Uncertainty analysis in the Thames Estuary Lucy Manning and Hamish Harvey School of Civil Engineering and Geosciences, Newcastle University Jim Hall Environmental.

Uncertainty analysis in the Thames Estuary

Lucy Manning and Hamish HarveySchool of Civil Engineering and Geosciences,

Newcastle University

Jim HallEnvironmental Change Institute, Oxford

University

1

IPCC AR4 mean sea level projections

2

AR

4 20

07 Does the UK experience the global mean?

Plus additional contribution

from ice sheets ?????

3

TE2100 adopted a High++ scenario of 2m mean sea level increase in 2100

Ice sheet melting beyond 2100

4

What would this mean for closure of the Thames Barrier?

5

For what sea level rise scenarios does gravity drainage continue to work?

6

Decision analysis under uncertaintyWe consider a two-stage problem:

• Conventional cost-benefit analysis is applied for the appraisal period considered in TE2100 (i.e. to 2170)

• We recognise the possibility of long term in vulnerability to high levels of sea level rise. We wish to avoid situations of unacceptable societal risk that society may regret in future.

We analyse 1000s of different decision pathways (barriers, defence raising, pumping), along with non-structural measures

We provide decision makers with information on ‘short-term’ optimisation and ‘long-term’ regret.

We demonstrate how to identify robust flood risk management strategies in complex situations of decision making under uncertainty

See our first FRMRC Fact Sheet…more results to follow