UK-based flood risk modeller Fathom claims to have developed a new flood model that is set to fundamentally change the understanding of the risk by providing an unparalleled view of flood hazard across mainland US.
Fathom-USv2 is a national-scale model adapted to account for climate change rather than relying solely on historic records.
It has been developed to provide a current climate change scenario for 2020 as well as a 2050 future climate state and uses synthetic hurricane data to forecast changing hurricane behaviour.
With the Atlantic 2020 hurricane season commencing this month and expected to be above average in severity due to a forecast of neutral-to-weak La Niña conditions and high sea surface temperatures, Fathom notes that accurate flood risk analysis is vital in avoiding the devastating losses seen from previous storms such as Hurricane Harvey in 2017.
“With the launch of Fathom-USv2, we are delivering a step-change in flood risk for the US insurance industry. We are seeing evidence that climate change is already affecting global weather patterns, including hurricane intensity, and yet until now there has been no systematic attempt to account for it when modelling flood risk at the national scale,” said Dr. Christopher Sampson, co-founder of Fathom.
“Coupled with the limited coverage of existing FEMA flood maps, it is no surprise that flood risk exposure has been significantly understated to date. The complex data analytics and blanket coverage of Fathom-USv2 will now enable not only insurers, but also individual members of the public, to confidently forecast flood risk and put in place the appropriate mitigation measures.”
Fathom-USv2 was developed in collaboration with more than 70 experts from world-leading research institutions. The inland flood model uses the latest terrain and river network data, and explicitly covers every watercourse regardless of size.
Fathom-USv2 also quantifies coastal flood risk due to storm surge and extreme high tides and covers the entire east and west US coastlines.
Coastal areas may flood from extreme water levels resulting from high tides alone or the additional uplift caused by storm surge.
As the first national-scale model to account for climate change, Fathom-USv2 uses data from more than 50,000 synthetic hurricanes from the Massachusetts Institute of Technology to reflect increasing storm severity and their impact on both inland and coastal flooding.