Geoscience Reference
In-Depth Information
political, social, and economic uncertainties. Such a distinction wrongly implies that
the outcomes of science are independent of the processes that generated them, which
are necessarily subject to social, political, and economic uncertainties.
In common usage,
risk
focuses on the potential negative impacts of being exposed
to harm and is therefore synonymous with loss. It extends the concept of uncertainty
to decision making, where the potential for loss is known (e.g., in terms of time,
money, property, environmental quality or human life) but the precise nature of the
loss, whether it will occur, or even how probable it is, are unclear. In this context,
various technical defi nitions of risk have been proposed in the social and physical
sciences, including the treatment of risk as the probability of an undesirable event
or the probability of an accident multiplied by the expected loss (Bernstein, 1998).
However, risk is often embraced in the pursuit of some gain, and others associate
risk with opportunity and the entrepreneurial balancing of uncertain costs and
benefi ts (Baker and Simon, 2002). While the latter implies choice, the extent to
which risks are chosen, and the ways in which they are managed, will depend on a
range of individual, social and situational factors (Section 4). Similarly, while risk
implies uncertainty about the costs and benefi ts of a decision, this uncertainty may
be unevenly distributed among those involved in, and affected by, a decision. Indeed,
multiple perspectives can originate from disagreement about what a decision
should
achieve, including what represents a good or bad outcome (e.g., more housing versus
more greenbelt land), as much as any uncertainty about the precise consequences
of an action.
As an expression of confi dence, uncertainty will vary between individuals and
groups of scientists and is, therefore, subjective (Brown, 2004). Similarly, percep-
tions of risk vary with personality and culture. This will in turn infl uence decision
making: 'risk perceived is risk acted upon' (Adams, 1995). Uncertainty and risk will
depend on our level of
awareness
or recognition of a 'problem', its perceived impor-
tance, and our apparent ability to resolve it. All of these factors are psychologically
and socially motivated (Section 3). While uncertainty and risk imply that we are
aware of a problem or potential loss, our precise level of awareness may vary, and
it is the interaction of awareness and confi dence that leads to the various expressions
of imperfect knowledge considered here.
Any decision that involves uncertain costs and benefi ts, i.e., risk, entails the pos-
sibility of surprise. An important result of considering awareness and confi dence
jointly is that our capacity to be surprised is endemic, since it may originate from
a lack of awareness, misplaced confi dence, or some combination of the two. For
example, most 'natural disasters' can be attributed to a lack of awareness about
where and when an event will occur and misplaced confi dence about existing levels
of protection. Related to this is the
act of ignoring
, where some information is dis-
missed for reasons of effi ciency, simplicity, or self-interest. For example, a modelling
problem may be simplifi ed by using a limited space-time domain, a fi nite resolution
or a reduced process description. However, in non-linear systems, the impacts of
these assumptions can only be predicted in general terms (and often not at all), such
that the accumulation of uncertainties may ultimately lead to surprise.
A basic result of uncertainty, both in scientifi c research and environmental deci-
sion making, is the presence of multiple possible outcomes or explanations (referred
to as non-uniqueness). For example, a single causal pathway can lead to different
outcomes in different geographical contexts (Von Engelhardt and Zimmerman,
1988). Similarly, multiple causal pathways can lead to the same outcome in any
