of the north Atlantic which then sinks to the bottom of the sea, as it is so dense. This runs down south to Antarctica and to the east which takes it to the Pacific ocean where the cold water starts to rise from being heated and therefore being made less dense. As the water is heated it evaporates into the atmosphere and the sea becomes more salty which will eventually sink back down over in the west of the Atlantic.

This is the driving force that affects the weather. As the flow goes back east as warmer water, it heats the surrounding air currents from the gulf stream which is how Europe is warmed. The heat in the atmosphere means more moisture to be absorbed to be transported to be rain. After all the heat is realised into the atmosphere the water is cold and filled with salt that lets it sink back to the bottom of the sea.

It is also a transport system to take heat to the poles which limits the amount of ice that can build. It also carries rain over land.

It takes a 1000 years for the conveyor to complete its cycle.


What affects this cycle?

The balance of fresh and salt water in the ocean can change the momentum of the conveyor. If more fresh water is added to the current it would become less dense from diluting the amount of salt to water, and would not sink to the bottom of the ocean with enough energy to keep the current flowing along the bottom of the sea. Eventually the conveyer would stop.

This fresh water comes from the melting ice surrounding the sea. The ice melts because the atmospheres temperature rises from heat absorption and heats the water a degree or two around the ice and speeds up the pace of the ices melting with the addition of sun rays.
Some of the bigger masses of ice (Greenland) could contribute considerably to the sea level if melted off of the land. This could rise the level enough to be a threat to low lying land areas, and in this we would loose some landmass to the sea.


What affects the changes in the sea has?

Plant life in the sea is not getting enough nutrients. This can be seen from a study of plankton that glow more fiercely red from the lack of icon they are getting.
[1]

The bleaching of coral reefs from lack of pigment carrying organisms.

If the conveyor stopped, places that received warmth in that area from the water would become colder. If the poles become colder more ice could develop. This would become the trend of the rest of the land mass gaining freezing like temperatures from the lack of warming. 

This is not a new occurrence. The conveyor starts and stops with each new ice age. Today human race has possible sped up this proses by add our technological advancements into the mix.
 

No comments:

Post a Comment