Step 2. Assessing climate change risks and vulnerabilities

To determine what your regional or local authority needs to do to adapt to climate change, you need to assess your climate risks. In step 2, you will be guided in how to assess how climate change will affect people, sectors or systems.

Climate risks depend on three different factors (see figure):

• Climate-related hazards - The current climate conditions and how they will change in the future.  These conditions will determine the likelihood of an area being affected by either extreme events, such as heatwaves, or slow onset events such as sea-level rise.:

• Vulnerability - The tendency of the exposed system and its components to be adversely affected. Vulnerability is a product of:

• Sensitivity - The degree to which a system or species is affected, either adversely or beneficially, by climate variability or change. The effect may be direct (e.g., a change in crop yield in response to a change in the mean, range, or variability of temperature) or indirect (e.g., damages caused by an increase in the frequency of coastal flooding due to sea level rise).
• Adaptive Capacity - the ability of people, sectors, or systems to adjust to potential damage, to take advantage of opportunities, or to respond to consequences. Adaptive capacity will differ between risks and sectors, for example, a region that is well prepared to cope with floods may be taken aback by a heat wave.

• Exposure – The presence of people; livelihoods; infrastructure; and assets; or species and ecosystems in places and settings that could be adversely affected. For example, the exposure of vulnerable populations to heat or expansion of residential and economic areas in floodplains.

While hazards are directly determined by climate change, vulnerability and exposure depend on socio-economic factors. Planning adaptation regionally and locally requires an understanding of these three factors, to produce a climate risk assessment.

Such a risk assessment will focus primarily on potential future changes, including:

• an inventory of potentially impacted citizens, sectors (e.g., agriculture, energy, tourism) or systems (both human and natural, e.g. water supply system, food system);

• the likelihood of the impact happening; and

• the resulting consequences.

The assessment of climate risks is best undertaken across citizens, sectors and systems because direct impacts can have cascading effects, meaning that an impact on one part of the system will cause a subsequent impact on another part of the system. In addition, there is also a need to consider transregional impacts and effects that go beyond regional or local authority boundaries, like water catchments, or transboundary risks such as the disruption of imports and exports.

The International Standard ISO 14091 and ISO 14092 set the standards of the various methods and outputs of risk assessments at regional and local levels.

Based on the results of the climate risk assessment, you can identify the main climate threats and start to develop a strategic direction for the adaptation planning. You can then define specific and realistic adaptation objectives to address the climate challenges of your region or city. They should be as measurable and precise as possible because the design (Step 3 and Step 4), the implementation of the adaptation strategy or plan (in Step 5) and its monitoring and evaluation (step 6) are directly linked to the targets.

Further sources of information on climate risk assessments can be found:

• Your national climate vulnerability and risk assessment and the Green Deal Going Local Handbook can help inform your assessment.
• The Vulnerability Sourcebook
• Climate-ADAPT and the JRC Risk Data Hub are rich sources of scientific evidence.
• The EEA Member Country Profiles provide a good overview of approaches implemented. The European Climate Data Explorer, and the Adaptation Dashboard give information on indicators of observed and projected climate change, and on current and future climate-related hazards.
• More information about the projected global climate changes and the impacts on cities and regional authorities can be found in the interactive atlas of the 6^th  report of the Intergovernmental Panel on Climate Change (The Physical Science Basis)