The vulnerability can be defined as “conditions determined by physical, social, economic and environmental factors or processes which increase the susceptibility of an individual, a community, assets and/or systems to the impacts of hazards (United Nations General Assembly, 2016)”.

The vulnerability assessment uses the same categories as the ‘exposure assessment’ (see Step 2). The analysis is based on the selection of prioritized weather-related risks and the exposure assessment. It encompasses a variety of concepts and elements, with various international methods developed to include variant factors such as:

• Physical dimensions − refer generally to the quality and strength of physical structures (and affected human beings). This includes buildings, productive assets (e.g. equipment, stock), and infrastructure relevant to the agricultural value chain (e.g. roads, dams, flood defences).
• Economic dimensions − refer at the micro level to livelihood patterns of house¬holds at risk (e.g. source of income which may incur higher losses) and the private sector dependency, such as business interruption of SMEs (see Box 1, below). At the macro level, they refer to the vulnerability of an economic system and its capacity to absorb and deal with a specific damage or loss. Overall, impacts on all levels affect the gross domestic product, level of income/tax revenues, and general access to external finance, which is crucial after an event.

Box 1: Cost Calculation for Business Interruption Losses

The total cost per hectare is useful as a proxy for assessing business interruption losses, especially for fruit trees and permanent plantations affected by disasters. To quantify the importance of each crop for the agricultural sector, information on production value for all the crops needs to be collected. These average costs are not representative of subsistence farmers that use fewer inputs, and therefore have fewer production costs, or commercial farmers that use inputs intensively and obtain higher prices when selling their products on the export markets. Respective margins have to be added or deducted (World Bank/ADB/SPCCPS, 2013).

• Environmental dimensions − refer to the disruption of livelihoods and other societal processes due to degradation of environmental services and function (e.g. the effect of deforestation causing higher ground temperatures, potentially resulting in drought). They further refer to the role of regulating ecosystems services for people exposed to disaster risks and climate change.
• Institutional dimensions − refer to ‘systems’ and governance structures, including an enabling environment, and the capacity of (formal) institutions to manage risks and adapt to challenges (e.g. early warning systems). In addition, decision-making processes such as participation, responsiveness, transparency, and interactions between governmental and NGOs (especially those involved in DRM, CCA and sustainable agricultural development).
• Social dimensions − refer to factors that make responding to a hazard event easier or more difficult such as initial well-being (e.g. nutritional status, health), livelihood and resilience (e.g. education, qualification, poverty and access to social-protection), self-protection (e.g. capability and awareness), social networks and institutions (e.g. farmers’ organizations). They also include discrimination on the basis of gender, ethnicity and age, and migration and displacement.

The analysis also includes assessing the spillover of weather-related impact on agricultural sectors e.g. flood damages on transport infrastructure that disrupts the supply of agricultural products in distant regions.