Hazards, Vulnerability and Risk

Abstract

The hazards and vulnerability concepts are introduced after a brief review of the definition of risk. Hazards are essentially associated with any natural phenomenon investigated, while vulnerability is primarily a socioeconomic parameter influenced by other drivers of change such as demography. The risk concept derives from these two parameters. Given that there is no such thing as a zero risk situation, it is essential to introduce the idea of an acceptable level of risk which must be determined through a participatory process set in motion by society. Knowledge regarding these two risk components is dependent on the methods used to assess them and associated levels of uncertainty. The impact of climate change on hazards is hard to quantify because, under a constant climate, it is generally an order of magnitude below the natural existing uncertainty. Conversely, vulnerability is not well understood and few rigorous methods are available to quantify this factor. Clarifying hazards thus may seem to enhance the risk assessment but this is illusory since the less understood vulnerability factor is overlooked, which may lead to too much attention being focused on the hazards factor to the detriment of vulnerability management. This may also apply to other climate risks such as drought, although flooding risk is better understood. These considerations may be useful for the agricultural community which, besides its production function, could offer society other services of territorial scope, encompassing different areas, while in return benefitting from support measures that would make the risks more acceptable.