In the following, we will first introduce LSL as the relevant impact parameter in the context of the anticipated climate change. Establishing an equation linking LSL to the various forcing processes will emphasize the complex nature of this parameter. In the light of this complexity and the sparse observations of LSL, the global averages are associated with large uncertainties, and so are the modeled or derived global contributions of the various factors. In this situation, where we face both large aleatory and epistemic uncertainties, we can apply a scenario-based approach in order to put some boundaries on plausible future LSL changes. For a given location, we can look at the individual forcing factors and make assumptions (i.e., set up scenarios) about their future importance. Unfortunately, the individual forcings are all associated with relatively large uncertainties. We will illustrate that on the basis of an example, the Dutch Coast. Analyzing the uncertainties, we see that all five types of uncertainties identified by Manning and Petit (2003) are relevant for both, understanding the past and predicting the future, and hampering the planning of mitigation and adaptation.