The wind risk assesses a site's chronic windiness: constant winds, even if not extreme, exert continuous stress on infrastructure and crops and favour soil erosion. It is measured by estimating how rare, relative to the historical climate, the wind value expected in the future is: the rarer the event (the longer the return period), the higher the risk.
Indicator. Return period (years) of the near-surface wind speed (sfcWind, 10 m), annual mean.
Data. Daily sfcWind CMIP6 from the Copernicus Climate Data Store (CDS), aggregated to a multi-model annual mean. Historical baseline: 1950–1970. Scenarios: SSP1-2.6 / SSP2-4.5 / SSP3-7.0 / SSP5-8.5, up to 2100.
Calculation.
(1) A GEV (Generalised Extreme Value) distribution is fitted to the yearly mean wind speeds (sfcWind) of 1950–1970, taking for each year the highest yearly mean among the climate models (21 values).
(2) For each future year/scenario the highest yearly mean among the models is taken and its return period is computed via the GEV survival function (RP = 1 / GEV.sf), capped at 250 years.
(3) The return period is classified into levels.
Thresholds → level A–F.
• Based on the return period (years), thresholds [2, 5, 10, 25, 50]: A: RP < 2
• B: 2–5
• C: 5–10
• D: 10–25
• E: 25–50
• F: ≥ 50.
The 2 / 5 / 10 / 25 / 50-year thresholds are a xNatura choice without a published source. The value shown is the mean of the models, while the class uses the highest value among the models.
From physical to impact. The physical level (A–F) is combined with the production process's sensitivity through the risk matrix (6 physical levels by 5 sensitivity bands) → impact level; the damage curve converts the level into a damage factor, from which the Version 2025 value at risk is derived. The damage factor per class is an xNatura estimate without a published source: the value is indicative.
Sources.
• [Climate Change 2021: The Physical Science Basis](Climate Change 2021: The Physical Science Basis)
• [Fatigue of Structures and Materials](Fatigue of Structures and Materials)
• [Soil Erosion by Wind](Soil Erosion by Wind).
Indicator. Return period (years) of the near-surface wind speed (sfcWind, 10 m), annual mean.
Data. Daily sfcWind CMIP6 from the Copernicus Climate Data Store (CDS), aggregated to a multi-model annual mean. Historical baseline: 1950–1970. Scenarios: SSP1-2.6 / SSP2-4.5 / SSP3-7.0 / SSP5-8.5, up to 2100.
Calculation.
(1) A GEV (Generalised Extreme Value) distribution is fitted to the yearly mean wind speeds (sfcWind) of 1950–1970, taking for each year the highest yearly mean among the climate models (21 values).
(2) For each future year/scenario the highest yearly mean among the models is taken and its return period is computed via the GEV survival function (RP = 1 / GEV.sf), capped at 250 years.
(3) The return period is classified into levels.
Thresholds → level A–F.
• Based on the return period (years), thresholds [2, 5, 10, 25, 50]: A: RP < 2
• B: 2–5
• C: 5–10
• D: 10–25
• E: 25–50
• F: ≥ 50.
The 2 / 5 / 10 / 25 / 50-year thresholds are a xNatura choice without a published source. The value shown is the mean of the models, while the class uses the highest value among the models.
From physical to impact. The physical level (A–F) is combined with the production process's sensitivity through the risk matrix (6 physical levels by 5 sensitivity bands) → impact level; the damage curve converts the level into a damage factor, from which the Version 2025 value at risk is derived. The damage factor per class is an xNatura estimate without a published source: the value is indicative.
Sources.
• [Climate Change 2021: The Physical Science Basis](Climate Change 2021: The Physical Science Basis)
• [Fatigue of Structures and Materials](Fatigue of Structures and Materials)
• [Soil Erosion by Wind](Soil Erosion by Wind).