Hurricane Katrina Damage Analysis Alex Stern and William Tran

Hurricane Katrina Damage Analysis

Alex Stern and William Tran

Overview

Assess the flood extent and impact created by Hurricane Katrina in New Orleans

Examining Orleans Parish

Duke University

Initial Steps

Collect Data Landsat 5 images from August 25th,

2005 and September 7th, 2005 Extract to Orleans Parish using Arc

Map, Parish shapefile

Classification

Accuracy Assessment 2005 NAIP 2m orthophoto mosaicClass Reference Classified Number Producers Users Name Totals Totals Correct Accuracy Accuracy

Class 0 38 54 38 --- --- Urban 16 25 10 62.50% 40.00% Vegetation 38 20 20 52.63% 100.00% Wetlands 15 24 11 73.33% 45.83% Flooded 1 0 0 --- --- Water 42 27 27 64.29% 100.00%

Overall Classification Accuracy = 70.67%

Overall Kappa Statistics = 0.6291

 Class Name Kappa Class 0 0.6032 Urban 0.3284 Vegetation 1.0000 Wetlands 0.3981 Flooded 0.0000 Water 1.0000

*No accuracy assessment performed on post-storm image

Rough Estimate

Tabulated Data

Flooded Urban

Urban to Vegetation

Water to Wetlands

Tabulated Data

Change Detection 37 sq miles of flooded urban 54 sq miles of flooded land Increase of water and vegetation Urban class lost 56 sq. miles

Evaluated over total land area:○ 134,585 persons displaced, 16,697 housing units

damagedEvaluated over urban land area:○ 281,332 persons displaced, 34,916 housing units

damaged

Loss of wetlands, errors4 sq miles of wetlands changed to urban

Problems and Limitations Inaccuracy of classifications Inaccuracy of census data

interpretation and analysis Limitation of area analyzed Technical Errors

○ ArcMap conversions○ Differences in shapefiles○ Multiple extractions

Real World Application

FEMA Military Insurance rates

Questions?

NASA/Jeff Schmaltz, MODIS