Executive summary

Climate-change vulnerabilities of industry, settlement and society are mainly related to extreme weather events rather than to gradual climate change (very high confidence).

The significance of gradual climate change, e.g., increases in the mean temperature, lies mainly in changes in the intensity and frequency of extreme events, although gradual changes can also be associated with thresholds beyond which impacts become significant, such as in the capacities of infrastructures. [7.2, 7.4]

Aside from major extreme events and thresholds, climate change is seldom the main factor in considering stresses on the sustainability of industry, settlements and society (very high confidence).

The significance of climate change (positive or negative) lies in its interactions with other non-climate sources of change and stress, and its impacts should be considered in such a multi-cause context. [7.1.3, 7.2, 7.4]

Vulnerabilities to climate change depend considerably on specific geographic, sectoral and social contexts (very high confidence).

They are not reliably estimated by large-scale (aggregate) modelling and estimation. [7.2, 7.4]

Vulnerabilities of industry, infrastructures, settlements and society to climate change are generally greater in certain high-risk locations, particularly coastal and riverine areas, and areas whose economies are closely linked with climate-sensitive resources, such as agricultural and forest product industries, water demands and tourism; these vulnerabilities tend to be localised but are often large and growing (high confidence).

For example, rapid urbanisation in most low and middle income nations, often in relatively high-risk areas, is placing an increasing proportion of their economies and populations at risk. [7.3, 7.4, 7.5]

Where extreme weather events become more intense and/or more frequent with climate change, the economic and social costs of those events will increase (high confidence).

Experience indicates that costs of major events can range from several percent of annual regional gross domestic product (GDP) and income generation in very large regions with very large economies to more than 25% in smaller areas that are affected by the events. Climate-change impacts spread from directly impacted areas and sectors to other areas and sectors through extensive and complex linkages. [7.4, 7.5]

Poor communities can be especially vulnerable, in particular those concentrated in relatively high-risk areas (high confidence).

They tend to have more limited adaptive capacities, and are more dependent on climate-sensitive resources such as local water and food supplies. [7.2, 7.4, 5.4]

Industry, settlements and society are often capable of considerable adaptation, depending heavily on the competence and capacity of individuals, communities, enterprises and local governments, together with access to financial and other resources (very high confidence).

But that capacity has limits, especially when confronted by climate changes that are relatively extreme or persistent. [7.4.3, 7.6]

Although most adaptations reflect local circumstances, adaptation strategies for industry and settlement and, to a lesser degree, for society, can be supported by linkages with national and global systems that increase potentials and resources for action (very high confidence). [7.6.6]