Physical Oceanography

New Data on Deep Sea Turbulence Shed Light on Vertical Mixing

December 1, 1996

The global thermohaline circulation is basically a wholesale vertical overturning of the sea, driven by heating and cooling, precipitation and evaporation.

Labrador Sea Water Carries Northern Climate Signal South

Changes in wind strength, humidity, and temperature over the ocean affect rates of evaporation, precipitation, and heat transfer between ocean and air. Long-term atmospheric climate change signals are imprinted onto the sea surface layer, a thin skin atop an enormous reservoirA? and subsequently communicated to the deeper water masses. Labrador Sea Water is a subpolar water mass shaped by air-sea exchanges in the North Atlantic. It is a major contributor to the deep water of the Atlantic, and changes of conditions in its formation area can be read several years later at mid-depths in the subtropics. Mapping these changes through time is helping us to understand the causes of significant warming and cooling patterns we have observed at these depths in the North Atlantic and links the subtropical deep signals back to the subpolar sea surface conditions.

North Atlantic’s Transformation Pipeline Chills and Redistributes Subtropical Water

Warm and salty waters from the upper part of the South Atlantic flow northward across the equator and then progress through the tropical and subtropical North Atlantic to reach high latitudes. Beginning with the intense northward flow of the Gulf Stream off the East Coast of the United States, these waters are exposed to vigorous cooling, liberating considerable oceanic heat to the atmosphere. This is the first stage of “warm water transformation within the North Atlantic, a process that culminates in the high latitude production of cold and fresh waters that return to the South Atlantic in deep reaching currents beneath the warm waters of the subtropics and tropics.

If Rain Falls on the OceanDoes It Make a Sound?

As with similar questions about a tree in the forest or a grain of sand on the beach, it may be hard to imagine that a few inches of rain matters to the deep ocean.

Computer Modelers Stimulate Real and Potential Climate, Work Toward Prediction

Although weather forecasting is accepted by the public as part of daily life, oceanic forecasting is not yet so advanced. There are, however, successful examples of oceanic forecasting—one is the newly developed skill to predict El Nino/Southern Oscillation (ENSO) events, largely due to improvements in ocean modeling.

Oceans & Climate

The past decade has brought rapid scientific progress in understanding the role of the ocean in climate and climate change. The ocean is involved in the climate system primarily because it stores heat, water, and carbon dioxide, moves them around on the earth, and exchanges these and other elements with the atmosphere.

The Bermuda Station SA Long-Running Oceanographic Show

A time series of hydrographic measurements was initiated at Bermuda in 1954 and continues to the present. It began under the banner of the International Geophysical Year (1957-1958) with the scientific support of Henry Stommel of the Woods Hole Oceanographic Institution and William Sutcliffe, director of the Bermuda Biological Station (BBS). The scientists and personnel of the originating institutions have been the most active participants over the years, but the data have been widely used by the international oceanographic community. While other long time series of measurements in the North Atlantic began in association with weather ships, only the Bermuda measurements have a strong oceanographic focus.