A team of researchers including the CGFI’s Hannah Bloomfield, John Hillier, Len Shaffrey, Francesca Pianosi, Rachel James, Dhirendra Kumar, Adrian Champion and Paul Bates have developed a new flood severity index (FSI), as well as examining correlations between wind and flooding in European and UK extreme weather events.
Key takeaways
- The correlation between wind gusts and precipitation in GB correlation ranges from 0.6–0.8 for daily to seasonal timescales. Correlation becomes lower as metrics become more extreme and impact focused.•
- Across Europe, the timescales at which correlations peak depend on local drivers.
- In a future climate the return period of joint-99th percentile GB flood-wind events reduces from 12.9 to 3.7 years.
Summary
The risk posed by heavy rain and strong wind is now suspected to be exacerbated by the way they co-occur, yet this remains insufficiently understood to effectively plan and mitigate.
The study systematically investigates the correlations between wintertime (Oct–Mar) extremes relating to wind and flooding at all timescales from daily to seasonal.
Meteorological reanalysis and river flow datasets are used to explore the historical period, and climate projections at 12 km resolution are analysed to understand the possible effects of future climate change (2061–2080, RCP 8.5).
A new flood severity index (FSI) is also developed to complement the existing storm severity index (SSI). Initially, Great Britain (GB) is taken as a comparatively simple yet informative study area, then analysis is extended to the full European domain.
