AfA480: 2004 Fluvial Flood Depth Climate Change Difference Grid for England

A 5x5 meter geospatial grid shows the difference in modelled fluvial flood depths between baseline conditions and a climate change scenario with a 20% increase in peak flows. This dataset was produced in 2004 using the JFlow hydrodynamic model as part of a generalized project to define Flood Zones for spatial planning across England. It covers a 100x100 km Ordnance Survey grid reference (SJ) and is intended for broad-scale analysis, not site-specific assessments.

Use Cases

• Assessing potential changes in flood inundation extent for strategic planning based on a 2004 climate change scenario.
• Comparing generalized flood model outputs with later detailed local models where they exist.
• Informing high-level environmental impact studies using a 5x5m resolution depth difference grid.

Strengths

• Provides a consistent, England-wide 5x5m grid for a standardized climate change scenario.
• Derived from a specific two-dimensional hydrodynamic model (JFlow) documented in the source.
• Represents a specific historical baseline (2004) for tracking methodological evolution in flood modeling.

Limitations

• The dataset has not been updated since its creation in 2004, and official climate change allowances have since changed.
• Sources conflict on the annual chance of flooding covered, listing both 0.1% (1 in 1000) and 1% (1 in 100) probabilities.
• Critical metadata such as row count, specific license, and detailed column schema are unavailable across all platforms.

Provenance

Source

Environment Agency (UK)

Collection Method

Produced as a by-product of the 2004 generalised modelling project using the JFlow hydrodynamic model.

Time Range

2004

Freshness

Last metadata update recorded as 2026-07-06, though the underlying data is from 2004.

Geography

Covers a 100x100 km Ordnance Survey National Grid reference SJ in England; data for the whole of England was created.