Graphical Instruments for a timely adaptation to Climate Change

Abstract

Despite all
research efforts, climate change remains unpredictable in the long term.
Climate change unpredictability  raises
serious concerns for policymakers that prepare long-term policies. To guarantee
that climate adaptation  policies perform
satisfycingly despite the unavoidable uncertainty, adaptive policies might be
used. Adaptive  policies are designed to
be adapted over time in response to how the future is actually unfolding.
Signposts are  used to track exogenous
developments that critically affect the performance of a plan, and when
pre-specified  triggers are reached the
policy is adapted. This so-called monitoring system is used to gather evidence
of change,  on the basis of which a
policy is adapted. The ability of the monitoring system to effectively detect
change is  pivotal to the success of the
whole adaptive policy.  A decision-maker
would like to have sufficient confidence about the future capacity to adapt the
policy on  time. On time means adapting
the policy not too early for that incurs unnecessary costs, nor too late which  incurs avoidable damages. The capacity to
adapt the policy on time is to be tested before the adaptive policy is  implemented. Despite the substantial and
growing attention by researchers for supporting the making of climate  adaptation decisions under uncertainty, the
ex-ante evaluation of the degree to which the monitoring system  enables timely adaptation has been largely
overlooked.  We present innovative
graphical instruments to assess ex-ante the level of confidence that a
monitoring system for  adaptive policies
will offer at the moment at which adaptation is required: the
Trigger-Power-Significance (T-PS)  plot
and the Trigger-Consequences (T-C) plot. These instruments explore the
interplay between the possible  trigger
values of a given signpost and the level of confidence about the need for
adapting the policy. We illustrate  how
these instruments can be used to test the effectiveness of a monitoring system,
and how they can be integrated  into the
process of designing an adaptive policy. 
The use of the proposed instruments and approach are demonstrated using
a case study of designing an  adaptive
policy for coastal flood protection in the Netherlands. This application shows
the effectiveness of these  instruments
in evaluating ex-ante the capacity of a monitoring system to provide the
information required to adapt  on time
with sufficient confidence, and redesign it if this is not the case.