Assessing Hurricane Assessing Hurricane Intensity Intensity

TEAM TIGERSTEAM TIGERSHeatherHeatherEleanorEleanorMatt Matt AristaArista

ElizabethElizabeth

This presentation funded by HalliburtonThis presentation funded by Halliburton

Is it all Hype?Is it all Hype?•Mean hurricane intensity Mean hurricane intensity has not increased in a has not increased in a statistically significant way statistically significant way over time over time

•Occurrence of category 5 Occurrence of category 5 hurricanes in the past 15 hurricanes in the past 15 years is due to many years is due to many factorsfactors

•Measurement of Measurement of hurricanes before 1940s hurricanes before 1940s unreliableunreliable

Average Category Rating

y = -0.0056x + 13.435

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Linear (average category)

XX22 value= .482627 value= .482627within p=.05 therefore the null hypothesis is not rejectedwithin p=.05 therefore the null hypothesis is not rejected

The linear regression shows a downward trend The linear regression shows a downward trend and chi-squared value also supports the null and chi-squared value also supports the null hypothesis which is that hypothesis which is that hurricane strength is hurricane strength is not increasingnot increasing

Hurricane Isabel storm front

Climate Models are not Climate Models are not reliable: reliable:

Los Ninos ExampleLos Ninos Example• La Nina and El Nino affect sea surface La Nina and El Nino affect sea surface

temperature and hurricanestemperature and hurricanes• La Nina increases hurricane severity by La Nina increases hurricane severity by

warming the Atlantic Oceanwarming the Atlantic Ocean• El Nino decreases hurricane severity since it El Nino decreases hurricane severity since it

cools the Atlantic Oceancools the Atlantic Ocean• But really the data doesn’t statistically support But really the data doesn’t statistically support

it!it!• In years with category 5s, such as 2005, there In years with category 5s, such as 2005, there

is not necessarily an influence from Los Ninosis not necessarily an influence from Los Ninos

El Nino and La NinaEl Nino and La Ninacorrelation value= -0.114789correlation value= -0.114789

Therefore there is no correlation to category 5sTherefore there is no correlation to category 5s

Cat 5s vs La Nina and El Nino events

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El Nino and La Nina Events

Future ResearchFuture Research

• Without a significant increase in Without a significant increase in mean hurricane intensity over time mean hurricane intensity over time it is impossible to show a it is impossible to show a consistent correlation with other consistent correlation with other factors, like SSTfactors, like SST

• Must measure changes in Must measure changes in atmospheric and oceanic conditionsatmospheric and oceanic conditions

Historical frequency of high Historical frequency of high intensity hurricanesintensity hurricanes

Hurricane Fran

El FinEl Fin

• Our data shows that mean Our data shows that mean strength is not increasingstrength is not increasing

• Represents uncertainty in climate Represents uncertainty in climate and hurricane data manipulationand hurricane data manipulation

• Trends in hurricane intensity needs Trends in hurricane intensity needs to be measured for longer to be measured for longer

• Not enough dataNot enough data

Questions?GRRRREAT!