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Challengingthe Odds ofHurricaneDamage DataCollectionA Detailed Account from a First ResponderDr. Beverley AdamsRemote Sensing Technical DirectorLondon, EnglandDr. J. Arn WombleWind EngineerLong Beach, Calif.ImageCat, Inc.www.imagecatinc.comShubharoop Ghosh of ImageCat,Inc. and Carol J. Friedland ofthe Louisiana State UniversityHurricane Center also contributedto this article.See several additionalresponders’ stories in relatedarticle on page 32.ven though it may be the most well-knownhurricane of recent history, Hurricane Katrina,which struck the U.S. Gulf Coast stateson Aug. 29, 2005, was only the third mostpowerful windstorm of the 2005 season. Itwas not Katrina’s power, but her storm surgethat caused catastrophic damage along thecoastlines of Louisiana, Mississippi and Alabama.After the levees separating Lake Pontchartrainfrom New Orleans were breachedby the surge, about 80 percent of the city wasleft flooded. All told, Hurricane Katrina wasresponsible for an estimated $75 billion indamages, and the deaths of 1,418 people.Countless relief organizations madethemselves available to help the impacted regionsusing an arsenal of advanced technologies.We at ImageCat have spent the pastfew years refining our portable VIEWS ®(Visualizing Impacts of Earthquakes withSatellites) reconnaissance and visualizationsystem to map and assess damage in theaftermath of major natural disasters suchas Hurricane Charley, the Bam Iran earthquakeand the Southeast Asian tsunami.By the time Hurricane Katrina hit, wecould draw upon our collective experienceand were well equipped to respond.We quickly realized that Katrina’s uniquecombination of certain circumstances createddramatic — but not insurmountable— challenges for mapping and assessingdamage. See Figure 1.Hurricane Katrina:Unique Among StormsIn terms of windspeed, Hurricane Katrinawas not a major event. Prior to reaching land,Katrina’s windspeed measurements indicatedthat maximum sustained winds exceeded170 miles per hour, making it a Category 5storm. But the storm weakened significantlyin the 18 hours preceding landfall, and thestorm had decreased to a Category 3, basedon sustained windspeeds. However, tremendousstorm-surge capabilities persisted fromthe storm’s prior Category 5 status.Hurricane Katrina’s landfall near theLouisiana-Mississippi border placed theMississippi Coast in the classically vulnerableright side of the hurricane. Windspeedsin New Orleans likely did not exceed Category1 or 2 levels. While the west side of thehurricane did experience lower windspeedscompared to the east, the particular locationof Lake Pontchartrain resulted in waterbeing pushed towards New Orleans, stressingthe miles of levees constructed to holdback the lake and the network of canals.Coupled with the below-sea-level elevationof the city, this situation proved disastrousas floodwaters poured into New Orleans.As a historic event, Hurricane Katrinawas devastatingly record-breaking. Certainly,it was quickly acknowledged as the costliestU.S. hurricane on record, causing billions26 s u m m e r 2 0 0 6 w w w . i m a g i n g n o t e s . c o m