Developing City-Wide Hurricane Impact Maps using Real-Life Data on Infrastructure, Vegetation and Weather

Abstract

Hurricanes affect thousands of people annually, with devastating consequences such as loss of life, vegetation and infrastructure. Vegetation losses such as downed trees and infrastructure disruptions such as toppled power lines often lead to roadway closures. These disruptions can be life threatening for the victims. Emergency officials, therefore, have been trying to find ways to alleviate such problems by identifying those locations that pose high risk in the aftermath of hurricanes. This paper proposes an integrated methodology that utilizes both Google Earth Engine (GEE) and geographical information systems (GIS). First, GEE is used to access Sentinel-2 satellite images and calculate the Normalized Difference Vegetation Index (NDVI) to investigate the vegetation change as a result of Hurricane Michael in the City of Tallahassee. Second, through the use of ArcGIS, data on wind speed, debris, roadway density and demographics are incorporated into the methodology in addition to the NDVI indices to assess the overall impact of the hurricane. As a result, city-wide hurricane impact maps are created using weighted indices created based on all these data sets. Findings indicate that the northeast side of the city was the worst affected because of the hurricane. This is a region where more seniors live, and such disruptions can lead to dramatic consequences because of the fragility of these seniors. Officials can pinpoint the identified critical locations for future improvements such as roadway geometry modification and landscaping justification.

Post-Hurricane Vegetative Debris Assessment Using Spectral Indices Derived from Satellite Imagery

“…Inclusion of this dataset was inspired by the previous hurricane damage assessment studies conducted in the same study area. For example, it was found out that geographical units with a more elderly population and low-income households were likely to be located in areas with a high risk of roadway closures and power outages after Hurricane Hermine and Michael ( 26 – 28 ).…”

“…Apart from the storm surge-related and environmental characteristics, several studies paid attention to the impact of hurricane-related and debris-based disruptions on different socioeconomic groups while considering vulnerability and resilience of those groups ( 26–28 , 35–38 ). For example, a report from Congressional Research Services states that the African-American population with low income suffered the most from Hurricane Katrina-induced debris ( 36 ).…”

“…(RQ3) Given that power outages and roadway closures from Hurricanes Hermine and Michael affected regions differently based on the socioeconomic differences in factors such as age, income, and the ethnicity ( 26–28 , 35–38 ), is there any socioeconomic indicator related to post-hurricane vegetation debris? Can this information identify higher-risk regions in terms of debris and help debris removal operations for certain BGs?…”

“…Spectral indices can provide accurate estimations on land characteristics such as vegetation health ( 23 ), developed land ( 24 ), or water surfaces ( 25 ) to replace field data collection in debris assessments. Additionally, recent damage assessments studies from North Florida indicate that hurricane-induced infrastructure disruptions such as roadway closures and power outages are more likely to occur in low-income and vulnerable population areas ( 26 – 28 ). Thus, this study proposes a data fusion framework combining spectral and vector datasets to evaluate the vegetative debris collected in Tallahassee, FL after Hurricane Michael in 2018.…”