100årshändelse

A 100årshändelse, literally translating to "100-year event," is a term used in various contexts to describe occurrences that are statistically rare, with an expected frequency of once every century. This concept is often applied in fields such as hydrology, geology, and risk assessment. For instance, a 100-year flood refers to a flood event that has a 1% chance of happening in any given year. It does not mean that such a flood will only occur once every hundred years, but rather that it is a level of severity with that specific probability.

The term is a statistical construct and is crucial for planning and infrastructure development. Engineers and planners use 100årshändelse probabilities to design structures like dams, bridges, and flood defenses that can withstand extreme events. This helps to minimize damage, loss of life, and economic disruption. While the term suggests a fixed interval, it's important to remember it's based on probabilities derived from historical data and statistical models, which can be influenced by climate change and other environmental factors. Therefore, the actual frequency of such events may deviate from the calculated century-long average.