Analyses of water and dredged material from selected southern Louisiana waterways and selected areas in the Gulf of Mexico, 1976-78

AbstractHurricane Gustav (2008) made landfall in southern Louisiana on 1 September 2008 with its eye never closer than 75 km to New Orleans, but its waves and storm surge threatened to flood the city. Easterly tropical-storm-strength winds impacted the region east of the Mississippi River for 12–15 h, allowing for early surge to develop up to 3.5 m there and enter the river and the city’s navigation canals. During landfall, winds shifted from easterly to southerly, resulting in late surge development and propagation over more than 70 km of marshes on the river’s west bank, over more than 40 km of Caernarvon marsh on the east bank, and into Lake Pontchartrain to the north. Wind waves with estimated significant heights of 15 m developed in the deep Gulf of Mexico but were reduced in size once they reached the continental shelf. The barrier islands further dissipated the waves, and locally generated seas existed behind these effective breaking zones.The hardening and innovative deployment of gauges since Hurricane Katrina (2005) resulted in a wealth of measured data for Gustav. A total of 39 wind wave time histories, 362 water level time histories, and 82 high water marks were available to describe the event. Computational models—including a structured-mesh deepwater wave model (WAM) and a nearshore steady-state wave (STWAVE) model, as well as an unstructured-mesh “simulating waves nearshore” (SWAN) wave model and an advanced circulation (ADCIRC) model—resolve the region with unprecedented levels of detail, with an unstructured mesh spacing of 100–200 m in the wave-breaking zones and 20–50 m in the small-scale channels. Data-assimilated winds were applied using NOAA’s Hurricane Research Division Wind Analysis System (H*Wind) and Interactive Objective Kinematic Analysis (IOKA) procedures. Wave and surge computations from these models are validated comprehensively at the measurement locations ranging from the deep Gulf of Mexico and along the coast to the rivers and floodplains of southern Louisiana and are described and quantified within the context of the evolution of the storm.

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Now & Then: From Manager to Meteorologist From Heavenly Bodies to Barometers

Mathematics Teaching in the Middle School ◽

10.5951/mtms.1.2.0123 ◽

1994 ◽

Vol 1 (2) ◽

pp. 123-129

Author(s):

Sue Barnes ◽

Karen Dee Michalowicz ◽

Melanie A. Womack

Keyword(s):

Gulf Of Mexico ◽

Late Summer ◽

Severe Weather ◽

Television Station ◽

Large Town ◽

Southern Louisiana

Now… Shreveport is a large town in Northwest Louisiana. A state that is classified as a severe-weather area. Northern Louisiana is often hit by thunderstorms and tornadoes. Southern Louisiana, on the Gulf of Mexico, is susceptible to hurricanes during late summer. When the manager of television station KSLA in Shreveport began looking for a person to fill the weather-news slot a few years ago, he did not want someone who could just point to a weather map. He wanted a good meteorologist. In regions that have invariant weather, those people who give the weather are usually actors or actresses who read the predictions prepared by someone else. The study of weather, however, is called meteorology, and a professional meteorologist is someone who has a degree in weather study. Even in area with severeweather conditions, some television stations do not hire a professional meteorologist but hire a broadcast meteorologist instead. A broadcast meteorologist is a journalist who has taken general courses in meteorology while studying for a communications or journalism degree.

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