Shipwrecking Probability in Mediterranean Territorial Waters: a Cultural Approach to Archaeological Predictive Modelling

This thesis presents a GIS-based methodology to assess the shipwrecking probability in Mediterranean territorial waters. The study focuses on two scales of analysis to meet the need for a general tool applicable to spatial planning and a more detailed one providing insights for historical and archaeological research. Two sub-questions are addressed for identifying high shipwrecking probability areas: 1. Where would ships be more likely to transit? 2. Where would ships have a higher risk of sinking? Transit probabilities are derived by considering multiple, oftentimes competing criteria that affect mariners’ movements, including the effects of risk perception, thus rejecting the idea that sailors would necessarily choose optimal routes. The sinking probabilities include environmental hazards objectively increasing the risk of shipwrecking.
The overall methodology overcomes some of the main pitfalls of current modelling approaches, namely, the inductive use of shipwreck data without a formal exploration of data biases, the predominant reliance on environmental and economic input variables to the detriment of cultural and cognitive factors, and the unheeded effects of uncertainty and subjective reasoning behind the model building. This study suggests that by explicitly differentiating between actual and perceived risks and accounting for the effects this difference produces in terms of variations from the optimal routes, the predictive ability of the model increases. This model, unique hitherto in the Mediterranean basin, constitutes a valuable tool for optimising maritime spatial planning; it provides an adaptable toolkit applicable to other geographical contexts and chronological periods and a suitable basis for expansion with additional components.