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Laboratory at Louisiana State University’s (LSU)Coastal Studies Institute in Baton Rouge, the betterestablished, proven technologies again proved theirmettle. What worked best for New Orleans were themultispectral modalities, although imagers had towait for the clouds to clear before they could gatherclean data. The radar data was very useful for mappingoil slicks.According to most accounts, companies and organizationsholding title to valuable stores of databanded together in a spirit of cooperation. RemembersWalker, “We got our radar imagery throughNOAA, and everybody that usually wants to selltheir imagery was willing to share it. I’m pretty surethat the big companies, once they see the light andthe scale of a disaster, they open up their libraries.”In pre- and post-storm analysis, some imaging technologieshave proven more useful than others. LiDAR,for example, relies on the physical distance of an airbornesensor to a reflective surface, and thus may beless helpful in situations where the modeler wants toquantify standing storm water on a volumetric basis sorational pump deployment decisions can be made.But new techniques are always coming to the fore.Jacqueline Mills, coordinator of LSU’s GIS Clearinghouse,said personnel working in the Lower NinthWard of New Orleans were grateful for the GPS-encodeddigital video system loaned by the NationalCenter for Geocomputation at the National Universityof Ireland. As window-mounted video camerasroll, the changing location of the vehicle can beHe isn’t exaggerating. On Aug. 31, NOAA postedmore than 350 aerial images of the decimated areabetween Bay St. Louis and Pascagoula, Miss. Thenext day it produced an additional 1,450 aerial images,including those picturing the mess Katrina hadmade of New Orleans. On Sept. 5, NOAA added another1,100 images to the repository.EarthData was called in to help strain variousdatasets in ways that could help rescuers delineatewhere houses and bridges had once stood. “Theytasked us to correct the mosaic and extract informationsuch as the debris line,” Demargne said.To deal with the exigencies of emergency logisticsplanning, the company generally favored colorinfrared imaging. “It’s a little bit easier to produce aland cover map,” Demargne explained. “We can calculatethe total amount of impervious surfaces andplug that into a hydrologic runoff model. What wedid is provide them with the basic information thatthey needed to run their models.”For Dr. Nan Walker, director of the EarthScanF i g u r e 2 Another satellite image showing Rita as itmade landfall. To the right is Florida, and to the left isMexico. (Courtesy of NOAA).traced onto a street network, greatly simplifying thechore of assessing damage, flood heights, and markingsfor search and rescue.“This type of geospatial technology could readilyreplace the manually intensive paper-only recordingapproaches of Red Cross damage assessment teams,”Mills wrote in a recent correspondence. “The obviousbenefit of this system is the speed and accuracyof data recording, and the dramatic reduction in humaneffort.”But flooding was by no means the all of it. When Katrinastruck, offshore oil platform valves and pipelinesacross a wide area in the Gulf region bent or snapped,fouling an estimated 534 square miles with crude oil,according to Skytruth (Shepherdstown, W.Va.), a nonprofitthat uses remote imaging to expand awareness ofenvironmental issues. Images Skytruth recorded on Sept.34 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
2 showed slicks over an area calculatedto host about 38,000 gallons of spilledoil. This estimate assumed that the slickswere just 1.1um (1/10,000th of a millimeter)thick, which is the lower limit for detectionon radar satellite images, so thisestimate is really a minimum.To get better estimates when mappingoil spills, fate/transport models(typically analytical solutions to simplifiedtransport equations) can beconceived to account for sea currents,temperature, turbidity and other factors.Skytruth founder John Amospoints to these exercises as good areasfor further research by specialists inthe thermal infrared and ultravioletspectrums.Skytruth images picturing lingeringoil several weeks after the stormsuggested that up to 100,000 gallonsof oil eventually were released fromleaking platforms and pipelines. Withlives and freshwater quality at stake,however, other emergency responsechores took precedence. Katrinatipped more than nine million gallonsof oil out of containers in and aroundNew Orleans, creating a hazard moreominous than that which wafted overthe ocean’s surface. “The Coast Guardwas quite rightly throwing its energyinto those spills,” Amos said.F i g u r e 3 This satellite image showsthe dry areas of New Orleans in pink andflooded regions in blue (Courtesy of SPOTImage).These spills amounted to little morethan grease spots when compared withthe 11,000 square miles of Alaska waterspolluted in 1989 as a result of the ExxonValdez accident. “Back in 1989 therewasn’t a whole lot of geospatial technologybeing used on the Exxon Valdez oilspill,” recalls Leslie Pearson, emergencyresponse program manager for the stateDepartment of Environmental Conservationin Anchorage. “We didn’t evenhave an Internet back then. It was a realpiecemeal effort.” Remote imaging andGIS have allowed quick responders tow w w . i m a g i n g n o t e s . c o ms u m m e r 2 0 0 635
Page 1 and 2: Summer 2006Vol. 21 No. 2E x c l u s
Page 3: See this image and the restof the w
Page 6: cover imageSummer 2006 / Vol. 21 /
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Page 17 and 18: Only a few months1after its launch
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Page 31 and 32: FIG 8Internet connection were able
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Page 39: Join the digital revolutionIntergra

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