Global Warming's

Effect on Thermohaline Circulation

What is Thermohaline Circulation? And How Does it Work?

Thermohaline Circulation, often referred to as the ocean conveyor belt, refers to the process of the ocean currents movement around the globe. There are two factors that cause the water to move. The first reason that the ocean water moves is a result of wind. When ocean water is in a very hot area evaporation occurs. Although the water evaporates the salt does not therefore the water becomes more dense and sinks to the bottom of the ocean. This water then travels to Antarctica and overturns. Overturning means that the water then travels upwards into warmer areas and the cycle repeats.

Global Warming's Effect on Glaciers and How it Affects Thermohaline Circulation

As a result of the increasing temperatures the glaciers are melting. As a result of the melting glaciers there is an increase in freshwater in the ocean. The increase in freshwater causes the Thermohaline Circulation to slow down. The slowing occurs because, as the picture below on the left shows, the ocean water has less salinity.


Could Global Warming Cause an Ice Age? Has it Happened Before?

Climatologists warn that global warming will slow the Thermohaline Circulation 10-50% in the next 100 years. If even one part of the Thermohaline Circulation is disrupted then the whole cycle stops. If this were to occur a rapid cooling would take place. This cooling would be very severe, Antarctica would experience winters twice as cold as any winter on record. If the Thermohaline Circulation stops and nothing is done about it an ice age could occur and mass extinction would take place. A rapid cooling due to a slowing in Thermohaline Circulation took place about 12,800 years ago and last for 1,300 years.


How Does the Stop of Thermohaline Circulation Affects Food Webs in the Coral Reefs?

If the Thermohaline Circulation were to stop then the coral reefs would die. They would die because 95% of their food is obtained from zooxanthellae, which would die. Approximately one third of all fish species live in coral reefs. Therefore if the Thermohaline Circulation was to stop then one third of fish species would not have a habitat.


How to Stop the Slowing of Thermohaline Circulation

The slowing of Thermohaline Circulation is occurring as a result of more fresh water then normal in the worlds oceans. More fresh water is being emitted into the oceans because of melting glaciers, due to global warming. Greenhouse gases being emitted into the air is causing global warming to occur. In order to stop the slowing of Thermohaline Circulation global warming would need to be stopped. The greenhouse effect occurs when there is an unbalance of greenhouse gases in the atmosphere. Balance of greenhouse gases could be restored to the atmosphere if the burning of fossil fuels and the cutting down of trees would stop. This could happen through government regulation and human involvement. This can be achieved through Kyoto Protocol, a legal agreement in which countries reduce the amount of greenhouse gases emitted in the air annually. Although many industrialized nations have signed the Kyoto Protocol the United States has not. Although the Kyoto Protocol would have many positive effects there are also some downsides. For example it would be very costly for the United States to adopt the Kyoto Protocol and the Kyoto Protocol does not monitor the emissions of greenhouse gases for the less developed nations. I think that Kyoto Protocol is the best solution. However, I think there needs to be some changes. The Kyoto Protocol should be expanded to less developed countries as well as more developed countries in order to have the best possible affect.