Impacts comparison by using different hydraulic models on the 2011 flood in Thailand

The 2011 flood event in Thailand was devastating both in terms of lives and economic losses. Following this event, the (re)insurance industry have deeply transformed its underwriting practices and used new modeling tools, both external and internal.

A loss is linked both to hazard and sites characteristics. As an insurer's exposure changes, losses for the same event can differ greatly from past observations. Therefore, hazard maps representing a past event can be used to estimate losses as of today.

Building an internal flood risk model requires to create a large set of spatial grids of flood depth. The water depth spatialisation, based on the water level of identified rivers, is a crucial part of the modeling and called the hydraulic modeling.

This poster will :

(i) the use of two hydraulic models to obtain a flood footprint: The software Super-Fast Inundation of CoastS (SFINCS) (Leijnse et al., 2021), a 2D open-source fast numerical model, and LISFLOOD-FP (Bates, 2004).

(ii) calculate insured losses on a fictive portfolio in Thailand using these two models with the same inputs.

(iii) describe and explain the discrepancies steming from (ii).