Improving statistical models for flood risk assessment Ross Towe 1,2 Jonathan Tawn 1 Rob Lamb 1,3 Chris Sherlock 1 Ye Liu 4 1 Dept. Mathematics and Statistics, Lancaster University, Lancaster, UK 2 JBA Trust, Broughton Hall, Skipton, UK 3 Lancaster Environment Centre, Lancaster University, UK 4 JBA Risk Management, Broughton Hall, Skipton, UK October 2016
1. Improving statistical models for ood risk assessment Ross
Towe 1,2 Jonathan Tawn 1 Rob Lamb 1,3 Chris Sherlock 1 Ye Liu 4
1Dept. Mathematics and Statistics, Lancaster University, Lancaster,
UK 2JBA Trust, Broughton Hall, Skipton, UK 3Lancaster Environment
Centre, Lancaster University, UK 4JBA Risk Management, Broughton
Hall, Skipton, UK October 2016
2. Motivation Credit: BBC NEWS Credit: Barry Hankin, JBA
Consulting
3. KTP Project Two year project between JBA Consulting, JBA
Trust and Lancaster University Aim of the project is to improve the
efciency and applicability of statistical models for ood risk
assessment Incorporate rainfall information into the existing
models for ood risk assessment Challenges relate to data
availability and quality
4. Motivation What is the probability of multiple locations
observing a 1 in 100 year ood event? What is the probability that a
location will simultaneously experience an extreme rainfall and
river ow event?
5. Motivation What is the probability of multiple locations
observing a 1 in 100 year ood event? What is the probability that a
location will simultaneously experience an extreme rainfall and
river ow event? F = (F1, . . . , Fd ) are observations of river ow
X = (X1, . . . , Xn) are observations of rainfall We can model the
joint dependence between river ow and rainfall
6. Motivation Can t a statistical model to the river ow gauges
to provide us with predictions of plausible future ood events Need
predictions of the future ood events at ungauged locations qq q q q
q q 51.5 52.0 52.5 53.0 4 3 2 Longitude Latitude 50 100 150
ReturnPeriod
7. Motivation Can t a statistical model to the river ow gauges
to provide us with predictions of plausible future ood events Need
predictions of the future ood events at ungauged locations Existing
statistical method interpolates through using river ow information
Limitations: Missing data Lack of nearby gauges qq q q q q q 51.5
52.0 52.5 53.0 4 3 2 Longitude Latitude 50 100 150
ReturnPeriod