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Articles 1 - 30 of 34

Full-Text Articles in Meteorology

The Effect Of Advection On The Three Dimensional Distribution Of Turbulent Kinetic Energy And Its Generation In Idealized Tropical Cyclone Simulations, Joshua B. Wadler, David S. Nolan, Jun A. Zhang, Lynn K. Shay, Joseph B. Olsen, Joseph J. Cione May 2023

The Effect Of Advection On The Three Dimensional Distribution Of Turbulent Kinetic Energy And Its Generation In Idealized Tropical Cyclone Simulations, Joshua B. Wadler, David S. Nolan, Jun A. Zhang, Lynn K. Shay, Joseph B. Olsen, Joseph J. Cione

Publications

The distribution of turbulent kinetic energy (TKE) and its budget terms is estimated in simulated tropical cyclones (TCs) of various intensities. Each simulated TC is subject to storm motion, wind shear, and oceanic coupling. Different storm intensities are achieved through different ocean profiles in the model initialization. For each oceanic profile, the atmospheric simulations are performed with and without TKE advection. In all simulations, the TKE is maximized at low levels (i.e., below 1 km) and ∼0.5 km radially inward of the azimuthal-mean radius of maximum wind speed at 1-km height. As in a previous study, the axisymmetric TKE decreases …


Climatological Analysis Of Tropical Cyclone Occurrence Dates And Landfall Characteristics In The North Atlantic And Eastern North Pacific, Nicholas Sava Grondin May 2023

Climatological Analysis Of Tropical Cyclone Occurrence Dates And Landfall Characteristics In The North Atlantic And Eastern North Pacific, Nicholas Sava Grondin

Doctoral Dissertations

Tropical cyclones (TCs) are significant hazards to coastal and inland regions across the globe, especially in North America. North America is affected by TCs from two basins, the North Atlantic (NATL) and eastern North Pacific (ENP), with the former being the predominate focus of past research. In this dissertation, I present three studies that directly compare TCs in the NATL and ENP by using the same methods for each basin in studying occurrence dates and intraseasonal variability, effects of environmental parameters on occurrence dates and seasonal forecasting, and the behavior of TCs during the final 36 hours before landfall in …


A Demonstration Of A Simple Methodology Of Flood Prediction For A Coastal City Under Threat Of Sea Level Rise: The Case Of Norfolk, Va, Usa, Tal Ezer Sep 2022

A Demonstration Of A Simple Methodology Of Flood Prediction For A Coastal City Under Threat Of Sea Level Rise: The Case Of Norfolk, Va, Usa, Tal Ezer

CCPO Publications

Many coastal cities around the world are at risk of increased flooding due to sea level rise (SLR), so here a simple flood prediction method is demonstrated for one city at risk, Norfolk, VA, on the U.S. East Coast. The probability of future flooding is estimated by extending observed hourly water level for 1927–2021 into hourly estimates until 2100. Unlike most other flood prediction methods, the approach here does not use any predetermined probability distribution function of extreme events, and instead a random sampling of past data represents tides and storm surges. The probability of flooding for 3 different flood …


Hydrometeorological Responses To Abrupt Land Surface Change Following Hurricane Michael, Shannon Alexis Nelson May 2021

Hydrometeorological Responses To Abrupt Land Surface Change Following Hurricane Michael, Shannon Alexis Nelson

LSU Master's Theses

While many of the destructive environmental conditions associated with tropical cyclones are well recognized, tropical cyclone-induced defoliation, a reduction in green leaves and mature vegetation, has been largely overlooked as a source of environmental stress following tropical cyclone passage. The land surface change associated with defoliation reduces evapotranspiration and shade, thus altering boundary layer moisture and energy fluxes that drive the local water cycle, for many months after tropical cyclone passage. Understanding the potential for any hydrometeorological impacts arising from such abrupt land surface change is important for guiding future post-hurricane preparedness and recovery planning in coastal communities.

This thesis …


Reveal Wind Loading Of Tornadoes And Hurricanes On Civil Structures Towards Hazard-Resistant Design, Ryan Honerkamp Jan 2021

Reveal Wind Loading Of Tornadoes And Hurricanes On Civil Structures Towards Hazard-Resistant Design, Ryan Honerkamp

Doctoral Dissertations

"Extreme winds impacting civil structures lead to death and destruction in all regions of the world. Specifically, tornadoes and hurricanes impact communities with severe devastation. On average, 1200 tornadoes occur in the United States every year. Tornadoes occur predominantly in the Central and Southeastern United States, accounting for an annual $1 billion in economic losses, 1500 injuries, and 90 deaths. The Joplin, MO Tornado in 2011 killed 161 people, injured more than 1000, destroyed more than 8000 structures, and caused $2.8 billion of property loss. Hurricanes occur predominantly on the United States East coast regions and along the coast of …


Climatology, Variability, And Return Periods Of Tropical Cyclone Strikes In The Northeastern And Central Pacific Basins, Nicholas S. Grondin Mar 2019

Climatology, Variability, And Return Periods Of Tropical Cyclone Strikes In The Northeastern And Central Pacific Basins, Nicholas S. Grondin

LSU Master's Theses

Tropical cyclones (TCs) are among the most destructive meteorological phenomena and impact the lives of people who reside along the coast. The American Pacific Coastline borders the second most active TC development region in the world, the northeastern Pacific (NE Pac) basin. This region, along with the Central Pacific (C Pac)-bordering Hawaii is home to a growing population and cities engaged in a variety of economic activities, most prominently agriculture, fishing, and tourism. This study analyzes fifty-two (1966-2017) years of NE Pac and C Pac TCs through applying track data from the National Hurricane Center’s HURDAT2 and a TC size …


Hurricane Model Development At Gfdl: A Collaborative Success Story From A Historical Perspective, Morris A. Bender, Timothy Marchok, Robert E. Tuleya, Isaac Ginis, Vijay Tallapragada, Stephen J. Lord Jan 2019

Hurricane Model Development At Gfdl: A Collaborative Success Story From A Historical Perspective, Morris A. Bender, Timothy Marchok, Robert E. Tuleya, Isaac Ginis, Vijay Tallapragada, Stephen J. Lord

CCPO Publications

The hurricane project at the National Oceanic and Atmospheric Administration (NOAA) Geophysical Fluid Dynamics Laboratory (GFDL) was established in 1970. By the mid-1970s pioneering research had led to the development of a new hurricane model. As the reputation of the model grew, GFDL was approached in 1986 by the director of the National Meteorological Center about establishing a collaboration between the two federal organizations to transition the model into an operational modeling system. After a multiyear effort by GFDL scientists to develop a system that could support rigorous requirements of operations, and multiyear testing had demonstrated its superior performance compared …


Dynamical And Precipitation Structures Of Poleward-Moving Tropical Cyclones In Eastern Canada, 1979-2005, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum Jun 2018

Dynamical And Precipitation Structures Of Poleward-Moving Tropical Cyclones In Eastern Canada, 1979-2005, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum

Shawn M. Milrad

Tropical cyclones in the western North Atlantic basin are a persistent threat to human interests along the east coast of North America. Occurring mainly during the late summer and early autumn, these storms often cause strong winds and extreme rainfall and can have a large impact on the weather of eastern Canada. From 1979 to 2005, 40 named (by the National Hurricane Center) tropical cyclones tracked over eastern Canada. Based on the time tendency of the low-level (850–700 hPa) vorticity, the storms are partitioned into two groups: ‘‘intensifying’’ and ‘‘decaying.’’ The 16 intensifying and 12 decaying cases are then analyzed …


Methodology To Analyze Tropical Cyclone Intensity From Microwave Imagery, Matthew W. Perkins Mar 2018

Methodology To Analyze Tropical Cyclone Intensity From Microwave Imagery, Matthew W. Perkins

Theses and Dissertations

Satellites with microwave remote sensing capabilities can be utilized to study atmospheric phenomena through high-level cloud cover (particularly cirrus), an advantage over visible and infrared bands, which only sense cloud tops. This unique capability makes microwave imagery ideal for studying the cloud structures of tropical cyclones (TCs) in detail, and relating these features to TC intensity. Techniques to estimate the intensity of TCs using infrared imagery, such as the Dvorak technique, have been used in TC forecasting for 40 years. However, due to the inherent temporal limitations of microwave imagery, no such similar technique exists for the microwave spectrum. This …


Evaluation And Predictability Of Observation-Based Surface Wind Asymmetric Structure In Tropical Cyclones, Bradley Klotz Mar 2017

Evaluation And Predictability Of Observation-Based Surface Wind Asymmetric Structure In Tropical Cyclones, Bradley Klotz

FIU Electronic Theses and Dissertations

Surface wind speeds are an important and revealing component of the structure of tropical cyclones (TCs). To understand the asymmetric structure of surface winds in TCs associated with differences in formation region, environmental wind shear, storm forward motion, and TC strength and intensification, a twelve year database of satellite scatterometer data are utilized to produce composite total wind speed and Fourier-derived, low wavenumber analyses. A quantified asymmetry is determined as a function of TC intensity and reveals the tropical storms are influenced by wind shear at all TC-centric radii but only for areas away from the radius of maximum wind …


Tropical Cyclone Intensification Under Moderate Vertical Wind Shear, Rosimar Rios-Berrios Jan 2017

Tropical Cyclone Intensification Under Moderate Vertical Wind Shear, Rosimar Rios-Berrios

Legacy Theses & Dissertations (2009 - 2024)

Deep-layer (200–850 hPa) vertical wind shear is generally an inhibiting factor for tropical cyclone intensification. Multiple studies—ranging from case studies to climatological analyses—have consistently shown that the chances of tropical cyclone intensification decrease with increasing vertical wind shear magnitude. However, tropical cyclones can intensify under moderate shear—the range of shear magnitudes that are neither too weak to have negligible influence on intensity nor too strong to completely halt intensification. Intensity, track, and precipitation forecasts of tropical cyclones under moderate shear can be highly uncertain; therefore, explaining how tropical cyclones evolve under seemingly unfavorable conditions is an important step towards improved …


Modeling The Impact Of Land Surface Feedbacks On Post Landfall Tropical Cyclones, Subashini Subramanian Dec 2016

Modeling The Impact Of Land Surface Feedbacks On Post Landfall Tropical Cyclones, Subashini Subramanian

Open Access Dissertations

The land surface is an important component of numerical models. The land surface models are modules that control energy partitioning, compute surface exchange coefficients and form the only physical boundary in a regional scale numerical model. Thus, an accurate representation of land surface is critical to compute surface fluxes, represent the boundary layer evolution and affect changes in weather systems. Land surface can affect landfalling tropical cyclones in two ways: (i) when the cyclone is offshore and land can influence cyclones by introducing dry (or moist) air that can weaken (or strengthen) the organized convective structure of cyclones, and (ii) …


Using Proxy Records To Document Gulf Of Mexico Tropical Cyclones From 1820-1915, Jordan V. Pino, Robert V. Rohli, Kristine L. Delong, Grant L. Harley, Jill C. Trepanier Nov 2016

Using Proxy Records To Document Gulf Of Mexico Tropical Cyclones From 1820-1915, Jordan V. Pino, Robert V. Rohli, Kristine L. Delong, Grant L. Harley, Jill C. Trepanier

Faculty Publications

Observations of pre-1950 tropical cyclones are sparse due to observational limitations; therefore, the hurricane database HURDAT2 (1851–present) maintained by the National Oceanic and Atmospheric Administration may be incomplete. Here we provide additional documentation for HURDAT2 from historical United States Army fort records (1820–1915) and other archived documents for 28 landfalling tropical cyclones, 20 of which are included in HURDAT2, along the northern Gulf of Mexico coast. One event that occurred in May 1863 is not currently documented in the HURDAT2 database but has been noted in other studies. We identify seven tropical cyclones that occurred before 1851, three of which …


Street-Level Inundation Modeling Of Hurricanes Matthew And Hermine And Emerging Flood Monitoring Methods In Hampton Roads, Jon Derek Loftis, H. V. Wang, D R. Forrest Nov 2016

Street-Level Inundation Modeling Of Hurricanes Matthew And Hermine And Emerging Flood Monitoring Methods In Hampton Roads, Jon Derek Loftis, H. V. Wang, D R. Forrest

Presentations

No abstract provided.


Seasonal Influences Upon And Long-Term Trends In The Length Of The Atlantic Hurricane Season, Juliana Marie Karloski May 2015

Seasonal Influences Upon And Long-Term Trends In The Length Of The Atlantic Hurricane Season, Juliana Marie Karloski

Theses and Dissertations

Atlantic tropical cyclone (TC) seasons vary yearly in length with some seasons significantly shorter or longer than normal. Kossin (2008) suggested that from 1980 to 2007, the Atlantic TC season increased in length; however, their study only considered a subset of the Atlantic basin south of 30°N and east of 75°W. It is uncertain whether this trend holds over the entire Atlantic basin or continues into the present. It is also unclear as to whether meaningful sub-seasonal variability in the environmental factors necessary for TC formation exists between early- and late-starting and -ending seasons.

Quantile regression is used to evaluate …


Quantifying The Sensitivity Of Maximum, Limiting, And Potential Tropical Cyclone Intensity To Sst: Observations Versus The Fsu/ Coaps Global Climate Model, Sarah Strazzo, James Elsner, Tim Larow Apr 2015

Quantifying The Sensitivity Of Maximum, Limiting, And Potential Tropical Cyclone Intensity To Sst: Observations Versus The Fsu/ Coaps Global Climate Model, Sarah Strazzo, James Elsner, Tim Larow

Publications

No abstract provided.


Towards Predicting Street-Level Inundation: Using Operational Forecast Modeling Techniques During 2011 Hurricane Irene, J. D. Loftis, H. V. Wang, D. R. Forrest Jan 2015

Towards Predicting Street-Level Inundation: Using Operational Forecast Modeling Techniques During 2011 Hurricane Irene, J. D. Loftis, H. V. Wang, D. R. Forrest

Presentations

Storm surge-induced coastal inundation poses numerous personal, commercial, industrial, and sociopolitical challenges for society. Flooding can be caused by the combination of storm surge and river-induced inland flooding in many locations throughout the coastal plain. The cross-disciplinary nature of the hydrodynamics involved (hydraulics, oceanography, and hydrology), coupled with the complexity of the atmospheric forcing, makes a numerical model the best approach for a comprehensive study of the dynamics of coastal inundation.

This study builds upon the lessons learned from forecast modeling experiences during 2011 Hurricane Irene in Tidewater Virginia, to ascertain the most effective way to approach predicting street-level inundation. …


Assessing Inland Hazards Associated With Hurricanes In The U.S. Atlantic Basin, Dereka Latrese Carroll Jul 2014

Assessing Inland Hazards Associated With Hurricanes In The U.S. Atlantic Basin, Dereka Latrese Carroll

Open Access Theses

The skill of tropical-cyclone (TC) track forecasts has steadily improved over the past decades, as has the understanding of TC risk in coastal regions. However, there is still much to be learned about the TC risk in inland regions, which is complicated by the presence of coastal evacuees, and includes hazards such as inland flash flooding and tornadoes. This was exemplified by Hurricane Ivan (2004), which spawned 118 tornadoes and produced significant rainfall amounts contributing to flooding inland. Ivan was responsible for 25 deaths in the U.S. and $18.8 billion (2004 USD) in damages. As part of a larger effort …


Probability Distributions And Threshold Selection For Monte Carlo–Type Tropical Cyclone Wind Speed Forecasts, Steven M. Lazarus, Michael E. Splitt, Sarah Collins, Denis N. Botambekov, William P. Roeder Apr 2014

Probability Distributions And Threshold Selection For Monte Carlo–Type Tropical Cyclone Wind Speed Forecasts, Steven M. Lazarus, Michael E. Splitt, Sarah Collins, Denis N. Botambekov, William P. Roeder

Aeronautics Faculty Publications

Probabilistic wind speed forecasts for tropical cyclones from Monte Carlo–type simulations are assessed within a theoretical framework for a simple unbiased Gaussian system that is based on feature size and location error that mimic tropical cyclone wind fields. Aspects of the wind speed probability data distribution, including maximumexpected probability and forecast skill, are assessed. Wind speed probability distributions are shown to be well approximated by a bounded power-law distribution when the feature size is smaller than the location error and tends toward a U-shaped distribution as the location error becomes small. Forecast skill (i.e., true and Heidke skill scores) is …


Keeney, Sean Carpenter (Sc 1259), Manuscripts & Folklife Archives Dec 2013

Keeney, Sean Carpenter (Sc 1259), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid only for Manuscripts Small Collection 1259. “My Experience of ‘Andrew,’” by Sean Keeney, Dade County, Florida, relating the effect on him and his family of Hurricane Andrew, which struck the area on 24 August 1992. Includes biographical data on Keeney.


Disher, John Lee, 1938-2019 (Sc 1183), Manuscripts & Folklife Archives Oct 2013

Disher, John Lee, 1938-2019 (Sc 1183), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid only for Manuscripts Small Collection 1183. Letter from John Lee Disher of Summerville, South Carolina, to his sister Nancy Disher Baird, Bowling Green, Kentucky, describing the aftermath of Hurricane Hugo.


Dynamical Downscaling Projections Of Twenty-First-Century Atlantic Hurricane Activity: Cmip3 And Cmip5 Model-Based Scenarios, Thomas R. Knutson, Joseph J. Sirutis, Gabriel A. Vecchi, Stephen Garner, Ming Zhao, Hyeong-Seog Kim, Morris Bender, Robert E. Tuleya, Isaac M. Held, Gabriele Villarini Sep 2013

Dynamical Downscaling Projections Of Twenty-First-Century Atlantic Hurricane Activity: Cmip3 And Cmip5 Model-Based Scenarios, Thomas R. Knutson, Joseph J. Sirutis, Gabriel A. Vecchi, Stephen Garner, Ming Zhao, Hyeong-Seog Kim, Morris Bender, Robert E. Tuleya, Isaac M. Held, Gabriele Villarini

CCPO Publications

Twenty-first-century projections of Atlantic climate change are downscaled to explore the robustness of potential changes in hurricane activity. Multimodel ensembles using the phase 3 of the Coupled Model Intercomparison Project (CMIP3)/Special Report on Emissions Scenarios A1B (SRES A1B; late-twenty-first century) and phase 5 of the Coupled Model Intercomparison Project (CMIP5)/representative concentration pathway 4.5 (RCP4.5; early- and late-twenty-first century) scenarios are examined. Ten individual CMIP3 models are downscaled to assess the spread of results among the CMIP3 (but not the CMIP5) models. Downscaling simulations are compared for 18-km grid regional and 50-km grid global models. Storm cases from the regional model …


Sensitivity Of Limiting Hurricane Intensity To Sst In The Atlantic From Observations And Gcms, James Elsner, Sarah Strazzo, Thomas H. Jagger, Timothy Larow, Ming Zhao Aug 2013

Sensitivity Of Limiting Hurricane Intensity To Sst In The Atlantic From Observations And Gcms, James Elsner, Sarah Strazzo, Thomas H. Jagger, Timothy Larow, Ming Zhao

Publications

No abstract provided.


Comparison And Validation Of Tropical Rainfall Measuring Mission (Trmm) Rainfall Algorithms In Tropical Cyclones, Joseph P. Zagrodnik Nov 2012

Comparison And Validation Of Tropical Rainfall Measuring Mission (Trmm) Rainfall Algorithms In Tropical Cyclones, Joseph P. Zagrodnik

FIU Electronic Theses and Dissertations

Tropical Rainfall Measuring Mission (TRMM) rainfall retrieval algorithms are evaluated in tropical cyclones (TCs). Differences between the Precipitation Radar (PR) and TRMM Microwave Imager (TMI) retrievals are found to be related to the storm region (inner core vs. rainbands) and the convective nature of the precipitation as measured by radar reflectivity and ice scattering signature. In landfalling TCs, the algorithms perform differently depending on whether the rainfall is located over ocean, land, or coastal surfaces. Various statistical techniques are applied to quantify these differences and identify the discrepancies in rainfall detection and intensity. Ground validation is accomplished by comparing the …


Sensitivity Of Limiting Hurricane Intensity To Ocean Warmth, James B. Elsner, Sarah Strazzo, Jill C. Trepanier, Thomas H. Jagger Sep 2012

Sensitivity Of Limiting Hurricane Intensity To Ocean Warmth, James B. Elsner, Sarah Strazzo, Jill C. Trepanier, Thomas H. Jagger

Publications

No abstract provided.


The Impact Of Oceanic Heat Content On The Rapid Intensification Of Atlantic Hurricanes, Kevin Law Aug 2012

The Impact Of Oceanic Heat Content On The Rapid Intensification Of Atlantic Hurricanes, Kevin Law

Kevin Law

With the increased infrastructure and amount of people living along the United States coastline, it is imperative to improve the accuracy of Atlantic hurricane intensity forecasts. Over the last 10 years, there have been many Atlantic hurricanes, including Hurricanes Katrina and Charley that surprised many forecasters with their rapid intensification and power. The rapid intensification of tropical cyclones is the most serious aspect, when it comes to forecasting. It is generally accepted that sufficient surface ocean temperatures (approximately 26°C) are needed to produce and sustain tropical cyclone formation. However, the sea-surface temperature (SST) has shown not to be critical in …


A Wrf Simulation Of The Asymmetric Rapid Intensification And Trough Interaction Of Tropical Storm Gabrielle (2001), Diana Elizabeth Thomas-Abernethy Jan 2012

A Wrf Simulation Of The Asymmetric Rapid Intensification And Trough Interaction Of Tropical Storm Gabrielle (2001), Diana Elizabeth Thomas-Abernethy

Legacy Theses & Dissertations (2009 - 2024)

Despite 13 ms-1 ambient wind shear, Tropical Storm (TS) Gabrielle underwent 22 hPa pressure falls within 3 hours prior to 0900 UTC 14 September. The rapid intensification of Gabrielle was atypical due to an upper-level trough approaching from the northwest. Additionally, a convective cell developed in the downshear left quadrant of the center, moved cyclonically and inward to the 17 km radius. During this time, The Tropical Rainfall Measurement Mission (TRMM) had one of its most intense 85 GHz scattering measurements ever (Molinari and Vollaro, 2010).


Dynamical And Precipitation Structures Of Poleward-Moving Tropical Cyclones In Eastern Canada, 1979-2005, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum Mar 2009

Dynamical And Precipitation Structures Of Poleward-Moving Tropical Cyclones In Eastern Canada, 1979-2005, Shawn M. Milrad, Eyad H. Atallah, John R. Gyakum

Publications

Tropical cyclones in the western North Atlantic basin are a persistent threat to human interests along the east coast of North America. Occurring mainly during the late summer and early autumn, these storms often cause strong winds and extreme rainfall and can have a large impact on the weather of eastern Canada. From 1979 to 2005, 40 named (by the National Hurricane Center) tropical cyclones tracked over eastern Canada. Based on the time tendency of the low-level (850–700 hPa) vorticity, the storms are partitioned into two groups: ‘‘intensifying’’ and ‘‘decaying.’’ The 16 intensifying and 12 decaying cases are then analyzed …


Numerical Simulations Of The Impacts Of The Saharan Air Layer On Atlantic Tropical Cyclone Development, Donglian Sun, K. M. Lau, Menas Kafatos, Z. Boybeyi, G. Leptoukh, C. Yang, Ruixin Yang Jan 2009

Numerical Simulations Of The Impacts Of The Saharan Air Layer On Atlantic Tropical Cyclone Development, Donglian Sun, K. M. Lau, Menas Kafatos, Z. Boybeyi, G. Leptoukh, C. Yang, Ruixin Yang

Mathematics, Physics, and Computer Science Faculty Articles and Research

In this study, the role of the Saharan air layer (SAL) is investigated in the development and intensification of tropical cyclones (TCs) via modifying environmental stability and moisture, using multisensor satellite data, long-term TC track and intensity records, dust data, and numerical simulations with a state-of-the-art Weather Research and Forecasting model (WRF). The long-term relationship between dust and Atlantic TC activity shows that dust aerosols are negatively associated with hurricane activity in the Atlantic basin, especially with the major hurricanes in the western Atlantic region. Numerical simulations with the WRF for specific cases during the NASA African Monsoon Multidisciplinary Analyses …


Hurricane Katrina, 2005 (Sc 1669), Manuscripts & Folklife Archives Jun 2008

Hurricane Katrina, 2005 (Sc 1669), Manuscripts & Folklife Archives

MSS Finding Aids

Finding aid only for Manuscripts Small Collection 1669. E-mails related to the personal and governmental response to Hurricane Katrina in Louisiana.