Estuaries and Coasts

, Volume 31, Issue 4, pp 704–718 | Cite as

Characteristics of Extreme Meteorological Forcing and Water Levels in Mobile Bay, Alabama

  • Haihong Zhao
  • Qin Chen


The paper presents comprehensive statistical analyses of winds and water levels in Mobile Bay, Alabama, based on long-term meteorological and tidal observations at several locations. A procedure has been developed to select the most probable parent distribution function from a list of candidate distributions. The theoretical functions that fit the data best enable us to predict the extreme values of winds and water levels at different return periods. We have demonstrated the importance of dividing the winds into hurricane and nonhurricane seasons and separating astronomical tides from weather-driven water level changes. The statistical analysis suggests that the wind speed averaged over 8 min at Dauphin Island, Alabama, at the 100-year return period would be 48.9 m/s, which is equivalent to a sustained 1-min wind of 205 km/h, a very strong category 3 hurricane on the Saffir-Simpson scale. The probability distribution models predict that the 100-year maximum water level would be 3.23 m above the mean lower low water (MLLW) level at the bay entrance and 3.41 m above the MLLW level near the head of the bay, respectively. Extremely low water levels important to navigation are also found. Application of the predicted extreme winds and surges is illustrated through the development of a storm wave atlas in the estuary. It is expected that the methodology and results presented in this paper will benefit the management and preservation of the ecosystems and habitats in Mobile Bay.


Shallow estuary Physical forcing Extreme water levels Extreme winds Storm surge Wind waves Astronomical tides Statistical analysis 



The study was supported in part by the National Science Foundation (NSF Grant No. 0652859), the US Fish and Wildlife Service (FWS), and the Alabama Center for Estuarine Studies (ACES). Discussion with Dr. Bin Wang was helpful. Any opinions, findings, and conclusions or recommendations expressed in this paper are those of the authors and do not necessarily reflect the views of the NSF, FWS, or ACES.

Supplementary material

12237_2008_9062_MOESM1_ESM.pdf (834 kb)
ESM (PDF 834 kb)


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Copyright information

© Coastal and Estuarine Research Federation 2008

Authors and Affiliations

  1. 1.Department of Civil and Environmental EngineeringLouisiana State UniversityBaton RougeUSA

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