Vulnerability is defined in different ways, depending on different research traditions, yet is most often conceptualized as being constituted by components that include exposure to perturbations or external stresses, sensitivity to perturbation and the capacity to adapt. Generally speaking, it includes the attributes of persons or groups that enable them to cope with the impact of disturbances like natural hazards.

Large-scale disasters which exceed the current coping capacity of socio-ecological systems are on the increase. Recent examples include the 2008 and 2011 droughts in Ethiopia and other African countries, China’s great ice storm of 2008, hurricane Sandy of 2012 in the U.S., the European heat wave of 2003, as well as the recent global financial crisis. During the period from 1984 through 2003, the population influenced by natural disasters exceeded 4 billion people, mostly in developing countries. An important feature of these disasters is the striking inequality between the vulnerability of people most exposed to the different disasters and the privileged position of others. While many factors contribute to any specific disaster, there is little doubt that global environmental change triggered by human activities plays a major role.

Increasing risks are one of the most significant aspects of the human dimensions of global environmental change. The willingness to accept them as long as they do not materialize in the immediate present is a defining feature of unsustainable development, given that sustainable development can be thought of as a pattern of development ensuring that humankind meets the needs of the present without compromising the ability of future generations to meet their own needs. Slowing down and ultimately reversing this tendency towards increasing risks is a significant challenge of our time. However, the ability to take huge risks is a precondition of the technostructure that enables humankind to communicate, travel and trade all around the globe, and to produce unprecedented welfare by doing so. But clearly this ability has somehow gotten out of hand. As a result, a major question of fairness arises both with regard to the relation between highly industrialized and less developed countries, and to the relation between present and future generations.

It is a complex issue, because future generations are quite likely to be richer in monetary terms and better off in many other respects than present ones. But at the same time, they are quite likely to face even larger risks than we do presently. The lack of fairness in dealing with risk between generations is compounded by the lack of fairness within present generations. Risks to health, welfare and safety are distributed very unevenly across humankind, and it is hard to justify this distribution by any widely recognized standards. And those parts of humankind that currently face the greatest risks also have less rosy prospects for their offspring. Under these circumstances, there is a long way to go in order to achieve something that deserves the name of sustainable development. The know-how on risk governance that is currently available is certainly helpful to address this situation, but it is hardly sufficient.

The concepts of vulnerability, resilience and adaptation (VRA) are interrelated and have wide application to global change science. Events during the last years as mentioned above, together with the bird flu and continuing droughts in Africa, dramatically illustrate the potential vulnerability of human society to disturbances and variability and VRA are used to analyse these and similar events. Furthermore, understanding VRA, as related to the socio-ecological system, is particularly important given that identifying future trajectories and behavioural changes in the earth system depends on understanding the dynamic interplay between social and ecological components.

Resilience originated as a core concept within ecology and is used by ecologists in their analysis of population ecology of plants and animals and in the study of managing ecosystems. Since the late 1980s, the concept has increasingly been used in the analysis of human–environment interactions, mainly to describe and understand how humans affect the resilience of ecosystems. The term can be further applied within the social context as the ability of groups or communities to cope with external stresses and disturbances as a result of social, political and environmental change.

Adaptation to environmental variability has been a focus of anthropologists since the early 1900s. In the 1990s, scholars began to use the term adaptation for the study of the consequences of human-induced climatic change, without explicitly relating this back to the conceptual origins in anthropology. Adaptation is generally perceived to include an adjustment in social-ecological systems in response to actual, perceived or expected environmental changes and their impacts.

Ultimately, vulnerability, resilience and adaptation are different manifestations of more general processes of response to changes in the relationship between open dynamical systems and their external environment.