Answer:
True
Step-by-step explanation:
From the point of view of the current methodology, a frequent error that occurs in the analysis of volcanic risk is to associate it with seismic risk, when they only have in common the most spectacular natural disasters belonging to the internal activity of the planet. An essential difference between the two is that while the seismic risk represents a unique danger (the earthquake) and almost instantaneous, the volcanic eruption can last for months and the danger factors it possesses are multiple: lava flows, flows of pyroclasts and ash fall, lahars and avalanches, gases, volcanic earthquakes, tsunamis, thermal anomalies, soil deformations, etc.
Risk could be defined as the expectation that certain events produce a negative impact on the exposed anthropic elements of an area; therefore, if man or his infrastructure is not present, there would be no risk. This analysis is made from the study of events that occurred in the past and extrapolated to the current period, with economic interests being the parameter used to quantify the final risk. According to current knowledge, the problem of risk analysis is framed in a probabilistic field that must be linked to the deterministic study of the phenomenon. Thus, the risk will always have a numerical value (monetary or number of victims) that can be calculated from the formulas used according to the methodology followed and its quantification is determined by the previous calculation of the danger, vulnerability and exposure, being the first the result of the product of the final three.
Risk = danger * vulnerability * exposure
Danger
Danger can be defined as the probability that a place, in a given time interval, will be affected by a dangerous event.
Exposition
It represents the value of the goods subject to possible losses, their value being zero when there is no good present in the area affected by a natural phenomenon.
Vulnerability
It is the expected percentage of damage (loss) that the exposed assets will suffer if the event occurs and is expressed in% of the total value of the element at risk. This value, being a statistical concept, must be calculated for all similar elements