There are different ways in which vulnerability and risk can be defined and analysed. In climate change publications, vulnerability is often defined as a function of the character, magnitude, and rate of climate variation and change to which a system is exposed, together with its sensitivity and adaptive capacity. Humans can increase their vulnerability by urbanisation of coastal flood plains, by deforestation of hill slopes or by constructing buildings in risk-prone areas. Publications in other areas, such as those relating to natural hazards, tend to define vulnerability as an inherent characteristic of a social system or societal group. 

A common means of measurement of the risk of a natural hazard is as follows:

Risk of the hazard = Expected damage of the hazard x Probability of the hazard occurring.

In the case of climate change projections, considerable complexities arise in the calculation of the risk function. These are associated with assigning probability to certain climate change scenarios and with making assumptions about the impacts of future socio-economic development. Given the differences in defining and applying vulnerability and risk assessments, the CLIMATE-ADAPT platform does not enforce a strict definition of vulnerability. A broad overview of vulnerability and natural hazard risk assessments is presented in this section and access is provided to guidance for conducting a vulnerability assessment.

For specific information about statistics and scenarios for climate change vulnerability in specific sectors, see water, cryosphere, terrestrial biosphere (including biodiversity, agriculture and forestry), oceans, or urban areas and health.

Note: much of the information accessible via these pages does not specifically relate to climate change vulnerablity and risks, but can provide background information to determine those risks.