Earth  ID: 20029

Ocean Circulation Conveyor Belt Helps Balance Climate

As part of the ocean conveyor belt, warm water from the tropical Atlantic moves poleward near the surface where it gives up some of its heat to the atmosphere. This process partially moderates the cold temperatures at higher latitudes. As the warm water gives up its heat it becomes more dense and sinks. This circulation loop is closed as the cooled water makes its way slowly back toward the tropics at lower depths in the ocean.
If the poles warm, it is possible that melt water from glaciers and the polar ice cap can shut off this circulation and interrupt this circulation system. The melt water is fresher and hence less dense than the ocean water it melts into, and thus the melt water will tend to accumulate near the surface. This layer of fresh water acts as an insulating barrier between the atmosphere and the normal ocean water. The water from the tropics can not release its heat to the atmosphere, and the circulation loop is interrupted. The mechanism has a positive feedback potential in that if the ocean circulation slows, then even less heat will make it to the higher latitudes re-enforcing an effect that will cool the climate at these higher latitudes.

Animation Credits

Susan Twardy (HTSI): Lead Animator
David Adamec (NASA/GSFC): Scientist
David Adamec (NASA/GSFC): Writer
Please give credit for this item to:
NASA/Goddard Space Flight Center Conceptual Image Lab

Short URL to share this page:

SVS >> Byrne
SVS >> Climate
SVS >> Global Warming
SVS >> Gonnelli
SVS >> Ice Age
GCMD >> Earth Science
GCMD >> Earth Science >> Oceans >> Ocean Circulation >> Ocean Currents
NASA Science >> Earth

GCMD keywords can be found on the Internet with the following citation: Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version