Searches User Guide: ClimateIndex (reports produced prior to 27/06/2024)
ClimateIndex
ClimateIndex is a weighted sum model based on 3 physical risks: flood, subsidence and coastal erosion, over 2 time periods: 5 and 30 years. It provides a property specific rating from A to F, with A being no risk predicted to F being severe/existential.
The 3 physical risks are also based on what the Bank of England/Prudential Regulation Authority used in their stress testing scenarios.
In order to forecast how climate change can contribute to a changing climate, Representative Concentration Pathways (RCP’s) are used which show how warm the planet is forecasted to get by 2081-2100, based on different emission scenarios. These are set by the Intergovernmental Panel on Climate Change (IPCC).
Surface Water Flooding, River Flooding & Coastal Flooding
The data provides flood risk information from river, coastal (this includes tidal influenced waters) and surface water flooding for a range of future time periods and emissions scenarios (Low emissions - RCP 2.6, medium and most likely emissions - RCP 4.5, and high emission - RCP 8.5).
The temperature increases shown for each scenario are predicted increases by 2081-2100. The models are based on the UK Climate Projections 2018 (UKCP18). It is plausible that climate change will increase the severity and frequency of flood events in the future.
Data update schedule: Annually
Ground Instability
The BGS GeoClimate: shrink–swell national datasets show the potential changes in subsidence risk due to climate change.
They have been developed by combining long-term UK Climate Projection (UKCP) scenarios for rainfall and temperature changes with the geotechnical properties of the ground, to identify areas projected to experience the largest increases in susceptibility to subsidence over the next century.
Shrink swell subsidence needs one crucial factor to be present, in order for the risk to even exist. That is the presence of clays within the soils and underlying geology. The presence of certain clays can mean that in times of wetter weather, excess water can be absorbed into the clays causing them to swell and expand, this can cause upwards movement or heave within the ground which in some cases, may cause potential ground stability issues.
In dryer, hotter weather, the natural level of moisture within these clays can reduce as the ground dries out. This can cause the clays to shrink and contract which may lead to downwards movement known as subsidence. With a possibility of also directly impacting structural integrity of buildings and land.
Should we continue to experience an increase of hotter and therefore dryer weather, we could potentially see an increase in the shrink swell subsidence, more so than if rainfall remained in a more average, stable state.
Classifications used:
| Classification | Explanatory text |
| Highly Unlikely | It is highly unlikely that foundations will be affected by increased clay shrink-swell due to climate change. |
| Unlikely | It is unlikely that foundations will be affected by increased clay shrink-swell due to climate change. |
| Likely | It is likely that foundations will be affected by increased clay shrink-swell due to climate change. |
| Highly Likely | It is highly likely that foundations will be affected by increased clay shrink-swell due to climate change. |
| Extremely Likely | It is extremely likely that foundations will be affected by increased clay shrink-swell due to climate change. |
The classifications do not equate to a percentage likelihood of occurrence as the classes combine a range of soil moisture deficits and propensities to change volume, and therefore cannot be categorised in this way. They are qualitative subjective expert assessments based on quantitative results.
Data update schedule: Quarterly
Coastal Erosion
Defined as the loss or displacement of land, or the long-term removal of sediment and rocks along the coastline due to the action of waves, currents, tides, wind-driven water, waterborne ice, or other impacts of storms.
This data is based on the National Coastal Erosion Risk Mapping (NCERM).
This data shows potential erosion extents from the coastal baseline for the below time periods and degrees of likelihood. E.g. “There is a 95% chance the property will be impacted by coastal erosion in the short term”. The 3 degrees of likelihood are shown for each time period.
Time periods
0 - 20 years (short term)
20 - 50 years ( medium term)
50 - 100 (long term)
Degrees of likelihood
5%
50%
95%
Climate change is expected to cause more frequent and extreme erosion events over time. Buying a property in close proximity to a vulnerable coastal area may have a significant impact on the availability of both a mortgage and insurance for the property. In worst case scenarios the property may even become uninhabitable in the near future.
Further information on sea defences and maintenance may be available in the relevant Shoreline Management Plan (SMP).
Consideration of how coastal erosion could impact the essential infrastructure in proximity to the property (roads, paths, utilities etc) should also be considered as this in turn could restrict access and full use of the property.
Data source: Environment Agency & Natural Resources Wales
Data update schedule: Quarterly
EPCs
An Energy Performance Certificate (EPC) contains information about a property's energy use and typical energy costs, alongside any recommendations to improve a buildings performance if included. EPCs are rated from A (most efficient) (A+ for non-domestic) to G (least efficient) EPC's are valid for 10 years or until a newer EPC is produced.
EPCs are a legal requirement when a property is built, sold or rented (some exceptions do apply).
Further information is available here for domestic properties and here for non-domestic.
Data update schedule: Monthly