Tsunami evacuation time map for the island of O'ahu, Hawai'i, extreme tsunami evacuation zone and impaired walk speed
Description
The travel time map was generated using the Pedestrian Evacuation Analyst model from the USGS (https://geography.wr.usgs.gov/science/vulnerability/tools.html). The travel time analysis uses ESRI's Path Distance tool to find the shortest distance across a cost surface from any point in the hazard zone to a safe zone. This cost analysis considers the direction of movement and assigns a higher cost to steeper slopes, based on a table contained within the model. The analysis also adds in the energy costs of crossing different types of land cover, assuming that less energy is expended walking along a road than walking across a sandy beach. To produce the time map, the evacuation surface output from the model is grouped into 1-minute increments for easier visualization. The times in the attribute table represent the estimated time to travel on foot to the nearest safe zone at the speed designated in the map title. The file name indicates whether the map is of the standard or extreme evacuation zone used by the City and County of Honolulu and which travel speed was used in the modelling (impaired, slow, or fast walk).
These data support the following publication: Wood, N.J., Jones, J.L., Peters, J., and Richards, K., 2018, Pedestrian-evacuation modeling to reduce vehicle use for distant tsunami evacuations in Hawai'i: International Journal of Disaster Risk Reduction, v. 28, p. 271–283, https://doi.org/10.1016/j.ijdrr.2018.03.009.