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Assessing climate change risks and vulnerabilities

2.1 Understanding climate risks

The terminology and concepts in this chapter follow the most current climate risk concept of the IPCC, as referred in IPCC AR5 in 2015. However, some existing climate risk and vulnerability assessments are still based on older concepts such as the climate vulnerability concept from IPCC AR4, but follow more or less a similar concept. One advantage of the IPCC AR5 climate risk concept is its consistency with the Disaster Risk concept, which is widely used in the context of Disaster Risk Reduction (EEA Report No 15/2017).

Climate risks, according to the IPCC, are potential adverse consequences for human or ecological systems caused by climate extremes and climate change. A climate risk (e.g. drought damage in agriculture) results from interactions between climate-related hazards (e.g. the frequency and intensity of droughts) with exposure (e.g. agriculture land) and vulnerability (e.g. drought resistance of crops, presence or absence of irrigation) of natural and human systems.

Source: IPCC, 2014: Summary for policymakers.

A climate risk is the result of three different factors: hazard, exposure and vulnerability.

A hazard is the potential occurrence of a climate related event or trend or its physical impact that may cause loss of life, injury, or other health impacts, as well as damage and loss to property, infrastructure, livelihoods, service provision, ecosystems, and environmental resources. Events are climate hazards such as droughts, heatwaves, heavy rain events or storms. Trends are slow onset change such an increase in mean temperature, sea level rise or an increasing aridity of a region.

Exposure describes the presence of people, livelihoods, species or ecosystems, environmental functions, services, and resources, infrastructure, or economic, social, or cultural assets in places and settings that could be adversely affected.

Finally, the risk depends on the vulnerability of the exposed system and its elements. Vulnerability describes the propensity or predisposition to be adversely affected. Vulnerability encompasses a variety of concepts and elements including sensitivity or susceptibility to harm and lack of capacity to cope and adapt.


An agricultural area is potentially affected by frequent and intense drought events with an absence of precipitation and high temperature, which causes yield losses and loss of income for farmers.

The hazard is the drought itself, described by a precipitation deficit (meteorological drought), a resulting soil moisture deficit (agricultural drought) or low flows in rivers (hydrological drought).

Exposure can be expressed by proportion of agricultural land potentially affected by a drought or by the proportion of people which depend on income from farming.

The vulnerability of the system depends on many factors like:

  • natural factors such as the drought resistance of crops
  • technical factors such as the presence or absence or the efficiency of an irrigation system
  • factors related to the capacity of farmers to cope and adapt such as the availability of insurance schemes or the options for a second income from tourism. 


Climate-ADAPT database items

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