What is the difference between public flood maps (such as Environmental Agency flood maps) and commercial flood risk data?
Flood maps are produced by many different organisations, including commercial companies such as JBA, and public bodies such as the Environment Agency. Each set of maps will differ depending on the starting data and assumptions made by the modeller.
Is flood risk data available globally?
Flood risk data is available globally through consistent hazard maps and event sets that cover multiple flood types. These datasets support comparisons at global, continental, and national levels, with regional high‑resolution components where available. JBA provides global flood maps and catastrophe models designed to support international exposure analysis and decision‑making.
How frequently are flood maps updated?
Flood maps are updated as frequently as possible to incorporate new modelling methods, third‑party data, climate adjustments, and improvements in baseline terrain or hydrology inputs. The programme of updates is part of a continuous improvement process to ensure that flood maps and related datasets remain current and scientifically defensible.
How can businesses use flood risk data to meet regulatory and disclosure requirements?
Businesses use flood risk data to identify exposure, assess potential financial impacts, and support disclosures required under frameworks such as TCFD, ISSB, and EU sustainability regulations. The data helps identify and assess potential climate -related physical flood risks and can be accessed in different formats depending on the client need. This might include a visual flood map identifying areas and extents and depths of flooding, qualititive risk scores numbers or traffic light coded risk bands. Access can be via direct licencing a dataset or via online such as an platform viewer or direct delivery by APIs or WMTS. Flood risk data and analysis supports regulatory reporting and scenario assessment enabling evidence-based decision-making across portfolios and individual assets.
What resolution are flood maps and catastrophe models produced at?
Flood maps are produced at a range of resolutions typically from 5m to 30m depending on the region and product. Catastrophe models use the maps alongside event sets that are spatially matched to the underlying hazard resolution. Resolution varies by geography and dataset version. JBA supplies consistent, high‑resolution maps (at 30m globally and at 5m for the UK, Ireland, USA, continental Europe and major regions in Australia) and model inputs to support detailed and portfolio‑scale assessments.
What is the validation process of a flood map?
Flood maps can be validated by assessing whether the input data (e.g. a digital elevation model) and model results (flood maps) are realistic and conform to expectations. This can be achieved through scientific analysis and comparison with high-quality benchmarking data. At JBA Risk Management, we validate the components and product throughout the development cycle so that we are confident that we are creating the highest quality data.
What is off-plain flooding, and is it included in flood risk models?
Off‑plain flooding refers to inundation occurring outside traditionally mapped river floodplains, often driven by surface water or local drainage processes. It represents flood mechanisms not captured by river‑only models. JBA’s modelling framework includes surface water flooding and therefore captures off‑plain processes within its mapped hazard datasets. JBA provides hazard layers that represent multiple flood types consistently across regions.
Does flood data account for climate change and recent flood events?
Flood data can incorporate climate‑driven changes to allow the user to understand potential future flood risk as a result of climate change. This is done by applying return‑period change factors derived from climate model outputs to baseline current day exposure intelligence. These adjustments capture how future rainfall, river flow, and sea‑level conditions may shift flood severity. Recent events are not directly “baked in,” but the climate‑adjusted datasets reflect long‑term trends rather than single occurrences. Recent flood events are not always recognised as a result of climate change.
What is the validation process of an event set?
JBA's approach to the validation of any single event set is normally tens or hundreds of pages long! But we can classify the validation tests into 4 sections: (1) validation of the datasets used to generate the event set; (2) validation of the event set components (e.g. rainfall runoff models, weather data); (3) validation of the event set as a whole (e.g. event set frequencies and severities); and, (4) validation of the results when an event set is incorporated into a cat model. Comparison against observed data (for example, gauge records or historic event extents and severities) is an important component of event set validation, always remembering that the event set should not only mimic but also extend the observed record.
How are flood defences modelled for catastrophe models?
The exact approach used varies by country because of differences in available data and the quality of the defences in that country. However in general, JBA's models always include defence overtopping and sometimes include defence breaching as an additional intelligence layer that can be considered or disregarded as needed.
What is the validation process of a cat model?
Model validation assesses whether the model is scientifically sound, fit for purpose, and capable of producing credible and reliable results for end users. It includes validation of the model components, reviewing key assumptions, evaluating sensitivity behaviour, and comparing outputs against scientific literature, independent benchmarks, and historical event. Validation also ensures that all model components—such as hazard maps, event sets, vulnerability functions, and any climate‑adjusted elements—are coherent and internally consistent. JBA documents validation steps, limitations, and appropriate‑use guidance in formal validation reports across flood products.
How many properties are at risk of flooding worldwide?
Global flood exposure varies by region and dataset, with detailed totals depending on model resolution, hazard type, and exposure data. Internal documentation does not define a single global property count but highlights the use of globally consistent 30 m maps and exposure datasets to understand risk distribution. JBA provides global flood mapping and catastrophe modelling to help quantify exposure across countries.