What’s new in JBA’s latest UK Flood Model?

We’ve just released the latest version of our UK Flood Model – already the highest resolution UK probabilistic flood model available on the market, and now the model offering the most flexibility.

The latest release of the UK Flood Model is the third iteration in our continuous improvement plan. First released in 2015, the model was updated in 2018 to the highest resolution available (5m resolution), alongside the release of the first UK Climate Change Flood Model in the market.

Now, we’re combining JBA’s market-leading flood and climate science with a revolutionary new approach to catastrophe model development.

This provides unprecedented user customisation, better representation of risks for more intelligent reinsurance pricing and portfolio management, and the ability to truly own your view of risk for Solvency II and regulatory requirements.

So, what exactly is new in the UK Flood Model?

New technology

One of the major updates to the new UK Flood Model is the use of JBA’s revolutionary new modelling technology - it seamlessly integrates with Oasis LMF and the Oasis Financial Module and reporting modules to generate financial loss from flood.

This new technology redefines the traditional approach to catastrophe model development. Instead of building a model using pre-defined parameters, we can now bring a model into being at run time by intersecting hazard and exposure data at run time and only looking up the relevant hazard data for the user’s exposure.

This increased flexibility has multiple benefits:

• The ability to change almost every model parameter to truly own your view of risk and generate a tailored analysis to your specific requirements
• The ability to ask and investigate ‘what if?’ questions
• The ability to make full use of the high-resolution data rather than unnecessarily summarising it
• An understanding of exactly what goes into the model for more openness and transparency
• The ability to configure the model to more applications, from assessing the long-term view of risk to a residential portfolio to competitive reinsurance pricing

Modifiable elements include hazard data, such as choice of maps and event set, as well as location buffer, vulnerability functions, damage factor scales and more.

Our next blog will explore this customisable element in more depth.

New data

The latest UK Flood Model takes advantage of this new technology to incorporate multiple new data sources, from hazard to vulnerability data, for the most effective assessment of flood and financial loss. This includes:

• Updated hazard maps, using JBA’s 2020 5m UK Flood Maps for river, surface water and coastal flood. This incorporates a three-year update of our coastal mapping for England and Wales, updated DTM and lidar data, and improvements in sea level methods amongst others. These maps are complemented by new high return period maps for river and surface water flood, which now enable users to assess flood risk beyond JBA’s standard return periods.
• Updated defended area data to complement the hazard maps, which includes new defence information from the EA, SEPA, and NRW, as well as new Standard of Protection and assumed defence coverage assumptions.
• An updated backlog of deterministic events which includes new historic events to aid model validation and back testing, including Storms Ciara, Dennis and Jorge, the 2019 November flood, and Storms Desmond, Eva and Frank. New scenario events are also available for stress testing, including Thames Barrier failures. These new events accompany the standard UK Flood Event Set, which includes over 100,000 events with a 504 hours clause.
• New vulnerability data includes updated built environment data for 2020, which is used to assign vulnerabilities to locations with unknown risk types, as well as new engineering vulnerability curves to accompany standard residential, commercial industrial, motor, and agricultural risk types.

New methods

Our team of flood experts have developed a range of new methods for the latest UK Flood Model which capitalises on the flexibility of JBA's modelling technology, enabling improved representation of uncertainty, flood extents and severity, and analysis:

• Moving away from the traditional, rigid method of estimating uncertainty by sampling from predefined distributions and instead using the uncertainty in the actual data to inform the uncertainty in the loss. This method perturbs depth and damage ratios by scaling values, runs an ensemble of the perturbations, and calculates uncertainty form the ensemble output.
• Three flood defence options – undefended, defended with some overtopping, and the new probabilistic defence failure method. This new method represents defences that can fail per event probabilistically, based on defence type, condition of defence and return period of event, for the most extreme view of flood risk.
• New methods for each level of analysis – location, aggregate and detailed site level. Each method accounts for the unique requirements of the different analysis levels and user needs.

New climate change view

Users can also assess future risk via a new climate change view, which is an optional component of the UK Flood Model. This climate change view will provide an indication of potential future changes in flood risk and losses by 2050 under climate scenarios RCP4.5 and RCP8.5.

This focuses on our area of expertise – the impacts of climate change on the physical risk of flood.

Developed using government, peer-reviewed climate data in the UK, the climate change view is available as an event set that can be substituted in during analysis.

This allows better understanding of the impact of climate change on a portfolio or at individual risk level, and the ability to build resilience over time, answering questions like:

• How much do I charge for the same risk in the future?
• How much capital do I need to support my existing portfolio under a future scenario?
• Do I need to start shifting my portfolio?
• What products do I need to develop?
• What forms of adaption are required to limit risk?

New access options

The probabilistic UK Flood Model is available via JBA’s new User Interface, as well as updated offerings from Oasis LMF, Nasdaq Risk Modelling for Catastrophes, and ELEMENTS from Aon's Impact Forecasting team.

These complement JBA’s standard consultancy offering.

How can the UK Flood Model help me?

• Competitive pricing
• Exposure accumulation management and geographical hotspot identification
• Portfolio planning, diversification and optimisation
• Capital management
• Solvency and regulatory requirements
• Deep dive, scientific and ‘What if?’ investigation

Keep an eye out for our next blog, which will explore the different user customisation options in more detail. If you'd like more information about the model or would like to discuss a test and evaluation free trial, get in touch with the team.