Hydroclimatic variability of Cyprus with an emphasis on extreme events

In recent years, terms such as climate change, extreme weather events and natural disasters have been increasingly cited. Phenomena such as floods and droughts, combined with continuous population growth and rapid urbanization, adversely affect society and everyday life. The island of Cyprus is no exception, as its geographical location makes it particularly vulnerable and it is considered one of the regions expected to be most affected by the climate crisis in the Mediterranean. The monitoring of such phenomena is of primary importance, as it contributes to the understanding and management of their impacts. Considering the increasing risks they pose to society and the economy, their systematic monitoring is directly linked to the protection of both society and the environment, and constitutes a fundamental prerequisite for the development of effective early warning systems as well as the design of efficient response and adaptation strategies. These phenomena cannot be described in a deterministic manner. Their occurrence, although exhibiting random characteristics, is not entirely random but involves uncertainty and spatiotemporal correlations. This renders their reliable prediction particularly challenging, with stochastic methods representing the most appropriate approach to capturing their behaviour. For this purpose, a thorough examination of hydrometeorological factors is required, as they directly affect the frequency, intensity, and duration of extreme weather events and provide essential information for the understanding of hydrological processes, ultimately supporting the development of reliable forecasting models and the timely adoption of appropriate decisions to mitigate or avoid adverse consequences. The study contributes to the systematic utilisation of long-term hydrometeorological data and to the deepening of the understanding of the spatiotemporal patterns of hydroclimatic variability on the island. This thesis is structured into two main parts. The first investigates hydroclimatic variability across the free territory of Cyprus, with particular emphasis on extreme events. Through statistical analysis of rainfall and runoff parameters, their spatial distribution and temporal behaviour are examined, seasonality is analysed, and spatial patterns as well as vulnerable areas of the island are identified. The second part focuses on the selection of suitable pairs of rainfall and streamflow (discharge) gauging stations, the correlation of precipitation and runoff data for common time periods, and the assessment of the temporal stability of these relationships. Due to the large volume of data, processing was carried out in the Python programming environment. Two independent codes were developed, one for each part, in a universal form, enabling their use by any user with input data of the same format.