U.S. Department of the Interior Minerals Management Service Gulf of Mexico OCS Region

MMS Releases Landmark Study that Assembles Historical Physical
Oceanography Data of Gulf of Mexico

A major synthesis of historical physical oceanographic data from the deep waters of the Gulf of Mexico has just been completed by Texas A&M University and the University of Colorado for the Minerals Management Service (MMS).  Titled Reanalysis and Synthesis of Physical Oceanography Historical Data, the study focuses on waters deeper than 200 meters across the northern Gulf, and from the surface to the seafloor.  The area is of interest to the MMS because of increased exploration for oil and gas along the continental slope and rise of the Gulf.  This study lays the groundwork for further research into the movement of water at all depths.

An understanding of the movement of water, such as tides and currents, is integral to the understanding of the marine environment and the focus of physical oceanographic studies.  This data synthesis includes much of what has been learned about water circulation in the Gulf of Mexico over the past fifty years and identifies what is still not understood.  All available data from governmental agencies, academic institutions, private organizations, and Mexican institutions were collected and compiled into a single database, which is available on three CD’s as part of the report.  The data were analyzed and the principal physical processes at work in deepwater were identified and prioritized according to the need for additional data.  The contractors identified criteria and constraints for designing future studies both in the field and in computer modeling.

The synthesized data paint an interesting picture of water movement in the Gulf of Mexico.  The major current in the Gulf is the Loop Current, which enters through the Yucatan Channel between Mexico and Cuba and exits through the Florida Straits.  The Loop Current is quite strong and is readily visible from satellite imagery as a stream of warmer water “looping” in the Eastern Gulf. Circular eddies of water break off from the Loop Current and transport water across the Gulf to the west.  These eddies can create short-term, high velocity currents at the surface as they pass by.  Surface currents are strongly affected by prevailing winds and storm events, such as hurricanes.

It was once thought that water movement below the surface decreased with increasing depth, and that very near the bottom, little to no water movement occurred.  This belief is no longer accepted and observations from the historical data indicate that there are some significant currents near the bottom.  The forces that create these currents are still not understood; in fact, it is only recently that these currents have been recognized.  These currents have left evidence; large furrows that cannot be explained by geologic events are present along the seafloor in the Eastern Gulf.

The information gathered for this report involved the cooperation of government agencies, universities, and the oil industry.  The data, some of which was not previously available to the public, were used to develop the picture of the Gulf of Mexico given in the report.  The data will be used by oil companies for designing structures that can withstand stronger currents at the bottom.  Scientists will use the data to understand the transport of plankton, larvae, and chemicals in the Gulf.

The synthesis of the physical oceanographic data has increased the understanding of the way water moves in the Gulf, but it also opens the door to more questions.  Suggestions for additional research include collecting more current data from moored data collectors on the northern slope and the use of data collectors that move with the water.  Oil and gas platforms could also be outfitted with instruments to measure currents.

A review panel of three independent experts gave this report excellent marks.  Among their comments was “Possibly the best report produced by the MMS studies program.”  This work is mandatory reading for anyone interested in learning about the deepwater physical oceanography of the Gulf of Mexico.  It is part of an ongoing MMS physical oceanography studies program that has invested over $50 million in research.

Reanalysis and Synthesis of Physical Oceanography Historical Data (OCS Study MMS 2001-064) and its three compact discs are available at a cost of $30 from the Public Information Office (MS 5034) at the following address:

U.S. Department of the Interior
Minerals Management Service
Gulf of Mexico OCS Region
Public Information Office (MS 5034)
1201 Elmwood Park Boulevard.
New Orleans, Louisiana 70123-2394
Telephone: 1-800-200-GULF; local 736-2519.

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