From Vulnerability to Adaptation to Climate Change: Food for Thoughts in Social Sciences - Vulnerability of Coastal Ecosystems and Adaptation - page 227

quoting K. Hewitt 2 ). The role of poverty was mentioned among other
factors and through it, the social and economic processes associated
with it. So the socio-cultural dimension of vulnerability to natural
hazards emerged and imposed the need for a differentiation between
the physical processes (hazards) and the human processes
(vulnerability). The traditional formula 'Risk = Hazard *
Vulnerability' incidentally arose from the development of this
concept. The neat separation between physical and human-related
processes however turned out to be unsatisfactory in that it does not
lead to the understanding of why the various groups within a single
population experienced the impacts of the same hazard differently; in
other words, why did they exhibit different degrees of vulnerability.
Therefore, a third concept appeared in the 1990s, which led to the
complex paradigm or the mutuality paradigm . In this case, the mutual
aspect of physical and human processes was emphasized thereby
pointing out that if the hazard exerts any direct influence on the way a
society functions, human activities in turn affect the probability of
a hazard being triggered, in other words of a disaster occurring. At a
local scale, this principle of mutuality is particularly evident when
looking at issues of coastal erosion. Although fighting this
phenomenon, which is first and foremost inherent to the natural
shortage in sediments, requires the deployment of groynes and
seawalls, perversely, the observed effect of these defense strategies is
the worsening ability to maintain sand in the medium-term, which
reinforces the initial erosion problem. On a global scale, human
activities reinforce the greenhouse gas concentration in the
atmosphere, which increases temperatures in the lower atmosphere
and the surface of marine water on the one hand, and an acceleration
of glacier melting on the other hand. These phenomena act in
combination to explain sea level rise. Both examples show that the
physical processes (the hazards) and the human processes affect each
other more than if they only interacted at any one particular moment
in time, i.e. when the hazard occurred [BLA 94]. Although the
mutuality paradigm undeniably made a breakthrough in enabling
the concepts of risk and vulnerability to move forward, it also made
2 [HEW 83].