Subsidence susceptibility (global, Herrera GSS)
This layer maps how prone the land is to sinking gradually as a result of groundwater depletion.
Source: Herrera-García et al. (2021), Global Subsidence Susceptibility Year: 2010 Category: Physical risks · Mitigating services · Geological Coverage: Global Format: Raster grid (~1 km) Used in risk analysis: Yes — gates Mitigating services
What it shows
This layer maps how prone the land is to sinking gradually as a result of groundwater depletion. Land subsidence can damage foundations, pipelines, drainage and other infrastructure over time, and can worsen flood exposure in low-lying areas. It matters for nature-related risk because it identifies where reliance on groundwater and the underlying geology combine to threaten ground stability. It is distinct from clay shrink-swell, which is covered by a separate layer.
How it is built
The layer is the Global Subsidence Susceptibility map (Herrera-García et al., 2021), modelling the probability of groundwater-depletion-driven subsidence for the year 2010. The modelled probability is grouped into six equal-interval classes ranging from very low to very high. The result is a screening surface that highlights broad zones of elevated susceptibility rather than confirmed subsidence at any single point.
How to read it
Values run across six classes: very low, low, medium-low, medium-high, high and very high. Higher classes indicate land more likely to subside where groundwater is drawn down. This is a screening layer, not a siting tool — a high class flags the need for closer geotechnical investigation rather than confirming subsidence will occur.
Class thresholds
The underlying quantity is the modelled probability of groundwater-depletion-driven land subsidence (for the year 2010) — a dimensionless probability, not a physical flux. Herrera-García et al. group that probability into six equal-interval susceptibility classes:
| Value | Class |
|---|---|
| 1 | Very low |
| 2 | Low |
| 3 | Medium-low |
| 4 | Medium-high |
| 5 | High |
| 6 | Very high |
A site is flagged on the Mitigating services dimension when the layer reaches class ≥ 5 (High or Very high) (template: "High land-subsidence susceptibility zone (Herrera GSS class >= 5)").
How these thresholds were set. The six-class structure is an equal-interval binning of the modelled subsidence probability, defined by the Herrera-García et al. (2021) Global Subsidence Susceptibility methodology; the underlying probability cut-points that separate the classes are set in that publication and are not reproduced in Darwin's configuration. The class-5 flag (escalating on High and above) is a Darwin choice applied to those classes.
Reference: Herrera-García et al. (2021), "Mapping the global threat of land subsidence", Science.
Source
Herrera-García et al. (2021), "Mapping the global threat of land subsidence", Science; Global Subsidence Maps (figshare, CC-BY licence).
Comparison with the WWF Risk Filter Suite
The WWF Risk Filter Suite has no equivalent indicator. Subsidence is a geophysical hazard rather than a biodiversity or water risk in the WWF methodology. This is a Darwin extension that broadens physical-hazard screening beyond the WWF set.
Risk analysis
A site is flagged on a dimension by combining a proximity trigger (this layer) with an activity trigger (the entity's ENCORE pressure/service). Proximity only → Potentially material; proximity and the matching ENCORE pressure/service is material → Very material; neither → Not material.
| Dimension | ENCORE service / pressure | Proximity trigger (this layer) | Activity trigger (entity) |
|---|---|---|---|
| Mitigating services | Land subsidence | Layer value above 5 | — |
Legend
Symbolised field: Subsidence susceptibility
| Value (Subsidence susceptibility) | Label | Colour |
|---|---|---|
| 1 | Very low | #ffffcc |
| 2 | Low | #d9f0a3 |
| 3 | Medium-low | #fee08b |
| 4 | Medium-high | #fdae61 |
| 5 | High | #f46d43 |
| 6 | Very high | #d73027 |
Generated from darwin/layers/layer-subsidence-global.toml and risk_indicator_pairs.toml (develop).