Joseph Fitzwater, Senior Analyzing Hurricane Intensity with a New Classification for the 21 st Century

Introduction Hurricane Katrina is the costliest natural disaster in US history. Its classification on the current hurricane system in use did not justify this extreme storm.

The Saffir-Simpson Scale The current scale in use for classifying hurricanes Created in 1971 by Herbert Saffir and Robert Simpson Based solely on wind speed

Purpose of Capstone Create a modern classification for hurricanes before storms make landfall Base this classification on more than just winds More information on a hurricane used in a classification yields a more accurate product to share to citizens

Methodology 1) Determine availability of data 2) Find hurricane parameters where data is available, and the parameter is applicable to strength 3) Create a ranking system for each parameter based on the past twenty-five hurricanes 4) Use each parameter ranking method to create a final point product, which can be used to compare with other hurricanes

1) Determine Availability of Data Data available from the NHC (National Hurricane Center) Only some data is available for older hurricanes

2) Find Hurricane Parameters Where Data is Available, and the Parameter is Applicable to Strength Parameters chosen based on availability of data in step 1 Parameters include: 1 minute sustained wind speed (As used by Saffir-Simpson scale, knots) Tropical storm force wind radii (knots) Hurricane storm force wind radii (knots) Pressure (mbar) Velocity (knots)

Maximum One Minute Sustained Wind Speeds A major indicator in determining strength of storm Found near the eye wall of a hurricane

Wind Force Radii The amount of distance from the eye (center) of a hurricane where a specific wind speed is measured. Hurricane force wind radii: Distance from the center where hurricane force wind speed is measured (65 knots). Tropical storm force wind radii: Distance from the center where tropical storm force wind speed is measured (35 knots).

Pressure Generally parallels strength with maximum one-minute sustained winds of a hurricane. Measure of the barometric pressure of the center of the storm.

Velocity Hurricanes generally produce similar rainfall rates Huge indicator of flooding.

3) Create a ranking system for each parameter based on the past twenty-five hurricanes The last twenty-five hurricanes to make landfall in the United States were analyzed. These twenty-five hurricanes were ranked in groups of five based on each parameter These equal intervals produced their own natural categories of rank to be used in the classification method.

3) Create a ranking system for each parameter based on the past twenty-five hurricanes

Final Scoring Method for Each Hurricane Parameter

Saffir-Simpson Hurricane Rank

Modern Hurricane Classification Rank

Application: Hurricane Katrina This methodology of classifying hurricanes can easily be used for real time. Hurricane Katrina’s path and categorization rank using the modern classification system.

Conclusions: Categorical Change Many hurricanes changed their category under the new classification method.

Conclusions 1) The size of a hurricane’s impact has a significant impact on this project’s categorization system. 2) Wind speed still bears a large weight in determining classification, but the introduction of additional parameters lessens its impact. 3) Velocity has a significant role in this classification, since flooding is a common bi-product of hurricanes.

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