If, when (a future date or frequency) and how (intensity or magnitude and/or duration) of an external shock, for example an epidemic (viral in origin, i.e. COVID-19 SARS-CoV-2 coronavirus, Ebola virus disease (EVD) and Ebola hemorrhagic fever (EHF) caused by ebolaviruses, etc.) or non-epidemic disaster (natural, anthropic or technological, or a combination of, in origin, i.e. hurricane, flood, earthquake, etc.) strikes a particular region depends on statistical representations of historical event characteristics (probability or distribution), (climate model) as well as spatial and temporal factors. The most important factor associated with exposure are the numbers of people and assets (in terms of wealth) exposed to (spatial and temporal or time and place) the hazard, and their vulnerability to be damaged or loss of life. In the case of flooding, storm surge, tsunami’s and torrential downpours exposure means that human and animal population as well as accumulated wealth in close proximity of the coast, rivers (delta’s) or basins and low lying regions.
Both short- and long-term drought events can affect human as well as livestock populations, food security, assets, production or goods, i.e. agriculture or crop yield and production, water consumption for industrial production and other sectors of activity. There is also environment damage, i.e. ecological units or natural habitats. Drought exposure is a matter of seasonality and geographic distribution (spatial and temporal). Worldwide more and more arable land is being encroached on by expanding deserts. Southern US, Australia, Southern Europe, arid Latin American countries, many African and Asian countries are affected by drought hazard, which can be a result of accelerating desertification that is a consequence of global warming attributed to climate change. Other threats of the exposure to drought are wildfires and water stress. Faced with increasing drought and limited access to fresh water, many government are/will be forced to facilitate mitigation, adaptation and resilience strategies into public plans and development policies.