Flood Evacuation Function

Overview

Rating: 4

Limitation: The default threshold of 1 meter was selected based on consensus, not hard evidence.

Title: Need evacuation

Unique Identifier: Flood Evacuation Function

Permissible Hazard Input: A hazard raster layer where each cell represents flood depth (in meters).

Author: AIFDR

Actions: Provide details about how many people would likely need to be evacuated, where they are located and what resources would be required to support them.

Synopsis: To assess the impacts of (flood or tsunami) inundation on population.

Permissible Exposure Input: An exposure raster layer where each cell represent population count.

Details

The population subject to inundation exceeding a threshold (default 1m) is calculated and returned as a raster layer.In addition the total number and the required needs in terms of the BNPB (Perka 7) are reported. The threshold can be changed and even contain multiple numbers in which case evacuation and needs are calculated using the largest number with population breakdowns provided for the smaller numbers. The population raster is resampled to the resolution of the hazard raster and is rescaled so that the resampled population counts reflect estimates of population count per resampled cell. The resulting impact layer has the same resolution and reflects population count per cell which are affected by inundation.