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MMS ENVIRONMENTAL STUDIES PROGRAM: ONGOING STUDIES |
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MMS OCS Region: |
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Title: |
Modeling Waves and Currents Produced by Hurricanes Katrina and Rita (GM-06-x10) |
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Planning Area: |
Gulfwide |
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Total Cost: $550,000 |
Period of Performance: FY 2006-2008 |
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Conducting Organization: |
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MMS Contact: |
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Description: Background: The destructive forces of Hurricanes Katrina
and Rita had a marked effect on oil and gas production in the northern Measurements of currents, waves, and temperature beneath hurricanes are comparatively rare, and are generally due to the fortuitous prior deployment of moorings for other reasons in waters over which a hurricane eventually passes. Such moorings do not generally survive the storm, and present difficulties in data analyses due to effects of the storm such as mooring tilt. However, such moorings survived Hurricane Ivan in 2004. Surface waves are thought to have exceeded 130 feet in height near the eyewall of Hurricane Ivan, and waves as high as 91 feet were actually recorded at moorings that were fortuitously placed in the path of Ivan. These are the largest waves ever directly measured. Similar observations are not available
in the path of Hurricanes Katrina and Rita, which were category 5 hurricanes that
greatly affected OCS waters. Data from
the MMS sponsored Survey of Deepwater Currents in the The response of the ocean to hurricanes depends upon the speed at which the storm moves across the sea surface, but generally a train of lee waves is found moving along behind the storm. Also in the storm’s wake is a zone of upwelled water due to Ekman pumping associated with the hurricane. The ocean’s response to Hurricane Georges propagated downwards to at least 500 feet, resulting in a current jet (Dimarco, 2004). It is necessary to simulate three dimensional current structures in order to capture the complexity of circulation generated by the hurricanes. |
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Objectives: To assess the response of waves and currents
throughout the water column on the · a realistic simulation of circulation throughout the entire water column in Northern Gulf of Mexico continental slope and shelf regions, including the response of currents and waves to Hurricanes Katrina and Rita; · determination of the length of time for which substantial ocean response to these hurricane persisted; and · determination of the area or areas of greatest wave height and current speed |
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Methods: Methods are anticipated to include the
following tasks: · compile, quality-check, and analyze available meteorological and physical oceanographic data including satellite data and data needed for model forcing to include surface wind driving, river runoff, and surface heat flux; ·
conduct time-dependent
and three-dimensional simulations of currents and waves forced by hurricanes Katrina
and Rita using proven circulation and wave models, with realistic topography and
forcing, and with and without data assimilations; ·
ckill-assess the simulated results against observations focusing
on the slope and shelf of the northern ·
conduct sensitivity and
process studies in combination with observational analysis to better understand
the physics of current and wave responses to powerful storms; hence to explain
these responses for impact-assessments for Katrina and Rita as well as for future
hurricanes; ·
produce plots and numerical
data of (a) length of time for which substantial current and wave responses to
Katrina and Rita persisted, and (b) area or areas of greatest wave height and
current speed; and ·
summarize findings in a final report as well as in submissions to peer-reviewed
journals. |
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Products: Digital deliverables to be provided to MMS will include model output in the format specified, and a final report of findings. The final report must include a presentation of the impact of Hurricanes Katrina and Rita on OCS waves and currents, analyses, thorough discussion, and extensive, scholarly interpretation of findings. |
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Importance to MMS:
A simulation of the effect of Hurricanes
Katrina and Rita upon shelf, slope, and nearshore waves
and currents can contribute to the MMS mission by evaluating the maximum speeds
of hurricane driven currents and maximum height of hurricane driven waves in the
study area. This study will add to our
understanding of hurricane and tropical storm effects on circulation in the |
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Current Status: Draft final report received and in review. |
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Final Report Due: |
March 2008 |
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Publications: |
Yin, X.-Q., and L.-Y. Oey. 2007. Bred-ensemble ocean forecast of Loop Current
and eddies. Ocean Modeling 17(4):300-326. |
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Affiliated WWW Sites: |
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Revised date: |
March 2008 |
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ESPIS |
ESPIS
- All completed ESP Studies: |
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