Danish Nationwide Sea Level Rise Flooding Tool

The tool visualises the flooded area for a (user-) given sea-level rise, and is part of the national climate change adaptation portal available to government specialist, as well as citizens.

It is made possible by a computation performed by SCALGO on a very accurate 1.6 metre resolution raster terrain model for the entire country of Denmark. The detailed and thus massive model contains more than 20 billion cells.

The SCALGO technology for processing massive terrain data on normal desktop computers was essential for the computation behind the sea-level rise flooding tool. Using the SCALGO Hydrology software package the computation can be performed on the entire model of Denmark (without thinning or tiling) in approximately a day and a half on a normal desktop computer with 4GB of main memory. Apart from a module for the sea-level rise flood mapping, the package also includes modules for computing flow accumulation, watersheds, and bluespots (maximal depressions).

SCALGO also offers more advanced hydrological analysis computation services using in-house software, including the SCALGO Flash Flood Mapping product, which estimates the risk of flooding during extreme rain events. The mapping shows how much rain has to fall before any given cell of a detailed raster terrain is below water, and thus it also shows what part of the terrain is below water after a given amount of rain.